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Background: Photoimmunotherapy is a treatment modality that induces targeted cell death by binding a molecular-targeted drug activated by infrared light to the tumor cells and subsequently illuminating the lesion with infrared light. For deep lesions, a needle catheter is used to puncture the tumor, and an illumination fiber (cylindrical diffuser) is inserted into the catheter lumen for internal illumination. However, it can be challenging to place the cylindrical diffusers in an appropriate position as the deep lesions cannot be often confirmed accurately during surgery. Materials and methods: We have developed "SlicerPIT", a planning simulation software for photoimmunotherapy. SlicerPIT allows users to place the cylindrical diffuser with its illumination range on preoperative images in 2D and 3D and export the planning data to external image-guided surgical navigation systems. We performed seven cycles of photoimmunotherapy with SlicerPIT in three patients with recurrent head and neck cancer. Results: Preoperative planning for photoimmunotherapy was conducted using SlicerPIT, which could be imported into the navigation system. During the operation, we punctured the needle catheters along with the treatment plan on the navigation screen. Subsequently, intraoperative CT imaging was performed and overlaid with the preoperative treatment plan to confirm the alignment of the cylindrical diffusers as planned, followed by infrared light illumination. Postoperative imaging showed necrosis and shrinkage of the entire tumor in all cycles. Conclusion: SlicerPIT allows for detailed preoperative treatment planning and accurate puncture. It may be a valuable tool to improve the accuracy of photoimmunotherapy for deep lesions and improve patient outcomes. [ABSTRACT FROM AUTHOR]

Navigation systems are extensively used in everyday life, but the conventional A* algorithm has several limitations in path planning applications within these systems, such as low degrees of freedom in path planning, inadequate consideration of the effects of special regions, and excessive nodes and turns. Addressing these limitations, an enhanced A* algorithm was proposed using regular hexagonal grid mapping. First, the approach to map modeling using hexagonal grids was described. Subsequently, the A* algorithm was refined by optimizing the calculation of movement costs, thus allowing the algorithm to integrate environmental data more effectively and flexibly adjust node costs while ensuring path optimality. A quantitative method was also introduced to assess map complexity and adaptive heuristics that decrease the number of traversed nodes and increase the search speed. Moreover, a turning penalty measure was implemented to minimize unnecessary turns on the planned paths. Simulation results confirmed that the improved A* algorithm exhibits superior performance, which can dynamically adjust movement costs, enhance search efficiency, reduce turns, improve overall path planning quality, and solve critical path planning issues in navigation systems, greatly aiding the development and design of these systems and making them better suited to meet modern navigation requirements. [ABSTRACT FROM AUTHOR]

BACKGROUND. Endoscopic sinus surgery (ESS) has revolutionized the treatment of nasal and paranasal sinus conditions, offering minimally invasive techniques with improved patient outcomes. However, ESS can be challenging, lengthy, and physically demanding. This article presents a comprehensive overview of factors to consider before and during ESS to enhance surgical ease and patient comfort. MATERIAL AND METHODS. The paper is a literature review sustaining a point of view on the factors influencing the outcome of endoscopic sinus surgery. RESULTS. Preoperative considerations encompass a thorough assessment of surgical indications, weighing against medical alternatives as per guidelines. Attention to patient comorbidities, medication management and infection control are paramount. Intraoperatively, collaboration with anesthesiologists is crucial for optimizing patient stability and minimizing complications. Ergonomic considerations, patient positioning and surgical environment optimization contribute to surgeon comfort and procedural efficiency. The surgical procedure entails meticulous preparation of the nasal cavity, preservation of anatomical structures, and adherence to standardized techniques. The sphenoethmoidectomy is described as a sequential five-door procedure, emphasizing anatomical landmarks and meticulous dissection techniques. Hemostasis and the judicious use of powered shavers play pivotal roles in minimizing bleeding and optimizing tissue removal. Navigation systems offer additional support, particularly in complex cases or revision surgeries. CONCLUSION. ESS requires meticulous planning, technical proficiency, and interdisciplinary collaboration to optimize outcomes. Anticipation and adherence to standardized protocols are paramount in navigating the challenges of ESS, ultimately enhancing surgical ease and patient comfort. [ABSTRACT FROM AUTHOR]

The application of robotics has great implications for future food security, sustainable agricultural development, improving resource efficiency, reducing chemical pesticide use, reducing manual labor, and maximizing field output. Aiming at the problems of high labor intensity and labor shortage in the fields of pesticide application, weeding, and field information collection, a multifunctional and electric field management robot platform is designed, which has four switching steering modes (Ackermann steering, four-wheel steering, crab steering, and zero-radius steering), and its wheel-track can be automatically adjusted. Commonly used spraying booms, weeders, crop information collectors, and other devices can be easily installed on the robot platform. A multi-sensor integrated navigation system including a satellite positioning system, an RGB camera, and a multi-line lidar is designed to realize the unmanned driving of the robot platform in a complex field environment. Field tests have shown that the robot can follow the set route, and tests under simulated conditions have indicated that it can also dynamically correct paths based on crop rows by using a visual system. Results from multiple trials showed that the trajectory tracking accuracy meets the requirements of various field management operations. [ABSTRACT FROM AUTHOR]

Background: Electrical storm (ES) is a clinical emergency characterized by multiple malignant ventricular arrhythmias or ICD discharges within 24 h, requiring early rational management. Case presentation: We report a 55-year-old man who underwent aortic valve replacement experienced recurrent ventricular tachycardia/ventricular fibrillation. A temporary permanent pacemaker with the EnSite system was implanted, and significant inhibition of the electrical storm, attributed to the atrial overdrive pacing, ensued. Conclusions: In emergency regarding an electrical storm, the bedside temporary permanent pacemaker implantation with the EnSite system is concluded to be feasible and safe. [ABSTRACT FROM AUTHOR]

Background: Augmented reality (AR), a form of 3D imaging technology, has been preliminarily applied in tumor surgery of the head and spine, both are rigid bodies. However, there is a lack of research evaluating the clinical value of AR in tumor surgery of the brachial plexus, a non-rigid body, where the anatomical position varies with patient posture. Methods: Prior to surgery in 8 patients diagnosed with brachial plexus tumors, conventional MRI scans were performed to obtain conventional 2D MRI images. The MRI data were then differentiated automatically and converted into AR-based 3D models. After point-to-point relocation and registration, the 3D models were projected onto the patient's body using a head-mounted display for navigation. To evaluate the clinical value of AR-based 3D models compared to the conventional 2D MRI images, 2 senior hand surgeons completed questionnaires on the evaluation of anatomical structures (tumor, arteries, veins, nerves, bones, and muscles), ranging from 1 (strongly disagree) to 5 (strongly agree). Results: Surgeons rated AR-based 3D models as superior to conventional MRI images for all anatomical structures, including tumors. Furthermore, AR-based 3D models were preferred for preoperative planning and intraoperative navigation, demonstrating their added value. The mean positional error between the 3D models and intraoperative findings was approximately 1 cm. Conclusions: This study evaluated, for the first time, the clinical value of an AR-based 3D navigation system in preoperative planning and intraoperative navigation for brachial plexus tumor surgery. By providing more direct spatial visualization, compared with conventional 2D MRI images, this 3D navigation system significantly improved the clinical accuracy and safety of tumor surgery in non-rigid bodies. [ABSTRACT FROM AUTHOR]

Background: Intraoperative navigation allows for the creation of a real-time relationship between the anatomy imagined during diagnosis/planning and the site of surgical interest. This procedure takes place by identifying and registering trustworthy anatomical markers on planning images and using a point locator during the operation. The locator is calibrated in the workspace by placing a Dynamic Reference Frame (DRF) sensor. Objective: This study aims to calculate the localization accuracy of an electromagnetic locator of neuro-maxillofacial surgery, moving the standard sensor position to a different position more suitable for maxillofacial surgery. Materials and Methods: The upper dental arch was chosen as an alternative fixed point for the positioning of the sensor. The prototype of a bite support device was designed and generated via 3D printing. CT images of a skull phantom with 10 anatomical landmarks were acquired. The testing procedure consisted of 10 measurements for each position of the sensor: precisely 10 measurements with the sensor placed on the forehead and 10 measurements with the sensor placed on the bite support device. It also evaluated the localization error by comparing the two procedures. Results: The localization error, when the sensor was placed on the bite support device, was lower in the sphere located on the temporal bone. It was the same in the spheres located on the maxillary bone. The test analysis of the data of the new device showed that it is reliable; the tests are reproducible and can be considered as accurate as the traditional ones. In addition, the sensor mounted on this device has proven to be slightly superior in terms of accuracy and accuracy in areas such as the middle third of the face and jaw. Discussion and Conclusion: The realization of the bite support device allowed the sensor to change position concerning its natural site. This procedure allows us to explore structures, such as the frontal site, which were initially difficult to approach with neuronavigation and improves the approach to midface structures, already studied with neuronavigation. The new calibration, with the position of the sensor on the support device in the same reference points sphere, highlighted the reduction in the location error. We can say that the support proposed in this study lays the foundations for a new navigation approach for patients in maxillofacial surgery, by changing the position of the sensor. It has strong points in improving the localization error for some reference points without determining disadvantages both in the calibration and in the surgical impediment. [ABSTRACT FROM AUTHOR]

Many teams participating in robotic competitions achieve localization using a 2D map plotted using adaptive Monte Carlo localization, a robot operating system (ROS) open-source software program. However, outdoor environments often include nonlevel terrain such as slopes. In the indoor environment of multilevel structures, the data representing different levels overlap on the map. These factors can lead to localization failures. To resolve this problem, we develop a software by combining HDL localization, which is an ROS open-source software, with our own program, and use it to achieve localization based on a 3D map. Furthermore, the authors observe the erroneous recognition of a slope as a forward obstacle during a competition event. To resolve this, we propose a method to correct erroneous recognition of obstacles using a 2D laser range finder and 3D map and confirm its validity in an experiment carried out on a slope on a university campus. [ABSTRACT FROM AUTHOR]

Meteorological conditions significantly affect air traffic safety and can also affect a pre-planned flight plan. Difficult meteorological conditions are particularly hazardous during take-off and landing procedures. Still, they can also cause disruptions to air traffic by causing, for example, delays to air traffic or diversion of aircraft to other airports. From the airlines' point of view, such situations are not beneficial if flights are diverted to other airports due to reduced visibility at the airport caused by fog and haze. For flight operations, a popular navigation system with a precision approach is the ILS, which has several categories enabling an approach even in adverse meteorological conditions. However, not every airport has a high-category ILS, and setting up such navigation equipment is lengthy and costly. The main objective of this article is to analyze the impact of meteorological conditions, particularly visibility, on the possibility of performing flight procedures with different ILS categories. The study was designed to quantify the limitations associated with meteorological conditions with specific ILS equipment at a given airport. The research questions for this study include the following: What were the meteorological conditions in terms of visibility? What impact did the visibility parameter have on the performance of landing operations at the airport under study? Can an indication of the probability of stopping landing operations be important in recommendations for scheduling airline flights to avoid delays? Three airports were selected for the analysis: Warsaw Chopin Airport, Warsaw Modlin Mazowiecki Airport, and Krakow John Paul II Airport. The analysis was based on approximately 52,000 METAR dispatches in 2019 and 2022. The research indicated during which periods landing procedures were most frequently halted and calculated such a change with a different category of ILS. For the Kraków Airport, the probability of stopping landing procedures in any month was calculated, along with recommendations for flight schedule planning for this airport. The research results can be used to better plan airline flight schedules, avoiding hours with a high probability of reduced visibility, which may result in rerouting flights to another airport. Long-term low clouds and reduced visibility affect the safety of operations but also cause delays. [ABSTRACT FROM AUTHOR]

Experimental verification of numerical models is a key aspect in all scientific and technological disciplines, yet space systems can be particularly hard to test on ground: in fact, a terrestrial mock-up replicating the orbital dynamics should be in a microgravity environment. One of the most common approaches to (at least partially) realize this condition, consists in free-floating systems, in which the friction between an experimental platform and the working surface is almost completely removed. The vertical axis is still subject to gravity, and only 3° of freedom (two horizontal translations and one rotation about the vertical axis) are available to replicate the orbital behavior. Our research group had been developing since 2012 a free-floating platform named PINOCCHIO (Platform Integrating Navigation and Orbital Control Capabilities Hosting Intelligent Onboard). The need to investigate with higher accuracy the attitude control problem for flexible satellites called for the design, realization and characterization of a new platform with enhanced performance. This paper describes the main components of the system, including the pressure air system, the navigation and communication system, the Guidance, Navigation and Control (GNC) architecture and relevant hardware. The attention is specifically on the characterization of the subsystems' performance. The physical (mass, moment of inertia), control (thrusters' torque and force) and Inertial Measurement Unit (IMU) characteristics are experimentally measured with the associated uncertainty level. The accuracy of the external metrology system in static and dynamic conditions is also characterized, obtaining a 100 μm-level resolution for external measurement of rigid and elastic displacements; this information is fundamental for performing tests of fine pointing control algorithms for flexible and agile satellites. The proposed characterization methodology and associated results could be of interest for university and industry laboratories intended to develop new free-floating platforms. • The characterization procedure of a free-floating platforms is reported. • A stepwise procedure requires to first characterize the supplied thrust accurately. • Inertia properties can be next determined. • Accurate optical navigation is presented and characterized. • Performance of the platform for flexible satellite attitude test is introduced. [ABSTRACT FROM AUTHOR]

With the development of mechatronics robot intelligence and autonomy, automatic obstacle avoidance and path planning has become the core of the current robot navigation system research. This research aims to solve the problems of complex path planning and poor parameter strain in ultrasonic array navigation systems. Firstly, the research status of the mobile robot is introduced, and a new embedded navigation system based on ultrasonic array technology is designed. Then, the fuzzy control algorithm is introduced, and a new Positive/Negative (P/N) local path planning algorithm based on fuzzy control is proposed. The normal rule is used to make the robot move toward the target point, in which the robot avoids obstacles through negative rules. The complexity of the fuzzy system is reduced through binary negative rules. Then, the precise output is obtained through the path decision formula to realize the local path planning system of the mechatronic robot. Finally, the simulation results verify the effectiveness of the improved algorithm. Based on the joint simulation experiment platform of Simulink and Robot Operating System (ROS), the excellent performance of the proposed embedded navigation system has been verified. The new P/N local path planning algorithm of fuzzy control can make the running track more accurate and smoother by optimizing the path. The new embedded navigation system can provide theoretical analysis and practical reference for developing an electromechanical robot navigation system. [ABSTRACT FROM AUTHOR]

Anterior decompression and fusion (ADF) using the floating method for cervical ossification of the posterior longitudinal ligament (OPLL) is an ideal surgical technique, but it has a specific risk of insufficient decompression caused by the impingement of residual ossification. Augmented reality (AR) support is a novel technology that enables the superimposition of images onto the view of a surgical field. AR technology was applied to ADF for cervical OPLL to facilitate intraoperative anatomical orientation and OPLL identification. In total, 14 patients with cervical OPLL underwent ADF with microscopic AR support. The outline of the OPLL and the bilateral vertebral arteries was marked after intraoperative CT, and the reconstructed 3D image data were transferred and linked to the microscope. The AR microscopic view enabled us to visualize the ossification outline, which could not be seen directly in the surgical field, and allowed sufficient decompression of the ossification. Neurological disturbances were improved in all patients. No cases of serious complications, such as major intraoperative bleeding or reoperation due to the postoperative impingement of the floating OPLL, were registered. To our knowledge, this is the first report of the introduction of microscopic AR into ADF using the floating method for cervical OPLL with favorable clinical results. [ABSTRACT FROM AUTHOR]

Simple Summary: In endoscopic transsphenoidal skull base surgery, it is often difficult to accurately determine the location of a tumor and its surroundings on imaging because the lesion remarkably displaces the geography of normal anatomic structures. We aimed to create a novel augmented reality (AR) navigation system that could compensate for this displacement effect. We created a precise three-dimensional computer graphic (3DCG) model that we superimposed on a visual image of the actual surgical field and displayed on a video monitor during endoscopic transsphenoidal surgery. Surgeons evaluated its efficacy using a five-point scale in 15 consecutive patients with sellar and parasellar tumors. The average score overall was 4.7 (95% confidence interval: 4.58–4.82), and the AR navigation system was considered as useful as or more useful than conventional navigation in certain patients. This system has the advantage of facilitating an immediate 3D understanding of the lesion and surrounding structures. In endoscopic transsphenoidal skull base surgery, knowledge of tumor location on imaging and the anatomic structures is required simultaneously. However, it is often difficult to accurately reconstruct the endoscopic vision of the surgical field from the pre-surgical radiographic images because the lesion remarkably displaces the geography of normal anatomic structures. We created a precise three-dimensional computer graphic model from preoperative radiographic data that was then superimposed on a visual image of the actual surgical field and displayed on a video monitor during endoscopic transsphenoidal surgery. We evaluated the efficacy of this augmented reality (AR) navigation system in 15 consecutive patients with sellar and parasellar tumors. The average score overall was 4.7 [95% confidence interval: 4.58–4.82], which indicates that the AR navigation system was as useful as or more useful than conventional navigation in certain patients. In two patients, AR navigation was assessed as less useful than conventional navigation because perception of the depth of the lesion was more difficult. The developed system was more useful than conventional navigation for facilitating an immediate three-dimensional understanding of the lesion and surrounding structures. [ABSTRACT FROM AUTHOR]

A navigation system is critical for the operation of autonomous vehicles. Various sensors must be used to build navigation systems. To fuse multiple sensors, a highly advanced filter algorithm is required. Navigation systems have difficulties in signal-degraded scenarios, where the navigation solution can be degraded by errors such as multipath and obscured signals. This paper proposes a navigation system using a technique to reject the outliers measured by sensors. The navigation system was designed to include sensor modeling, navigation filters, and outlier rejection. The sensors used in the navigation system are the accelerometer, gyroscope, magnetometer, and global positioning system. Before the experiment, a navigation simulation was performed to evaluate the results and validate the proposed navigation algorithm. The results of the experiment verified that the navigation system, including outlier rejection, had less positional error than that of the general navigation system. [ABSTRACT FROM AUTHOR]

Path planning plays a vital role in a mobile robot navigation system. It essentially generates the shortest traversable path between two given points. There are many path planning algorithms that have been proposed by researchers all over the world; however, there is very little work focussing on path planning for a service environment. The general assumption is that either the environment is fully known or unknown. Both cases would not be suitable for a service environment. A fully known environment will restrict further expansion in terms of the number of navigation points and an unknown environment would give an inefficient path. Unlike other environments, service environments have certain factors to be considered, like user-friendliness, repeatability, scalability, and portability, which are very essential for a service robot. In this paper, a simple, efficient, robust, and environment-independent path planning algorithm for an indoor mobile service robot is presented. Initially, the robot is trained to navigate to all the possible destinations sequentially with a minimal user interface, which will ensure that the robot knows partial paths in the environment. With the trained data, the path planning algorithm maps all the logical paths between all the destinations, which helps in autonomous navigation. The algorithm is implemented and tested using a 2D simulator Player/Stage. The proposed system is tested with two different service environment layouts and proved to have features like scalability, trainability, accuracy, and repeatability. The algorithm is compared with various classical path planning algorithms and the results show that the proposed path planning algorithm is on par with the other algorithms in terms of accuracy and efficient path generation. [ABSTRACT FROM AUTHOR]

The biopsy procedure is intended to obtain an adequate specimen volume from the targeted area while ensuring minimal damage to the normal brain. We performed navigation-guided endoscopic biopsy using a small-diameter cylinder to reduce the invasiveness of the biopsy procedure and ensure a sufficient amount of tissue is collected. We examined whether it is possible to reduce brain tissue injury by using a small-diameter cylinder and improve safety and effectiveness by using an endoscope to directly observe the lesion and achieve hemostasis. Patients who underwent endoscopic biopsy surgery using a 6-mm-diameter cylinder for intraparenchymal lesions were enrolled in this study. Postoperative hematoma formation and the extent of trajectory scarring were assessed. Fifty-two procedures performed on 51 patients were analyzed in this study. Postoperative neurological deterioration was not observed in any patient. A pathological diagnosis was made for all patients. Postoperative computed tomography revealed no hematoma after 49 procedures and a small hematoma after 3 procedures, and no patients required additional treatment. A postoperative trajectory scar less than 5 mm in diameter was observed after 30 procedures, a scar of 5–10 mm was observed after 19 procedures, a scar larger than 10 mm was observed after 3 procedures at 1 week after surgery, and 40, 6 and 0 scars were observed at 3 months after surgery. Endoscopic biopsy using a small-diameter cylinder is a possible alternative biopsy technique for intraparenchymal lesions. This surgical technique is useful, especially in patients at risk of hemorrhagic complications. [ABSTRACT FROM AUTHOR]

Objective: Cerebral cavernous malformations (CMs) presenting with focal neurological symptoms or mass effects require surgical removal. In recent years, cylindrical retractors have been widely utilized for the removal of deep-seated lesions during both microscopic and endoscopic surgery. In the present study, we evaluated the efficacy and safety of endoscopic transcylinder removal of CMs using a novel wet-field technique. Methods: We included 13 patients with supratentorial CMs who had undergone endoscopic transcylinder surgery between April 2013 and March 2022. One patient experienced recurrence of the CM and underwent a second endoscopic transcylinder surgery. Therefore, we retrospectively evaluated 14 procedures. The surgical field was continuously irrigated with artificial cerebrospinal fluid to maintain expansion and visualization of the tumor bed. We termed this method as the "wet-field technique." Patient characteristics, symptoms, and pre- and postoperative magnetic resonance imaging results were obtained from medical records. Results: The average maximum CM diameter was 35.3 mm (range: 10–65 mm). Cylinder diameters were 6 mm in eight procedures, 10 mm in four procedures, and 17 mm in one procedure. Wet-field technique was applied in all cases. The endoscope provided a bright field of view even under water. Continuous water irrigation made it easier to observe the entire tumor bed which naturally expanded by water pressure. Gross total resection was achieved in 13 procedures, while subtotal resection was achieved in one procedure. No surgical complications were observed. Conclusions: The endoscopic transcylinder removal using wet-field technique is safe and effective for the removal of symptomatic intracranial supratentorial CMs. [ABSTRACT FROM AUTHOR]

Public transport maps are typically designed in a way to support route finding tasks for passengers, while they also provide an overview about stations, metro lines, and city-specific attractions. Most of those maps are designed as a static representation, maybe placed in a metro station or printed in a travel guide. In this paper, we describe a dynamic, interactive public transport map visualization enhanced by additional views for the dynamic passenger data on different levels of temporal granularity. Moreover, we also allow extra statistical information in form of density plots, calendar-based visualizations, and line graphs. All this information is linked to the contextual metro map to give a viewer insights into the relations between time points and typical routes taken by the passengers. We also integrated a graph-based view on user-selected routes, a way to interactively compare those routes, an attribute- and property-driven automatic computation of specific routes for one map as well as for all available maps in our repertoire, and finally, also the most important sights in each city are included as extra information to include in a user-selected route. We illustrate the usefulness of our interactive visualization and map navigation system by applying it to the railway system of Hamburg in Germany while also taking into account the extra passenger data. As another indication for the usefulness of the interactively enhanced metro maps we conducted a controlled user experiment with 20 participants. [ABSTRACT FROM AUTHOR]

• Proposed an autonomous navigation scheme for orchard spraying robots based on multi-sensor devices and the 3D LiDAR SLAM technology. • Improved the hdl_graph_slam algorithm, where point cloud registration combined NDT and ICP. • Designed a point cloud map transformation algorithm to convert the 3D point cloud map of the orchard into a 2D grid map containing key feature information of the orchard. • Designed a multi-threaded cooperative obstacle avoidance method to reduce the robot's local obstacle avoidance blind spots. Autonomous navigation of orchard spraying robots can effectively improve operational efficiency and reduce workload. The conventional robot navigation solutions based on the Global Navigation Satellite System (GNSS) are susceptible to signal loss in orchards due to interference from the canopy of fruit trees. In this paper, an autonomous navigation scheme for orchard spraying robots based on multi-sensor devices and the three-dimensional (3D) LiDAR Simultaneous Localization and Mapping (SLAM) technology. The initial step of the scheme involved the construction of a 3D point cloud map of the orchard using the 3D LiDAR SLAM algorithm. Subsequently, a designed point cloud map transformation algorithm was used to convert the 3D point cloud map of the orchard into a two-dimensional (2D) grid map containing key feature information of the orchard. To enhance the mapping accuracy of the orchard point cloud, a point cloud registration algorithm combining Iterative Closet Point (ICP) and Normal Distributions Transform (NDT) was proposed. This algorithm initially utilized the NDT algorithm for coarse point cloud registration to obtain transformation parameters. Then, the ICP algorithm was applied in conjunction with the obtained parameters for fine registration. Regarding obstacle avoidance, a cooperative obstacle avoidance algorithm based on the Robot Operating System (ROS) multithreaded communication mechanism was introduced. Experimental trials conducted in a standardized spindle-shaped peach orchard validated the successful completion of the SLAM mapping trajectory, which was achieved through the utilization of the proposed NDT_ICP point cloud registration algorithm. The average absolute pose error between the mapped trajectory and the reference trajectory was 1.173 m, with a standard deviation of 0.498 m. The robot's positioning and navigation errors increased with higher speeds, with the largest positioning deviation observed at 1.2 m/s speed, with a maximum lateral positioning error of 7.04 cm. The robot's average lateral navigation error did not exceed 16 cm, and the average heading deviation was less than 8° at different speeds of 0.4, 0.8 and 1.2 m/s. Both the positioning and navigation accuracies of the robot were sufficient to meet the autonomous operational requirements of orchard spraying robots. [ABSTRACT FROM AUTHOR]

New applications are continuously appearing with drones as protagonists, but all of them share an essential critical maneuver—landing. New application requirements have led the study of novel landing strategies, in which vision systems have played and continue to play a key role. Generally, the new applications use the control and navigation systems embedded in the aircraft. However, the internal dynamics of these systems, initially focused on other tasks such as the smoothing trajectories between different waypoints, can trigger undesired behaviors. In this paper, we propose a landing system based on monocular vision and navigation information to estimate the helipad global position. In addition, the global estimation system includes a position error correction module by cylinder space transformation and a filtering system with a sliding window. To conclude, the landing system is evaluated with three quality metrics, showing how the proposed correction system together with stationary filtering improves the raw landing system. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the in vivo knee laxity in the presence of a partial medial meniscectomy before and after a single-bundle ACL reconstruction with a lateral plasty (SBLP) and to compare it with the knee laxity after a single-bundle ACL reconstruction (SB). Methods: One-hundred and one patients with ACL tear were enrolled in the study and grouped according to the surgical technique and the meniscus treatment: regarding the SBLP technique (n = 55), 31 patients underwent isolated ACL reconstruction ("SBLP Isolated ACL Group"), while 24 patients underwent combined ACL reconstruction and partial medial meniscectomy ("SBLP ACL + MM Group"); regarding the SB technique (n = 46), 33 patients underwent isolated ACL reconstruction ("SB Isolated ACL Group"), while 13 patients underwent combined ACL reconstruction and partial medial meniscectomy ("SB ACL + MM Group"). Anterior–posterior clinical laxity at 30° (AP30) and 90° (AP90) of knee flexion was quantified before and after surgery through a surgical navigation system dedicated to kinematic assessment. Results: In the ACL-deficient status, the antero-posterior laxity was significantly higher in the presence of a combined MM in both the AP30 and the AP90, with no differences between the two surgical techniques. After the ACL reconstruction, both AP30 and AP90 translations decreased significantly (p < 0.0001) compared to the ACL-deficient status. No differences were found for AP30 and AP90 between SBLP Isolated ACL and SBLP + MM groups, while a significantly higher AP90 translation was found for the SB + MM group compared to the SB Isolated ACL group. Moreover, the AP90 translation in the SB ACL + MM group was significantly higher than the one of the other three groups, i.e., SBLP ACL + MM, SB, and SBLP Isolated ACL group. Conclusion: The ACL reconstruction with lateral plasty reduced the AP knee laxity caused by the medial meniscectomy in the context of an ACL surgery. Level of evidence: Level II. [ABSTRACT FROM AUTHOR]

The world for normal human being is far different than visually impaired, due to either lack of vision or no vision. The difficulties in their daily routines can be minimized with help of technological support which is usually aids that can be used for travelling. Computer vision a field of artificial intelligence provides the assistance for helping impaired. The assembly of the device is made as handy as of user is using mobile and the architecture of YOLO (You Only Look Once) is used for accurate object detection. The feature detection of YOLO is more appropriate in real time. The object or the obstacle from which user can collide or the pedestrian localization is indicated to user with help of speaker which make system valuable. The compact size, Raspberry Pi 4 B 8 GB is used or processing, which has proved accuracy of 98% in real time scene. The world for normal human being is far different than visually impaired, due to either lack of vision or no vision. The difficulties in their daily routines can be minimized with help of technological support which is usually aids that can be used for travelling. Computer vision a field of artificial intelligence provides the assistance for helping impaired. The assembly of the device is made as handy as of user is using mobile and the architecture of YOLO (You Only Look Once) is used for accurate object detection. The feature detection of YOLO is more appropriate in real time. The object or the obstacle from which user can collide or the pedestrian localization is indicated to user with help of speaker which make system valuable. The compact size, Raspberry Pi 4 B 8 GB is used or processing, which has proved accuracy of 98% in real time scene. [ABSTRACT FROM AUTHOR]

Background: The choice of mobile bearing (MB) thickness is essential for obtaining successful results after mobile-bearing Oxford unicompartmental knee arthroplasty (UKA). This study aimed to investigate the effects of a 1-mm difference in bearing thickness on intraoperative MB movement and intraoperative knee kinematics in Oxford UKAs.Methods: We prospectively investigated the effects of a 1-mm difference in bearing thickness on intraoperative MB movement and knee kinematics in 25 patients who underwent Oxford UKAs when surgeons didn't know which bearing thickness to choose with 1-mm difference. A trial tibial component that was scaled every 2 mm was used to measure the intraoperative MB movement, and the tibial internal rotation relative to the femur and the knee varus angle was simultaneously evaluated using the navigation system as the knee kinematics. We separately evaluated sets of two MB thicknesses with 1-mm differences, and we compared the intraoperative parameters at maximum extension; 30º, 45º, 60º, and 90º flexion; and maximum flexion between the thicker MB (thick group) and the thinner MB (thin group).Results: The MB in the thin group was located significantly posteriorly at 90º flexion compared with that in the thick group; however, there were no differences at the other flexion angles. There was significantly less tibial internal rotation in the thin group at 90º flexion than that in the thick group; however, there were no differences at the other flexion angles. The knee varus angles in the thick group were significantly smaller than those in the thin group by approximately one degree at all angles other than at 30º and 45º flexion.Conclusion: The thicker MB could bring the less posterior MB movement and the more tibial internal rotation at 90º flexion, additionally the valgus correction angle in the thicker MB should be paid attention. These results could help surgeons to decide the thickness of MBs when they wonder the thickness of MB. [ABSTRACT FROM AUTHOR]

The requirement to estimate the six degree-of-freedom pose of a moving platform frequently arises in automation applications. It is common to estimate platform pose by the fusion of global navigation satellite systems (GNSS) measurements and translational acceleration and rotational rate measurements from an inertial measurement unit (IMU). This paper considers a specific situation where two GNSS receivers and one IMU are used and gives the full formulation of a Kalman filter-based estimator to do this. A limitation in using this sensor set is the difficulty of obtaining accurate estimates of the degree of freedom corresponding to rotation about the line passing through the two GNSS receiver antenna centres. The GNSS-aided IMU formulation is extended to incorporate LiDAR measurements in both known and unknown environments to stabilise this degree of freedom. The performance of the pose estimator is established by comparing expected LiDAR range measurements with actual range measurements. Distributions of the terrain point-to-model error are shown to improve from 0.27 m mean error to 0.06 m when the GNSS-aided IMU estimator is augmented with LiDAR measurements. This precision is marginally degraded to 0.14 m when the pose estimator is operated in an a prior unknown environment. [ABSTRACT FROM AUTHOR]

Background: This study aimed to determine the predictors of tight extension gap (EG) compared with the flexion gap (FG) during navigational posterior stabilized-type total knee arthroplasty using the pre-cut technique.Methods: Nineteen patients with tight EG (defined as FG-EG ≥2 mm after pre-cut; group T) and 84 patients with an approximately equal gap (defined as FG-EG = 0-1 mm after pre-cut; group E) were enrolled. Medial tibial slope angle, hip knee ankle angle, flexion contracture angle, and active maximum flexion angle were compared between the two groups.Results: The multivariate logistic regression model indicated that the probability of tight EG increased with flexion contracture angle (odds ratio, 1.13; 95% confidence interval 1.05-1.20; P ≤ 0.001). According to the receiver operating characteristic analysis, the flexion contracture angle cut-off value associated with tight EG was 15.0° (sensitivity, 85%; specificity, 78%).Conclusion: This study demonstrated that a large flexion contracture angle (cut-off 15.0°) was associated with tight EG after pre-cut osteotomy during posterior stabilized-type total knee arthroplasty. Awareness of this risk factor may help improve preoperative predictability of tight EGs and preparedness for additional procedures, such as soft tissue release or capsulotomy, to correct them.Level Of Evidence: Level III. [ABSTRACT FROM AUTHOR]

• Image registration and EM tracking were integrated in a system for HDR brachytherapy. • EM enabled use of partially visible catheters within image-validated implants. • MRI-TRUS registration permits GTV projection over real-time TRUS for tumor-targeting. • Elastic registration performs slightly better than rigid registration, but errors remain. • Alignment of the urethral angle before deformation improved registration accuracy. Advances in high-dose-rate brachytherapy to treat prostate cancer hinge on improved accuracy in navigation and targeting while optimizing a streamlined workflow. Multimodal image registration and electromagnetic (EM) tracking are two technologies integrated into a prototype system in the early phase of clinical evaluation. We aim to report on the system's accuracy and workflow performance in support of tumor-targeted procedures. In a prospective study, we evaluated the system in 43 consecutive procedures after clinical deployment. We measured workflow efficiency and EM catheter reconstruction accuracy. We also evaluated the system's MRI-TRUS registration accuracy with/without deformation, and with/without y-axis rotation for urethral alignment at initialization. The cohort included 32 focal brachytherapy and 11 integrated boost whole-gland implants. Mean procedure time excluding dose delivery was 38 min (range: 21–83) for focal, and 56 min (range: 38–89) for whole-gland implants; stable over time. EM catheter reconstructions achieved a mean difference between computed and measured free-length of 0.8 mm (SD 0.8, no corrections performed), and mean axial manual corrections 1.3 mm (SD 0.7). EM also enabled the clinical use of a non or partially visible catheter in 21% of procedures. Registration accuracy improved with y-axis rotation for urethral alignment at initialization and with the elastic registration (mTRE 3.42 mm, SD 1.49). The system supported tumor-targeting and was implemented with no demonstrable learning curve. EM reconstruction errors were small, correctable, and improved with calibration and control of external distortion sources; increasing confidence in the use of partially visible catheters. Image registration errors remained despite rotational alignment and deformation, and should be carefully considered. [ABSTRACT FROM AUTHOR]

Path planning plays a vital role in a mobile robot navigation system. It essentially generates the shortest traversable path between two given points. There are many path planning algorithms that have been proposed by researchers all over the world; however, there is very little work focussing on path planning for a service environment. The general assumption is that either the environment is fully known or unknown. Both cases would not be suitable for a service environment. A fully known environment will restrict further expansion in terms of the number of navigation points and an unknown environment would give an inefficient path. Unlike other environments, service environments have certain factors to be considered, like user-friendliness, repeatability, scalability, and portability, which are very essential for a service robot. In this paper, a simple, efficient, robust, and environment-independent path planning algorithm for an indoor mobile service robot is presented. Initially, the robot is trained to navigate to all the possible destinations sequentially with a minimal user interface, which will ensure that the robot knows partial paths in the environment. With the trained data, the path planning algorithm maps all the logical paths between all the destinations, which helps in autonomous navigation. The algorithm is implemented and tested using a 2D simulator Player/Stage. The proposed system is tested with two different service environment layouts and proved to have features like scalability, trainability, accuracy, and repeatability. The algorithm is compared with various classical path planning algorithms and the results show that the proposed path planning algorithm is on par with the other algorithms in terms of accuracy and efficient path generation. [ABSTRACT FROM AUTHOR]

To solve the problems of autonomous underwater vehicle ( AUV) with high test cost, requiring ideal simulation environment for the application of underwater robots and robot verification and difficult modeling of simulation environment, the MOOS software system was used to perform navigation, communication and three-dimensional simulation of the AUV navigation system. The communication methods, the software architecture, the data collection methods and the sensor data types of the MOOS software system were configured and simulated. Based on the perspectives of mechanism, the data subscription and publication and the data analysis and processing, the MOOS software system was analyzed and verified. The results show that the MOOS system can generate relevant environmental sensor data according to the preset trajectory of AUV, which can effectively realize multi-source information fusion and navigation pose calculation. [ABSTRACT FROM AUTHOR]

Objective: To describe the surgical technique of navigation-guided nasal osteotomies and assess feasibility of this technique for treating complex nasal bone deformities in reconstructive rhinoplasty. Methods: A retrospective chart review was performed in order to identify patients who underwent computer-aided rhinoplasty from August 2014 to February 2017. Inclusion criteria were nasal bone deformities on computed-tomography (CT) that correlated with specific nasal complaints. All patients underwent computer-aided rhinoplasty with navigation-guided nasal osteotomies using a standard navigation system. Osteotomies were performed using real-time visualization on the navigation screen. Additional soft tissue procedures were performed as needed. Medical records were reviewed for presenting symptoms, radiologic and operative findings, and postoperative course. Cosmetic outcomes were subjectively based on patients' standard 6-view photo-documentation from pre- and post-operative timepoints. Results: Twenty-one patients were included in the study; 8 were revision cases and 3 had mild-to-moderate hemifacial microsomia. Fifteen were completely closed procedures. No cases were opened because of inadequate visualization or difficulty accessing bony pathology. Mean (range) follow up was 98.6 (6-559) days. There were no intra-operative complications, unplanned admissions or re-admissions, or iatrogenic cosmetic complications (ie, "inverted V" or "saddle nose" deformities). Two patients required revision. One was after suffering nasal trauma within 4 weeks of initial rhinoplasty. The second underwent further correction of a deformity that required a costochondral graft. Both experienced good final results. Conclusions: Computer-aided rhinoplasty is safe and feasible for treating complex nasal deformities using standard navigation systems. [ABSTRACT FROM AUTHOR]

Purpose: The use of Electromagnetic navigation bronchoscopy (ENB) for the diagnosis of pulmonary peripheral lesions is still debated due to its variable diagnostic yield; a new 4D ENB system, acquiring inspiratory and expiratory computed tomography (CT) scans, overcomes respiratory motion and uses tracked sampling instruments, reaching higher diagnostic yields. We aimed at evaluating diagnostic yield and accuracy of a 4D ENB system in sampling pulmonary lesions and at describing their influencing factors. Methods: We conducted a three-year retrospective observational study including all patients with pulmonary lesions who underwent 4D ENB with diagnostic purposes; all the factors potentially influencing diagnosis were recorded. Results: 103 ENB procedures were included; diagnostic yield and accuracy were, respectively, 55.3% and 66.3%. We reported a navigation success rate of 80.6% and a diagnosis with ENB was achieved in 68.3% of cases; sensitivity for malignancy was 61.8%. The majority of lesions had a bronchus sign on CT, but only the size of lesions influenced ENB diagnosis (p < 0.05). Transbronchial needle aspiration biopsy was the most used tool (93.2% of times) with the higher diagnostic rate (70.2%). We reported only one case of pneumothorax. Conclusion: The diagnostic performance of a 4D ENB system is lower than other previous navigation systems used in research settings. Several factors still influence the reachability of the lesion and therefore diagnostic yield. Patient selection, as well as the multimodality approach of the lesion, is strongly recommended to obtain higher diagnostic yield and accuracy, with a low rate of complications. [ABSTRACT FROM AUTHOR]

Background: The accuracies of various navigation systems in total hip arthroplasty (THA) have been described; however, the accuracy of cup orientation with an accelerometer-based navigation system has not been reported. The purpose of this study was to compare the accuracies of computed tomography (CT)- and accelerometer-based navigation systems for cup orientation in THA. Methods: In this prospective study, 30 patients who underwent cementless THA via anterolateral approach in the lateral decubitus position were analysed. A CT-based navigation system (30 hips) and an accelerometer-based navigation system (30 hips) were used simultaneously. The accuracy of cup orientation (absolute difference between intraoperative vs. postoperative measurements) was compared between the navigation systems using postoperative CT. Results: The accuracy of cup inclination was 3.2 ± 2.4° in the CT-based navigation group and 4.1 ± 3.7° in the accelerometer-based navigation group (p = 0.3035). The accuracy of cup anteversion was 3.0° ± 2.5° in the CT-based navigation group and 6.8° ± 4.8° in the accelerometer-based navigation group. Cup anteversion was significantly more accurate with the CT-based navigation system than with accelerometer-based navigation (p = 0.0009). Multiple regression analysis demonstrated that the malposition in cup anteversion was positively correlated with the change in pelvic tilt and loosening of the reference antenna. Conclusions: Although, these results are only true for this specific accelerometer system, cup positioning was significantly more accurate with the CT-based navigation system than an accelerometer-based navigation in the lateral decubitus position. This is because of considerable discrepancies in the sagittal pelvic tilt, resulting in variability in cup anteversion angle with the use of an accelerometer-based navigation system. [ABSTRACT FROM AUTHOR]

The pedestrian navigation system using inertial and magnetic sensors can determine the pedestrian’s attitude and position. However, magnetic field measurement is affected by external magnetic interference, which leads to heading error. Therefore, it is of great importance to suppress magnetic interference. The magnetic threshold method is often used to detect magnetic interference. However, this method fails under the weak magnetic interference environment because the magnetic field intensity measurement is approximately equal to that of the geomagnetic intensity. A generalized likelihood ratio test (GLRT) is proposed in this study. A likelihood ratio function is constructed to maximize the phase probability of magnetic interference so that the inequality relation for detection can be determined. In addition, zero velocity update (ZUPT) algorithm including extended Kalman filter (EKF) or extended Kalman particle filter (EKPF) can suppress accumulated errors, but the heading deviation cannot be accurately estimated. Therefore, an improved EKPF is designed to compensate heading observation by adding adaptive parameters. In order to verify the advantages of the proposed method, the pedestrian navigation system is established and experiments are performed. The false detection rate of the proposed GLRT method decreased by 14.36% compared with the conventional method. Furthermore, the positioning error is reduced by improved EKPF, compared with EKF and EKPF. Therefore, the methods proposed in this study improve the heading and positioning accuracy under a magnetic interference environment. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to describe the sagittal geometry of the trochlear groove in patients who underwent primary TKA, based on intraoperative data acquired with a navigation system.Methods: Intraoperative navigation data were collected from 110 patients. All operations were guided by a non-image-based navigation system (BLU-IGS, Orthokey Italia Srl). The trochlear groove has been described on the three anatomical planes; in particular, on the sagittal plane the hypothesis has been verified that the acquired points are referable to a circle. Using the data collected during intraoperative navigation, possible correlation between the radius of the trochlear groove and other femur dimension (length, AP dimension) was analyzed; the orientation of the trochlear sulcus with respect to the mechanical axis and the posterior condyle axis was analyzed too, searching for possible correlation between groove alignment (frontal and axial) or groove radius and the hip-knee-ankle (HKA).Results: The average radius of curvature of the femoral trochlea was 25.5 ± 5.6 mm; the difference was not statistically significant between the men and women (n.s. p value). No correlation was found between the trochlear groove radius and the femur length (r = - 0.02) or the HKA-phenotypes (r = 0.03) and between the groove alignment and HKA-phenotypes. On axial plane, the trochlear groove was 3.2° ± 4.3° externally rotated, with respect to the posterior condylar axis; on frontal plane, the trochlear groove was 3.9° ± 5.3° externally rotated, with respect to the mechanical axis. In both cases, no statistically significant differences were found between male and female and between left and right limb (p > 0.05).Conclusion: The present study shows that the sagittal plane geometry of the femoral trochlea in patients affected by osteoarthritis could be described accurately as a circle. The acquisition of the trochlear morphology intraoperatively can lead to more anatomically shape definition, to investigate deeper its radius of curvature and geometry. Trochlear shape could be used as landmarks for femoral component positioning, thus customizing the implant design, optimize the outcomes and improving anterior knee pain after TKA.Level Of Evidence: IV. [ABSTRACT FROM AUTHOR]

Due to the last increase in data and information technology, the need to use robots in many life areas is increased. There is a great diversity in this field, depending on the type of task required, as the robot enters the parcels of air, land, and water. In this paper, a robot's mission designed to move things is concentrated, relying on line-tracing technology that makes it easy to track its path safely, the RFID is distributed in its approach. When the robot reads the RFID tag, it stops until it raises the load from above, the robot continues its path toward the target. When an obstacle obstructs the robot path, the robot deviates and returns after a while to its previous approach. All this technology is implemented using a new algorithm which is programmed using the visual basic program. The robot designed to transfer the stored material is used according to a site known as an identifier that is identified by the RFID value, where the robot is programmed through a microcontroller and a unique store program that determines the current location and the desired location, then is given the task for the robot to do it as required. The robot is controlled using an ATmega controller to control other parts connected to the electronic circuit, the particular infrared sensor, and ultrasound to avoid potential obstacles within the robot's path to reach the target safely. In addition to this, the robot is made up of an RFID sensor to give unique to each desired target site. Through the console, it is possible to know the link indicated by the target. The H-bridge is also used to obtain a particular command and guide the robot as needed to move freely in all directions and a DC motor which is unique for moving wheels at the desired speed, and Bluetooth for programmable and secure wireless transmission and reception with all these parts through a unique program that also uses application inventory. The robot has proven to be a great success in performing the required task through several tests that have been practically performed. [ABSTRACT FROM AUTHOR]

In recent few years, the widespread applications of indoor navigation have compelled the research community to propose novel solutions for detecting objects position in the Indoor environment. Various approaches have been proposed and implemented concerning the indoor positioning systems. This study propose an fuzzy inference based Kalman filter to improve the position estimation in indoor navigation. The presented system is based on FIS based Kalman filter aiming at predicting the actual sensor readings from the available noisy sensor measurements. The proposed approach has two main components, i.e., multi sensor fusion algorithm for positioning estimation and FIS based Kalman filter algorithm. The position estimation module is used to determine the object location in an indoor environment in an accurate way. Similarly, the FIS based Kalman filter is used to control and tune the Kalman filter by considering the previous output as a feedback. The Kalman filter predicts the actual sensor readings from the available noisy readings. To evaluate the proposed approach, the next-generation inertial measurement unit is used to acquire a three-axis gyroscope and accelerometer sensory data. Lastly, the proposed approach's performance has been investigated considering the MAD, RMSE, and MSE metrics. The obtained results illustrate that the FIS based Kalman filter improve the prediction accuracy against the traditional Kalman filter approach. [ABSTRACT FROM AUTHOR]

• The robot navigation map was derived from the planting map of a transplanter. • Correct the navigation errors of a robot due to uneven ground in paddy fields. • Evaluate the navigation system performance through some simulations and tests. The navigation system is a crucial part of a paddy field scouting robot, which directly affects the working performance of the robot. The navigation error of the robot was enlarged by the inclination of the robot, which was caused by the uneven surface of the paddy fields. In this study, a map-based navigation system was proposed. The robot navigation map was derived from the planting map of a transplanter. An IMU was integrated with the GNSS to correct the navigation error using the inclination data of the robot through the Kalman filtering technique. A series of simulations and tests were performed to evaluate the performance of the integrated navigation system, including a line following test, a rough road simulation and test, and a row tracking test, as well as a field validation test. The lateral position offset and bearing angle deviation were measured and analyzed to assess the performance. The test results showed that the integrated navigation system significantly reduced the lateral position offset and bearing angle variation by 38.3 % and 26.7 % respectively as compared to the control group without the IMU correction. In the field validation test, the average lateral position offset was 5.93 cm, which was deemed acceptable for paddy field scouting operation in terms of navigation accuracy. In conclusion, the proposed integrated navigation system could be readily applied to the paddy field scouting robot to minimize navigation errors due to uneven ground and random inclination. [ABSTRACT FROM AUTHOR]

• The perceived overall workload is higher in urban areas and at night compared to driving in rural areas and at daytime. • Young drivers undergo higher perceived distraction by small navigation system displays compared to large ones. • Driving at night has higher perceived mental demand compared to daytime driving. • Rural areas have better perceived driving performance than urban areas. • Large navigation system displays have better perceived performance than small navigation system displays. Driver distraction is a major cause of road crashes and has a great influence on road safety. In vehicles, one of the common distracting sources is navigation systems (NSs). The navigation system (NS) can distract the driver due to following directions and reading the provided information through its display. These tasks take the driver's attention from the primary task of driving and may cause poor driving performance, increasing the risk of crashes. In this paper, the effect of the environment (i.e., urban areas and rural areas), the navigation system display (NSD) size, environmental illumination, and gender on young drivers between the ages of 18 and 29 years mental workload was investigated using a simulated driving experiment. To evaluate each driving condition, the NASA-TLX (NASA Task Load Index) workload assessment tool, and a distraction evaluation element, were introduced and used to assess the overall workload, the workload subscales and the distraction by the NSD. The assessment showed a higher perceived overall workload for urban areas and night driving as compared to a rural areas and daytime driving. Moreover, the results showed a greater perceived distraction by the NSD in urban areas compared to driving in rural areas. The subjects also felt distracted when using the small NS compared to using the large NS. The study concluded that urban areas driving, and night driving creates higher perceived workload than rural areas and daytime driving. Furthermore, small NSD leads to more perceived distraction than large NSD while driving. The NSD designers may utilize this research findings to optimize NSD designs to improve driving safety, performance and comfort. Moreover, this study contributes to our understanding of the effect of the NSD size on driving workload and distraction. [ABSTRACT FROM AUTHOR]

Introduction: Using a navigation system in open-wedge high tibial osteotomy (OWHTO) has higher accuracy than using the conventional method. However, unintentional over- and under-correction still exist. This study aimed to compare various factors related to over- and under-correction and to assess their predictive factors in the preoperative radiographs.Materials and Methods: This study involved 96 knees. The difference in the hip-knee-ankle angle (HKA) between the intraoperative navigation system and postoperative radiograph was termed navigation correction loss (NCL). Knees with absolute values of NCL (|NCL|) ≦ 1.5° and |NCL| > 1.5° were categorised into acceptable (n = 46) and outlier (n = 50) groups, respectively. The differences in joint line convergence angle (JLCA) between varus and valgus radiographs, varus JLCA, valgus JLCA, standing JLCA and standing HKA were compared between the two groups. Clinical results were evaluated using the American Knee Society (AKS) scores.Results: The mean intraoperative HKA in the navigation system was - 3.8 ± 1.8°, and that in the postoperative standing radiograph was - 4.2 ± 2.5° (p = 0.033). Preoperative varus, valgus and standing JLCA were higher in the outlier group (p = 0.018, p = 0.020 and p = 0.001, respectively). Logistic regression analyses for preoperative factors of |NCL| ≦ 1.5° showed that standing JLCA was a determining factor, with an odds ratio of 1.334 (confidence interval was 1.087-1.637, p = 0.006). AKS score was higher in the acceptable group (p = 0.040) postoperatively.Conclusions: Higher preoperative standing JLCA was the predictive factor of |NCL| > 1.5°. This factor reduced the rates of under- and over-correction and resulted in better AKS score in OWHTO. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to test the hypotheses that the joint distraction force changes the three-dimensional articulation between the femur and the tibia and that the presence of posterior cruciate ligament (PCL) affects the three-dimensional articulation during joint gap evaluation in total knee arthroplasty (TKA).Methods: Cruciate-retaining TKA procedures were performed on 6 cadaveric knees using a navigation system. The joint center gap and varus ligament balance were measured using Offset Repo-Tensor® with the knee at 90° of flexion before and after PCL resection for joint distraction forces of 89, 178, and 266 N. The three-dimensional location of the tibia relative to the femur and the axial rotational angle of the tibia were also assessed.Results: Regardless of PCL resection, the joint center gap became larger (p = 0.002, p = 0.020) and varus ligament balance became more varus (p = 0.002, p = 0.002) with increasing joint distraction force, whereas the tibia was more internally rotated (p = 0.015, p = 0.009) and more anteriorly located (p = 0.004, p = 0.009). The tibia was more internally rotated (p = 0.015) and more posteriorly located (p = 0.026) after PCL resection than before resection.Conclusions: Joint distraction force changed three-dimensional articulation regardless of PCL preservation. PCL function was revealed as a factor restraining both tibial posterior translation and internal rotation. Surgeons should recognize that joint gap evaluation using a tensor device is subject to three-dimensional changes depending on the magnitude of the joint distraction force. [ABSTRACT FROM AUTHOR]

Purpose: In total knee arthroplasty (TKA), it is important to obtain an appropriate flexion-extension gap. The extension gap is expanded by posteromedial vertical capsulotomy (PMVC). This study aimed to evaluate the increase in the extension gap by PMVC using a navigation system.Methods: In posterior stabilized (PS)-type TKA, PMVC was performed in 37 knees. The medial extension gap at 0° and flexion gap at 90° flexion of the knee joint using the navigation system before and after PMVC were measured.Results: The extension gap before the PMVC was 5.3 ± 2.9 mm. After PMVC, the extension gap had significantly increased to 8.0 ± 2.8 mm (p < 0.001). In addition, the flexion gap was 8.1 ± 2.7 mm before the PMVC, but it was 8.7 ± 2.8 mm after the PMVC, and the flexion gap was not enlarged (n.s.).Conclusion: In PS-type TKA, it is possible to obtain selective expansion of about 2.7 mm of the extension gap by PMVC. Therefore, gap balance can be acquired by soft-tissue treatment while preserving the bone. The PMVC was a useful method for acquiring gap balance and preserving the bone stock.Level Of Evidence: IV. [ABSTRACT FROM AUTHOR]

Background: Inadequate acetabular component orientation is associated with postoperative impingement, dislocation, and accelerated polyethylene wear. Computed tomography (CT)-based navigation systems provide accuracy for total hip arthroplasty (THA) but are not available in all facilities. Accelerometer-based navigation systems are inexpensive, but their accuracy remains undetermined. This study compares the accuracy of cup orientation in THA using CT-based and accelerometer-based navigation systems. Methods: This retrospective study included 35 consecutive patients (11 males, 24 females; mean age, 65 years) who underwent primary cementless THA via an anterolateral approach in the supine position. Both CT-based and accelerometer-based navigation systems were used simultaneously. The accuracy of cup orientation was compared between the two systems using postoperative CT. Results: The accuracy of cup inclination was 2.7° ± 2.0° in the CT-based group and 3.3° ± 2.4° in the accelerometer-based group. The accuracy of cup anteversion was 2.8° ± 2.6° in the CT-based group and 3.4° ± 2.2° in the accelerometer-based group. No significant difference was observed in cup inclination (p = 0.29) or cup anteversion (p = 0.34) between CT-based and accelerometer-based navigation. Conclusions: The accuracy of cup positioning did not differ significantly between CT-based and accelerometer-based navigation systems. [ABSTRACT FROM AUTHOR]

The multi-mission and multi-working mode of aerospace vehicles requires the navigation system to be flexible, accurate and stable. In aerospace vehicles, a variety of navigation sensors are often used to form a multi-source fault-tolerant integrated navigation system. A multiple source redundancy design method of fuzzy fault-tolerant navigation system is proposed. On the basis of designed fault diagnosis and isolation of each redundant system, the quality factor of each navigation system is calculated through fuzzy evaluation, thus effectively diagnosing and isolating the failure of inertial navigation system and ensuring its accuracy and reliability.The proposed method has good processing capacity for soft and hard faults. The simulated results show that the proposed method-based navigation system has the fault-tolerant performance. In the case of system malfunction, it has better performance compared to the traditional multi-source navigation system and good applicability in different flying stages. [ABSTRACT FROM AUTHOR]

Complex road networks, inaccurate GPS receiver output, low sampling rate and many other associated issues pose real challenges for map matching process. Genetic algorithms have recently been trialed for rendering GPS fix on digital maps. This manuscript introduces an improvised genetic algorithm named as post-processing genetic-inspired map matching (GiMM) algorithm. The proposed GiMM intends to mitigate inherent challenges associated with originally proposed genetic algorithm for map matching. The fitness function used by GiMM makes use of Bucket Dijkstra's and fast dynamic time wrapping (FDTW) algorithms to render GPS information on digital maps. Bucket Dijkstra's suggests the shortest path available in between two points, and FDTW is responsible for comparing two data series. Unlike traditional genetic algorithm for map matching, GiMM was evaluated on sparse as well as dense GPS data. The performance of the GiMM algorithm was evaluated in real time using OpenStreetMap data and GPS dataset mapped onto a road network of 82 km. GiMM uses population size, generation count, accuracy and execution time as input parameters. A maximum accuracy of 99.4% with root-mean-square error 0.06 was observed, whereas a minimum of 60% accuracy was observed at 0.47 root-mean-square error. Number of iterations and population size were concluded to be the most influential parameters for the performance of genetic algorithms for map matching. [ABSTRACT FROM AUTHOR]

Background: Wheelchair users are increasingly using route planners and navigation systems to help them get around the city. The absence of a list of usability criteria for wheelchair user-centred design and recommending geospatial assistive technologies creates uncertainty about the choices to be made by rehabilitation clinicians and geographic information systems specialists. The aim of this study was to compile such a list by identifying usability criteria from standardized questionnaires linked to user interfaces and geospatial assistive technologies (GATs). Material and methods: We conducted a scoping review in ACM Digital Library, Inspec/Compendex and PsycINFO for the period 2005–2016 using keyword strategies. From 84 articles identified, after screening and exclusion procedures, 15 articles were selected. Data were extracted from them and reported in table 1 (relevant questionnaires listed in alphabetical order, type of user interface, population studied, psychometric properties, type of measurement scale and information about the construct, number of subscales and items) and in table 2 (usability criteria up to 20 items for the questionnaires, scales or constructs, pointing criteria as gold standard in physical rehabilitation and as in geographic information). Results: We identified 87 usability criteria in 12 standardized questionnaires in 15 articles (with at least two types of psychometric properties). There are 54 usability criteria that could be used in clinical situations concerning their potential applicability to GATs for wheelchair users: 20 are familiar to rehabilitation clinicians who recommend assistive technologies, 21 are generic to GATs while 13 are specific to mobile applications or voice recognition systems. It remains 34 criteria that are not actually familiar to clinicians: actual use, content (including content-clarity, content-color, content-consistency, content-credibility, content-legibility, content-relevance, content-trustworthy, and content-understandable), control-obviousness, customer service behavior, delivery format, design-application, ease of navigation, entry-point type, everyday words, fingertip-size controls, font, functions-expected, functions-integration, gestalt, graphics, habit, hierarchy, input, network externality, speech characteristics, structure, subtle animation, time spent waiting, transition, user goal orientation and verbosity. Conclusions: More research is needed to develop a questionnaire specific to geospatial assistive technologies for wheelchair users linked with mobile applications and information content. For manual wheelchair users paired with geospatial assistance technology, "effectiveness, efficiency, learnability and satisfaction" are essential criteria for route planning and navigation task. Clinicians can optimize the selection of a geospatial assistance technology considering 16 criteria: appearance, assistance-human support, comfort, ease of holding, ease of use, emotional aspect, endurance, facilitating conditions, intention to use, minimal memory load, physical effort, price value, simplicity, social influence, training and usefulness. Clinicians should have in mind that WC users want to plan a route with as few obstacles as possible. Information on the screen should be accessible to WC users (text, contrast, symbols, graphics, photos, voice, vibration, route views). Hands are occupied with the hand rims, WC users would prefer "listen to verbal" instructions to continue their route instead of looking on their electronic device. 34 criteria are specific for route planning and navigation task. [ABSTRACT FROM AUTHOR]

Background: We present a new, easily applicable approach for the guidance of cryoballoon (CB) pulmonary vein isolation (PVI) procedures that use the combination of a 3D‐mapping system image integration module and computed tomographic (CT)–derived anatomy. The aim of this retrospective, nonrandomized study was to investigate: (a) an alternative use for an established radiofrequency image integration module for cryo procedures; (b) a guidance technology for cryo PVI based on integrated CT anatomy; and (c) its clinical impact. Methods and results: CT left atrium–angiography was performed in 50 consecutive patients before a CB PVI procedure, and a 3D reconstruction of the cardiac anatomy was segmented. A total of 25 patients were treated using conventional fluoroscopy; 25 patients were treated using the 3D image integration technique. In the image integration group, the CARTO3 UNIVU (Biosense Webster) module was used for image integration of 3D anatomy and fluoroscopic imaging. Transseptal puncture and cryo PVI were guided by 3D‐overlay imaging. Procedures were feasible without complications in all patients and cryo PVI procedures were successfully guided using the image integration technique. The intraprocedural time needed to perform image integration was 37 ± 10 seconds. Fluoroscopy time was 31.7 ± 11.7 minutes in the conventional group and 20.1 ± 7.9 minutes in the image integration group (P < .001), procedure time was 116.3 ± 29.0 minutes in the conventional group vs 101.2 ± 20.9 minutes in the 3D group (P = .04). Conclusion: 3D‐overlay guidance of CB PVI is feasible, safe, and applicable in real time with minimal effort. It may significantly reduce radiation exposure by introducing 3D information, known from electroanatomic mapping systems, into cryo PVI procedures. [ABSTRACT FROM AUTHOR]

Background: Limited in vivo kinematic information exists on the effect of clinical-based partial medial and lateral meniscectomy in the context of anterior cruciate ligament (ACL) reconstruction. Hypothesis: In patients with ACL deficiency, partial medial meniscus removal increases the anteroposterior (AP) laxity with compared with those with intact menisci, while partial lateral meniscus removal increases dynamic laxity. In addition, greater postoperative laxity would be identified in patients with partial medial meniscectomy. Study design: Cross-sectional study; Level of evidence, 3. Methods: A total of 164 patients with ACL tears were included in the present study and divided into 4 groups according to the meniscus treatment they underwent: patients with partial lateral meniscectomy (LM group), patients with partial medial meniscectomy (MM group), patients with partial medial and lateral meniscectomy (MLM group), and patients with intact menisci who did not undergo any meniscus treatment (IM group). A further division in 2 new homogeneous groups was made based on the surgical technique: 46 had an isolated single-bundle anatomic ACL reconstruction (ACL group), while 13 underwent a combined single-bundle anatomic ACL reconstruction and partial medial meniscectomy (MM-ACL group). Standard clinical laxities (AP translation at 30° of knee flexion, AP translation at 90° of knee flexion) and pivot-shift (PS) tests were quantified before and after surgery by means of a surgical navigation system dedicated to kinematic assessment. The PS test was quantified through 3 different parameters: the anterior displacement of the lateral tibial compartment (lateral AP); the posterior acceleration of the lateral AP during tibial reduction (posterior acceleration); and finally, the area included by the lateral AP translation with respect to the flexion/extension angle (area). Results: In the ACL-deficient status, the MM group showed a significantly greater tibial translation compared with the IM group (P <.0001 for AP displacement at 30° [AP30] and 90° [AP90] of flexion) and the LM group (P =.002 for AP30 and P <.0001 for AP90). In the PS test, the area of LM group was significantly larger (57%; P =.0175) than the one of the IM group. After ACL reconstruction, AP translation at 30° was restored, while the AP90 remained significantly greater at 1.3 mm (P =.0262) in the MM-ACL group compared with those with intact menisci. Conclusion: Before ACL reconstruction, partial medial meniscectomy increased AP laxity at 30° and 90° and lateral meniscectomy increased dynamic PS laxity with respect to intact menisci. Anatomic single-bundle ACL reconstruction decreased laxities, but a residual anterior translation of 1.3 mm at 90° remained in patients with partial medial meniscectomy, with respect to those with intact menisci. [ABSTRACT FROM AUTHOR]

This article deals with the system of high accuracy positioning of backbone railway network infrastructure and mobile objects of the Republic of Kazakhstan. Using the developments of high accuracy satellite positioning systems and backbone geodetic networks for creating the system of high accuracy positioning in the railway field will allow determining coordinates of backbone network infrastructure and mobile objects and sites of defects revealed with high accuracy and, moreover, will possess the high degree of reliability of conducted measurements of railway infrastructure elements. High accuracy positioning can be provided by the implementation of reference GNSS stations along the backbone railways. The relevance of the study is that the project implementation will allow providing the high accuracy monitoring of defects and/or deviations of the rail track elements from design parameters, movement speed increase and railway transportation safety increase. [ABSTRACT FROM AUTHOR]

Objective: Navigation systems create a connection between imaging data and intraoperative situs, allowing the surgeon to consistently determine the location of instruments and patient anatomy during the surgical procedure. The best results regarding the target registration error (measurement uncertainty) are normally demonstrated using fiducials. This study aimed at investigating a new registration strategy for an electromagnetic navigation device. Methods: For evaluation of an electromagnetic navigation system and comparison of registration with screw markers and automatic registration, we are calculating the target registration error in the region of the paranasal sinuses/anterior and lateral skull base with the use of an electromagnetic navigation system and intraoperative digital volume tomography (cone-beam computed tomography). We carried out 10 registrations on a head model (total n = 150 measurements) and 10 registrations on 4 temporal bone specimens (total n = 160 measurements). Results: All in all, the automatic registration was easy to perform. For the models that were used, a significant difference between an automatic registration and the registration on fiducials was evident for just a limited number of screws. Furthermore, the observed differences varied in terms of the preferential registration procedure. Conclusion: The automatic registration strategy seems to be an alternative to the established methods in artificial and cadaver models of intraoperative scenarios. Using intraoperative imaging, there is an option to resort to this kind of registration as needed. [ABSTRACT FROM AUTHOR]

Cortical bone trajectory (CBT) screw is an attractive technique in terms of fixation strength and less invasiveness. However, the insertion of a pedicle screw penetrating cortical bone on the ideal trajectory is technically demanding. The use of 3-dimensional (3D) patient-matched guides may facilitate the use of this technique. In this technical note and case series, the use of a patient-matched 3D targeting guide for a circumferential fixation with CBT screws is described. Eleven patients with a mean age of 49 years were treated. The MySpine MC (Medacta International SA, Castel San Pietro, Switzerland) technology was used to place CBT screws. A computed tomography (CT) scan–derived 3D model of the patient vertebra was created after the surgeons planned the best custom CBT screw trajectory. Then, scaffolds were printed and used during surgery to guide the screw through the patient pedicle. An intersomatic arthrodesis was also performed. The images of the planned trajectory were superimposed on the postoperative CT scan, confirming the accuracy of the trajectory. The mean deviation from the planned pedicle midpoint was 0.91 mm; 85.2% of the screws were placed within 2° from the planned trajectory. There were 2 grade A (<2 mm) and no grade B or C perforations. The actual entry point was always within 2 mm from the planned entry point. This technical note and case series is the first clinical description on the use of a patient-matched guide for posterior CBT screw placement. The use of these devices could also improve placement accuracy and decrease the risk of nerve damage. [ABSTRACT FROM AUTHOR]

Advanced traveler information systems (ATIS) present traffic information to travelers to assist them in planning their journeys and also provide guidance when on the road. Providing travelers with information affects travel behavior and can result in improved performance and reduced congestion and emissions. However, the success of ATIS depends on, among other factors, whether drivers consider it useful and their particular responses to the provided information. There are, currently, many sources and market players in the traffic information industry producing traffic reports for consumers. The main objective of this paper was to examine whether traffic information provided from different sources are consistent with one other. A variable speed limit system and real-time traffic information system for in-vehicle navigation systems are used as a case study. This comparative analysis was made by superimposing the space-time regions of ground truth measured traffic conditions ("reality") over the space-time regions of the reported information broadcasts. A predictive buffer was also introduced in the assessment. The predictive buffer was included to account for traffic information which could be considered as advance warning messages or correctly predicting and giving congestion information prior to the onset of actual congestion, which otherwise may have been reported as false alarms. This was motivated by the fact that optimal control approaches include the prediction of congestion in their control strategies. The methods developed in this research work have been applied to a real world problem to prove its applicability. [ABSTRACT FROM AUTHOR]