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The Mw 6.2 Mamuju-Majene earthquake occurred on 14 January 2021, with the epicenter at 118.890°E, 2.972°S. The shaking caused severe damage in West Sulawesi, especially in the Mamuju and Majene cities. Most of the coseismic slip distribution of the Mamuju-Majene Earthquake is derived from the daily solutions, which might include early postseismic deformation. Therefore, we conducted a coseismic slip model using kinematic solution based on Global Navigation Satellite System (GNSS) to determine the best coseismic slip values and model distribution. Our analysis indicates that the coseismic displacement from the kinematic solution is higher than the static solution. The GNSS data was utilized for inversion analysis, considering two potential fault sources, they are the Makassar Strait Central Fault and the Mamuju Fault. We found a larger misfit between the observed data and the model generated on static and kinematic solutions along the Makassar Strait Central Fault. Based on the kinematic solution, the coseismic slip distribution represents that fault rupture spreading along a north-south orientation, while the static solution is centered in the northern part. The maximum coseismic slip from each kinematic and static solution is 0.29 m and 0.11 m, respectively. Meanwhile, the seismic moment generated from the kinematic solution is 1.5 × 1026 N m (equivalent to Mw 6.75), which is greater than the static solution of 2.4 × 1025 N m (equivalent to Mw 6.22). [ABSTRACT FROM AUTHOR]

Despite increased awareness of the multifactorial nature of Hamstring Strain Injury (HSI), the role of running biomechanics remains unclear. The aim of this systematic review was to investigate whether an association exists between running biomechanics and HSI. Five databases were searched from inception to January 2021. Eligibility criteria included epidemiological studies that provide data on running biomechanics in athletes who have sustained a HSI (retrospectively or prospectively) and compared to control data. Searches yielded 4,798 articles. Twelve met the selection criteria. Biomechanical analysis differed considerably across studies, thus meta-analyses was not possible. Studies largely found either no differences or contradicting findings between running biomechanics of athletes who have sustained a HSI (retrospectively or prospectively) and controls, with the exception of lateral trunk kinematics and horizontal propulsive forces. It is important to note some concern regarding the quality of included studies, particularly sample size, increasing the risk of bias associated with results. Further research utilising validated methods of biomechanical analysis, is needed to determine if an association exists between running biomechanics and HSI. Until then, definitive conclusions cannot be drawn as to whether specific biomechanical interventions should be included in injury prevention and/or rehabilitation programmes. [ABSTRACT FROM AUTHOR]

In cross-country ski skating, both the G2 and G4 sub-techniques involve one pole push for every second ski push but are used at largely different speed-slope ranges. The aim of this study was to compare temporal and kinematic patterns between G2 and G4 at both identical and different speed-slope conditions. A mixed model was used to analyse spatio-temporal parameters, while a combination of dynamic time warping and statistical parametric mapping was used to compare time traces. Main spatio-temporal parameters, such as cycle time, ski contact time and swing time, differed between G2 and G4 (all p < 0.01). Moreover, two forward and more pronounced acceleration phases of the centre of mass (CoM) were visible in G4 while only one acceleration phase was present in G2. The more continuous propulsion in G2 allows for maintaining a more constant speed at steep slopes and low speeds where this sub-technique is preferred. In contrast, the achievement of high speeds while skiing on flatter terrain seem to require more dynamic motion with shorter, more explosive propulsion periods allowed for in G4. In conclusion, G2 and G4 are two unique movements as characterised by fundamentally different CoM motion and should be denoted as two different sub-techniques. [ABSTRACT FROM AUTHOR]

Background: Diabetic Peripheral Neuropathy (DPN) disrupts body and movement biomechanics, increases mechanical stress during walking, and predisposes individuals to injuries owing to the repetitive effects of these stresses. Aims: This study aimed to assess and compare the impact of neuropathy on gait and pelvic kinematics in individuals with DPN. Methods: This case-control study included two groups: 23 individuals diagnosed with DPN aged between 35–70 and 23 healthy individuals aged–35–70. The BTS-G, a wireless motion sensor, was used to assess the time-distance characteristics of walking in all participants. The system analyzed data pertaining to walking speed, cadence, percentages of stance and swing phases, durations of walking cycles, double-step lengths, pelvic tilt, obliquity, and rotation symmetries. Results: There were no statistically significant differences between the groups in cadence, left and right stance phase percentages, or left and right swing phase percentages (p > 0.05). However, significant differences were observed between the groups in terms of speed, left and right walking cycle durations, and left and right double-step lengths (p < 0.05). Additionally, no statistically significant difference was found between the groups in pelvic tilt symmetry and left and right pelvic tilt range of motion values (p > 0.05). Nevertheless, significant differences were identified between the groups in pelvic obliquity symmetry, pelvic rotation symmetry, left and right pelvic obliquity range of motion, and left and right pelvic rotation range of motion values (p < 0.05). Conclusions: The findings of this study suggest that individuals with DPN exhibit decreased walking speed, prolonged gait cycle duration, increased double step length, and reduced pelvic obliquity and rotation range of motion. [ABSTRACT FROM AUTHOR]

The advancement in depth-sensor technology increased the potential for the clinical use of markerless three-dimensional motion analysis (3DMA); however, the accurate quantification of depth-sensor-based 3DMA on gait characteristics deviating from normal patterns is unclear. This study investigated the concurrent validity of the measurements of compensatory movements measured by depth-sensor-based 3DMA compared to those measured by marker-based 3DMA. We induced swing-phase compensatory movements due to insufficient toe clearance by restricting unilateral ankle and knee joint movements in healthy individuals. Thirty-two healthy young adults (nineteen males, aged 20.4   ±   2.0 years, height 164.4   ±   9.8 cm, weight 60.0   ±   9.3 kg [average ± standard deviation]) walked the 6 m walkway in slow speed, very slow speed, and knee–ankle–foot orthosis (KAFO; participants wore KAFOs on the right leg) conditions. Gait kinematics were measured with marker-based and depth-sensor-based 3DMA systems. The intraclass correlation coefficient (ICC3,1) was used to measure the relative agreement between depth-sensor-based and marker-based 3DMA and demonstrated good or moderate validity for swing-phase compensatory movement measurement. Additionally, the ICC2,1 measured absolute agreement between the systems and showed lower validity than the ICC3,1. The measurement errors for contralateral vaulting, trunk lateral flexion, hip hiking, swing-side hip abduction, and circumduction between instruments were 0.01 m, 1.30°, 1.99°, 2.37°, and 1.53°, respectively. Depth-sensor-based 3DMA is useful for determining swing-phase compensatory movements, although the possibility of missing a slight measurement error of 1–2° must be considered. [ABSTRACT FROM AUTHOR]

Approach: Intermittent incremental tests (ITT), intermittent tests (IT), and continuous tests (CT) provide physiological parameters along with the corresponding swimming speeds (v), which are valuable for decisionmaking by coaches. Purpose: This study aimed to summarise and compare the effectiveness of ITT, IT, and CT in monitoring physiological parameters -- oxygen uptake (VO2), the blood lactate concentration ([La-]), and heart rate (HR) -- as well as their associated v. Methods: The PubMed, EMBASE, and Web of Science databases were searched for complete studies published in English, from 1 January 2000 to 24 January 2024. Eleven studies (n = 164 swimmers) fulfilled the inclusion criteria. A meta-analysis was performed. Results: The results of the studies were homogeneous (p > 0.05) when v was also similar between the tests: ITT compared with CT (7 studies, n = 88 swimmers) VO2 0.03 ± 0.15 mL·kg-1·minute-1, I² = 0%, p = 0.99; v 0.08 ± 0.14 m·s-1, I² = 0%, p = 0.89; IT compared with CT (3 studies, n = 44 swimmers) [La-] 0.12 ± 0.21 mmol·L-1, I² = 0%, p = 0.64; HR -0.32 ± 0.2 beats·minute-1, I² = 0%, p = 0.37; v 0.08 ± 0.14 m·s-1, I² = 0.00%, p = 0.89). Conclusions: The VO2 results for the comparisons between IT and CT, and the [La-] and HR results for comparisons between IT and CT were similar when: (i) the v was also similar between the tests, and (ii) the duration of the tests was long enough to obtain more stable physiological data. [ABSTRACT FROM AUTHOR]

Snake robots have broad application potential, but their motion-control and motion-planning problems are extremely challenging due to the high redundancy of degrees of freedom (DoFs), and the lack of complete system tools further hinders the research of snake robots. In this paper, a coordinate system and a kinematic model were established based on the D-H method for snake robots. The rhythm-generation model for multimodal motion gait and a novel sliding-window five-point interpolation-derivative model were proposed based on a bio-inspired central pattern generator (CPG) model. A prototype and simulator were constructed based on the designed snake robot models to achieve the multimodal motion gait for the snake robot and improve its environmental adaptability. Furthermore, a novel structure–drive–perception–control integration snake robot system (SnakeSys) was built based on the robot-operating system (ROS). Finally, the effectiveness, feasibility, and accuracy of the kinematic model and control model in motion control and information perception were verified through simulations and experiments. We open sourced SnakeSys so that relevant researchers or developers can directly utilize or further develop it. [ABSTRACT FROM AUTHOR]

Background: This study aimed to identify and quantify the kinematic and kinetic gait deviations in post-stroke hemiplegic patients with matched healthy controls using Statistical Parametric Mapping (SPM). Methods: Fifteen chronic stroke patients [4 females, 11 males; age 53.7 (standard deviation 12.2) years; body mass 65.4 (10.4) kg; standing height 168.5 (9.6) cm] and 15 matched healthy controls [4 females, 11 males; age 52.9 (11.7) years; body weight 66.5 (10.7) years; standing height 168.3 (8.8) cm] were recruited. In a 10-m walking task, joint angles, ground reaction forces (GRF), and joint moments were collected, analyzed, and compared using SPM for an entire gait cycle. Results: Generally, when comparing the stroke patients' affected (hemiplegic) and less-affected (contralateral) limbs with the control group, SPM identified significant differences in the late stance phase and early swing phase in the joint angles and moments in bilateral limbs (all p < 0.005). In addition, the vertical and anteroposterior components of GRF were significantly different in various periods of the stance phase (all p < 0.005), while the mediolateral component showed no differences between the two groups. Conclusion: SPM was able to detect abnormal gait patterns in both the affected and less-affected limbs of stroke patients with significant differences when compared with matched controls. The findings draw attention to significant quantifiable gait deviations in the less-affected post-stroke limb with the potential impact to inform gait retraining strategies for clinicians and physiotherapists. [ABSTRACT FROM AUTHOR]

With expertise, athletes develop motor strategies that enhance sports performance or reduce functional costs. Motor variability is known as a relevant way to characterize these strategies in athletes with different levels of expertise. The aim of this scoping review is to gather and discuss the latest advances in the impact of expertise on motor variability during sports‐related tasks. A search encompassing three databases, Medline, SportDiscus, and Academic Search Complete, was performed. Our research methodology included three core themes: motor variability, laboratory instruments, and sports. Motor variability metrics (e.g., standard deviation and approximate entropy) and laboratory instruments (e.g., motion capture system, EMG, and force plate) were compiled. Athletes' expertise was defined by the time of deliberate practice, the performance results, or the level in which they performed. Overall, 48 of the 59 included studies determined that higher‐skilled athletes had lesser motor variability than lower‐skilled athletes. This difference in motor variability between skill levels was present within individual athletes (intra‐individual) and between athletes (inter‐individual). This result was independent of the criteria used to define expertise, the type of instrumentation used, and the metrics used to quantify motor variability. [ABSTRACT FROM AUTHOR]

This study introduces a novel modular soft actuator designed for an anthropomorphic robotic finger that addresses the need for adaptive behavior and precise joint-angle control. The key innovation is its modular design, which enables independent pressure regulation in each air chamber, thus achieving superior precision compared to traditional PneuNets soft actuators. A rigid skeleton is integrated to enhance force transmission and measurement capabilities and thus ensure effective force handling and transmission within each module. The versatility of the actuator is demonstrated through its adaptability in various scenarios, and its features include adaptive positional control achieved by modulating the inflation in each air chamber. This research includes kinematic and kinetostatic analyses to ensure precise control of joint angles and forces at the finger's endpoint. Experimental results confirm the actuator's excellent performance and adaptability, providing valuable insights for advancing soft-actuator technology. The findings suggest significant potential for this actuator in diverse applications, emphasizing its role in the future development of precise and adaptable robotic systems. [ABSTRACT FROM AUTHOR]

The Virtual Track Train (VTT) represents an innovative urban public transportation system that combines tire-based running gears with rail transit management. Effective control of such a system necessitates precise state estimation, a task rendered complex by the multi-articulated nature of the vehicles. This study addresses the challenge by focusing on state estimation for the first unit under significant interference, introducing a fusion state estimation strategy utilizing Gaussian Process Regression (GPR) and Interacting Multiple Model (IMM) techniques. First, a joint model for the first unit is established, comprising the dynamics model as the main model and a residual model constructed based on GPR to accommodate the main model's error. The proposed fusion strategy comprises two components: a kinematic model-based method for handling transient and high-acceleration phases, and a joint-model-based method suitable for near-steady-state and low-acceleration conditions. The IMM method is employed to integrate these two approaches. Subsequent units' states are computed from the first unit's state, articulation angles, and yaw rates' filtered data. Validation through hardware-in-the-loop (HIL) simulation demonstrates the strategy's efficacy, achieving high accuracy with an average lateral speed estimation error below 0.02 m/s and a maximum error not exceeding 0.22 m/s. Additionally, the impact on VTT control performance after incorporating state estimation is minimal, with a reduction of only 3–6%. [ABSTRACT FROM AUTHOR]

The stability of the robot's performance is very important, especially for the wheeled mobile robots that use swerve drives, which need kinematic control to reach the destination point. The study of robot movement known as kinematics is based on an examination of the geometric structure of the robot, with no consideration given to the mass, force, or acceleration that the robot experiences during movement. This study aims to model and simulate the kinematic control design of a wheeled robot that uses a swerve drive. This robot uses BLDC motor actuator so that the robot can reach its destination very quickly and steadily. The test is carried out by simulating and comparing the performance response using BLDC motors and DC motors. According to the testing and trials, the robot can reach its destination by modeling its kinematic control, and BLDC motors are found to be more reliable and efficient for driving and steering than DC motors. [ABSTRACT FROM AUTHOR]

Background: Patients with foot drop may need compensatory mechanisms to improve their gait. Although several gait analysis parameters have been studied in these individuals, no prior research has examined their joint contact force. Thus, this study investigated multiple gait analysis parameters and the joint contact force in patients with foot drop.Methods: This experimental study recruited twenty individuals aged 15 to 60 (mean value 56.4 ± 3.68) with foot drop disorders. A control group was also matched with the first group based on age, height, and gender. The participants were instructed to walk along a 12-meter path. A motion analysis system with eight high-speed cameras and a Kistler force plate was used. During gait analysis, various parameters were measured, such as spatiotemporal, peak forces applied on the leg, range of motions, moments applied on the lower limbs, and joint contact forces.Results: The mean values of stride length and speed for normal subjects were 1.32±0.2 m and 1.24 ± 0.177 m/s, respectively, compared to 0.961±0.24 m and 0.686 ± 0.25 m/s for foot drop subjects (p-value = 0.00). The joint contact force components of the ankle joint increased significantly in foot drop subjects compared to normal subjects.Conclusion: The joint contact forces of the ankle joint increased significantly in foot drop patients, which should be considered in the rehabilitation treatment of these patients.

Background: The knee joint must adapt to the changes in walking speed to stabilize the stance phase and provide fluency in the swing phase.Objective: This study aimed to report a comparison of the gait patterns of transfemoral amputees using a novel mechanical prosthetic knee that can adapt automatically to different walking speeds with 3R60 and 3R15 knee prostheses.Material and Methods: In this experimental study, biomechanical data were collected from six unilateral trans-femoral amputees walking with three knee prostheses. Gait data were gathered at slow, normal, and fast walking speeds across a 7-meter walkway using the Vicon motion system.Results: The results revealed a significant difference in knee angular velocity during the swing phase between prosthetic knees across three walking speeds (P-value=0.002). Prosthetic knee flexion decreased significantly by increasing walking speed for the novel mechanical auto-adaptive prosthetic knee (P-value

Objective: To determine whether (i) low back loads and/or (ii) kinematic coordination patterns differed across theoretical expert, contextual expert and novice groups when completing both generic and occupation-specific lifts. Background: Experience has been proposed as a factor that could reduce biomechanical exposures in lifting, but the literature reports mixed effects. The inconsistent relationship between experience and exposures may be partially attributable to the broad classification of experience and experimental lifting protocols not replicating the environment where experience was gained. Methods: Purposive sampling was used to recruit 72 participants including theoretical experts (formal training on lifting mechanics), contextual experts (paramedics), and novices. Participants performed 10 barbell and crate (generic) lifts, as well as backboard and stretcher (occupation-specific) lifts while whole-body kinematics and ground reaction forces were collected. Peak low back compression and anteroposterior shear loads normalized to body mass, as well as kinematic coordination patterns, were calculated as dependent variables. Results: No significant differences in low back loads were observed across expertise groups. However, significant differences were seen in kinematic coordination patterns across expertise groups in occupation-specific lifts, but not in generic lifts. Conclusion: Increasing expertise is unlikely to minimize low back loads in lifting. However, contextual expertise did influence lifting kinematics, but only when performing occupationally specific lifts. Application: Contextual expertise may help lifters adopt lifting kinematics that enhance the tolerance of their musculoskeletal system to withstand applied loads, but does not seem to reduce the applied low back loads relative to noncontextual expert groups. [ABSTRACT FROM AUTHOR]

The goal of the study is to analyze the kinematics and provide an EMG analysis of the support limb during an instep kick in adolescent players. We set a video camera, two torque transducers on the knee, and EMG sensors. A sample of 16 adolescent soccer players between 10 and 12 years old performed kicks. The kinematics shows a p = .039 on frontal plane (dominant 15.4 ± 1.8, nondominant 18.8 ± 1.7); the EMG analysis shows a p = .04 on muscular activation timing for the vastus medialis. A difference between the legs on the frontal plane emerges. Moreover, a huge difference on sagittal plane between the adolescent pattern and adult pattern exists (15° in adolescent population, 40° in adult population). The result shows a greater activation of the vastus medialis in the nondominant leg; probably, in this immature pattern, the adolescents use this muscle more than necessary. [ABSTRACT FROM AUTHOR]

The advancement in depth-sensor technology increased the potential for the clinical use of markerless three-dimensional motion analysis (3DMA); however, the accurate quantification of depth-sensor-based 3DMA on gait characteristics deviating from normal patterns is unclear. This study investigated the concurrent validity of the measurements of compensatory movements measured by depth-sensor-based 3DMA compared to those measured by marker-based 3DMA. We induced swing-phase compensatory movements due to insufficient toe clearance by restricting unilateral ankle and knee joint movements in healthy individuals. Thirty-two healthy young adults (nineteen males, aged 20.4 ± 2.0 years, height 164.4 ± 9.8 cm, weight 60.0 ± 9.3 kg [average ± standard deviation]) walked the 6 m walkway in slow speed, very slow speed, and knee–ankle–foot orthosis (KAFO; participants wore KAFOs on the right leg) conditions. Gait kinematics were measured with marker-based and depth-sensor-based 3DMA systems. The intraclass correlation coefficient (ICC3,1) was used to measure the relative agreement between depth-sensor-based and marker-based 3DMA and demonstrated good or moderate validity for swing-phase compensatory movement measurement. Additionally, the ICC2,1 measured absolute agreement between the systems and showed lower validity than the ICC3,1. The measurement errors for contralateral vaulting, trunk lateral flexion, hip hiking, swing-side hip abduction, and circumduction between instruments were 0.01 m, 1.30°, 1.99°, 2.37°, and 1.53°, respectively. Depth-sensor-based 3DMA is useful for determining swing-phase compensatory movements, although the possibility of missing a slight measurement error of 1–2° must be considered.

This paper presents the dynamic modelling and tracking control of a holonomic 3-wheel omni-directional mobile robot. A proportional integral derivative (PID) controller is used, and its performance depends on the dynamic model's accuracy. The controller design for the switched non-linear system is based on both a dynamic model and a kinematic design. A proposed dynamic model averages the contact radius of the 3-wheels. The resultant dynamic model, on average, is non-linear and smooth, serving as a potential solution for model-based control design. The closed-loop simulation results clearly illustrate the dynamic characteristics of the 3-wheels omni-directional mobile robot, offering valuable insights into its behaviour for further analysis and optimisation. Comparative simulation results using MATLAB are presented and demonstrate the effectiveness and legitimacy of the control mechanism.

Abstract Background Kinetic and kinematic gait analysis is increasingly practised as a part of lameness evaluation in dogs. The aim of this study was to examine the normal short- and long-term variation in forelimb gait in sound control dogs (CD) at a walk using seven selected variables of objective kinetic and kinematic gait analyses. Also, to compare the findings in CD to a group of forelimb lame dogs with elbow osteoarthritis (OAD). An additional aim was to test a kinetic based graphic method for lameness detection; symmetry squares (SS). A prospective longitudinal study was carried out on client owned CD and OAD. Clinical and orthopaedic evaluations were performed to ensure soundness and detect and grade lameness. Seven kinetic and kinematic variables and SS were tested for lameness evaluation. The CD were divided into two subgroups, CD1 and CD2, and examined twice: CD1 with two months interval and CD2 with 3–4 h interval. The OAD group was evaluated once and compared to the CD groups’ first examination. Results Thirteen CD and 19 OAD were included. For CD1 and CD2, there were no significant differences in any examined variable between examination occasions. Total peak force/impulse symmetry and fore-hind peak force/impulse symmetry differed significantly between OAD and CD. Symmetry squares had a 74% agreement to subjective orthopaedic evaluations. Conclusions In CD, no difference in the examined variables was seen between examination occasions. Four out of seven objective variables differed significantly between CD and OAD. The graphic SS method might have diagnostic potential for lameness detection, making it possible to detect a shift from lame to non-lame limbs. Potentially, this might be especially helpful in bilaterally lame dogs, which often represent a clinical challenge in lameness evaluation.

Abstract Mechanical alignment (MA) total knee arthroplasty (TKA), with neutral leg alignment, mechanical component alignment, and parallel gaps, has achieved good long-term survival. Patient satisfaction, however, is not always perfect. In contrast to the MA, which aims for an ideal goal for all patients, an alternative has been proposed: kinematic alignment (KA)-TKA. In KA, the articular surface is replicated using components aligning with the three kinematic axes. KA-TKA has been gaining popularity, and in addition to the true or calipered KA, various derivatives, such as restricted KA, soft-tissue respecting KA, and functional alignments, have been introduced. Moreover, the functional approach encompasses several sub-approaches. This somewhat complicated scenario has led to some confusion. Therefore, the terminology needs to be re-organized. The term “personalized alignment (PA)” has been used in contrast to the MA approach, including all approaches other than MA. The term “PA-TKA” should be used comprehensively instead of KA and it represents the recent trends in distinct and unique consideration of each individual case. In addition to a comparison between MA and KA, we suggest that evaluation should be conducted to decide which approach is the best for an individual patient within the “personalized alignment” concept.

The purpose was to determine the impact of both cognitive constraint and neuromuscular fatigue on landing biomechanics in healthy and chronic ankle instability (CAI) participants. Twenty-three male volunteers (13 Control and 10 CAI) performed a single-leg landing task before and immediately after a fatiguing exercise with and without cognitive constraints. Ground Reaction Force (GRF) and Time to Stabilization (TTS) were determined at landing in vertical, anteroposterior (ap) and mediolateral (ml) axes using a force plate. Three-dimensional movements of the hip, knee and ankle were recorded during landing using a motion capture system. Exercise-induced fatigue decreased ankle plantar flexion and inversion and increased knee flexion. Neuromuscular fatigue decreased vertical GRF and increased ml GRF and ap TTS. Cognitive constraint decreased ankle internal rotation and increased knee and hip flexion during the flight phase of landing. Cognitive constraint increased ml GRF and TTS in all three axes. No interaction between factors (group, fatigue, cognitive) were observed. Fatigue and cognitive constraint induced greater knee and hip flexion, revealing higher proximal control during landing. Ankle kinematic suggests a protective strategy in response to fatigue and cognitive constraints. Finally, these two constraints impair dynamic stability that could increase the risk of ankle sprain. [ABSTRACT FROM AUTHOR]

The practice of the wheelchair rugby is becoming more and more worldwide. However, few biomechanical studies have focused on this sport. The aim of this study was to compare kinematic parameters of wheelchair rugby players, classified as defensive players (LP-D) versus offensive players (HP-O). Twenty-nine wheelchair rugby players (17 LP-D and 12 HP-O) performed a 20-m sprint test. The peak velocities, temporal parameters (propulsion phase time, deceleration phase time, cycle time and cycle frequencies) and asymmetries (the difference in peak velocities between the right and the left wheels) were measured at the acceleration and constant peak velocity phases of the sprint by an inertial measurement unit which was placed on each rear wheel. At the acceleration and constant peak velocity phases, peak velocities and cycle frequencies were higher in HP-O players than LP-D players. The deceleration phase times and the cycle times were higher in LP-D players than HP-O players. However, no significant difference in asymmetry was found between LP-D players and HP-O players. The HP-O players showed superior performance than the LP-D players, but they could be more exposed at risk of injury at their upper limbs than LP-D players. [ABSTRACT FROM AUTHOR]

Talonavicular (TN) fusion is a common treatment for TN arthritis or deformity correction. There is incongruous evidence regarding remaining motion at the talocalcaneal and calcaneocuboid joints after TN fusion. Additionally, the effects of a malaligned TN fusion are not well understood and alignment of the fusion may be important for overall foot integrity. This project assessed the kinematic and kinetic effects of neutral and malaligned TN fusions. Ten cadaveric feet were tested on a gait simulator in four conditions: unfused, fused in neutral, fused in varus, and fused in valgus. The fusions were simulated with external fixation hardware. An eight‐camera motion analysis system and a 10‐segment foot model generated kinematic data, and a pressure mat captured pressure data. Simulated TN fusion was achieved in eight feet. From unfused to fused‐neutral, range of motion (ROM) was not eliminated in the adjacent joints, but the positions of the joints changed significantly throughout stance phase. Furthermore, the ROM increased at the tibiotalar joint. Plantar pressure and center of pressure shifted laterally with neutral fusion. The malalignments marginally affected the ROM but changed joint positions throughout stance phase. Pressure patterns were shifted laterally in varus malalignment and medially in valgus malalignment. The residual motion and the altered kinematics at the joints in the triple joint complex after TN fusion may subsequently increase the incidence of arthritis. Clinical significance: This study quantifies the effects of talonavicular fusion and malalignment on the other joints of the triple joint complex. [ABSTRACT FROM AUTHOR]

Background: The knee joint must adapt to the changes in walking speed to stabilize the stance phase and provide fluency in the swing phase. Objective: This study aimed to report a comparison of the gait patterns of transfemoral amputees using a novel mechanical prosthetic knee that can adapt automatically to different walking speeds with 3R60 and 3R15 knee prostheses. Material and Methods: In this experimental study, biomechanical data were collected from six unilateral trans-femoral amputees walking with three knee prostheses. Gait data were gathered at slow, normal, and fast walking speeds across a 7-meter walkway using the Vicon motion system. Results: The results revealed a significant difference in knee angular velocity during the swing phase between prosthetic knees across three walking speeds (P-value=0.002). Prosthetic knee flexion decreased significantly by increasing walking speed for the novel mechanical auto-adaptive prosthetic knee (P-value<0.001). A lower value of hip power during early swing was considered when amputees walked with novel knee prosthesis (P-value<0.00). The intact leg ankle plantar flexion angle or vaulting did not significantly change while walking speed increased in the novel knee prostheses compared to walking with the 3R60 and 3R15 knee prostheses (P-value=0.002 and P-value<0.06, respectively). Conclusion: Based on the results, a novel mechanical auto-adaptive knee prosthesis has advantages compared to the other conventional designs for unilateral trans-femoral amputees walking at different speeds. [ABSTRACT FROM AUTHOR]

Objective: Knowing the morphological, kinematic, and electrophysiological parameters of the smile in healthy individuals may contribute to evaluating, planning, and monitoring the smile reanimation. This study aimed to determine the correlation between 3D morphometric changes, movement kinematics, and muscle activity in the facial soft tissue of healthy individuals. Method: In this cohort study, 20 volunteers were selected from healthy individuals with no facial disorders. During smiling, three‐dimensional face scanning, facial motion capture, and surface electromyography (sEMG) were performed. The average displacement, velocity, and acceleration during facial movements were measured. The mean change in 3D surface morphometry and activation of the zygomaticus major were determined. Results: The volunteers, comprising 10 males and 10 females, had a mean age of 24 ± 10 years; for female, mean age was 23 ± 5 years and for men 26 ± 13 years. Significant correlations were found between kinematic and morphometric data (r = 0.51, p < 0.001), sEMG and morphometric (r = 0.50, p < 0.001) data, and sEMG and kinematic data (r = 0.49, p < 0.002). The maximum acceleration occurred during approximately 65% of the muscle activation time and 64% of the peak muscle activation value. Additionally, the maximum velocity was reached at around 73% of the muscle activation time and 67% of the peak muscle activation value. Furthermore, the maximum displacement values were observed at approximately 88% of the muscle activation time and 76% of the peak muscle activation value. Conclusion: The findings may provide insights into the smile's functional parameters, contribute to understanding facial muscle‐related disorders, and aid in improving the diagnosis and treatment of the smile. Level of Evidence: NA Laryngoscope, 134:3112–3119, 2024 [ABSTRACT FROM AUTHOR]

Background: Kinetic and kinematic gait analysis is increasingly practised as a part of lameness evaluation in dogs. The aim of this study was to examine the normal short- and long-term variation in forelimb gait in sound control dogs (CD) at a walk using seven selected variables of objective kinetic and kinematic gait analyses. Also, to compare the findings in CD to a group of forelimb lame dogs with elbow osteoarthritis (OAD). An additional aim was to test a kinetic based graphic method for lameness detection; symmetry squares (SS). A prospective longitudinal study was carried out on client owned CD and OAD. Clinical and orthopaedic evaluations were performed to ensure soundness and detect and grade lameness. Seven kinetic and kinematic variables and SS were tested for lameness evaluation. The CD were divided into two subgroups, CD1 and CD2, and examined twice: CD1 with two months interval and CD2 with 3–4 h interval. The OAD group was evaluated once and compared to the CD groups' first examination. Results: Thirteen CD and 19 OAD were included. For CD1 and CD2, there were no significant differences in any examined variable between examination occasions. Total peak force/impulse symmetry and fore-hind peak force/impulse symmetry differed significantly between OAD and CD. Symmetry squares had a 74% agreement to subjective orthopaedic evaluations. Conclusions: In CD, no difference in the examined variables was seen between examination occasions. Four out of seven objective variables differed significantly between CD and OAD. The graphic SS method might have diagnostic potential for lameness detection, making it possible to detect a shift from lame to non-lame limbs. Potentially, this might be especially helpful in bilaterally lame dogs, which often represent a clinical challenge in lameness evaluation. [ABSTRACT FROM AUTHOR]

In clinical settings, examining the range of motion (ROM) of trunk rotation and functional tasks is commonly employed as part of musculoskeletal assessments to diagnose low back pain (LBP) cases. This study compared trunk kinematics during functional activities between individuals with and without non-specific LBP. A total of 45 LBP patients and 45 healthy participants were recruited for this research. The Xsens wearable motion capture system was utilized to record movements during axial trunk rotations and activities such as single-leg standing, walking, hurdle steps, squats, and box lifting. During functional tasks, individuals with LBP displayed larger trunk ROMs, except for rotation in the transverse plane (TP) during single-leg standing. Statistically significant differences were observed between the two groups in trunk extension-flexion in the frontal plane (FP) and TP, trunk bending in TP, trunk rotation in FP and TP, single-leg standing in the sagittal plane (SP), walking in SP and FP, hurdle step in TP, and squat in the FP plane (p < 0.05). Individuals with LBP exhibited smaller trunk ROMs during simple trunk rotation movements, whereas larger ROMs were observed during functional tests. These findings shed light on the particular alterations observed in trunk movement and function experienced by individuals with LB. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the criterion validity of the Hawkin Dynamics (HD) wireless dual force platform system for assessing vertical countermovement jump (CMJ) variables, compared with those derived from a Kistler piezoelectric laboratory grade force platform system. During a single testing session, HD force platforms were placed directly on top of 2 adjacent Kistler force platforms to simultaneously collect vertical ground reaction forces produced by 2 male recreational soccer players (age: 29.0 ± 2.8 years, height: 1.79 ± 0.01 m, mass: 85.6 ± 4.7 kg) that performed 25 vertical CMJs each. Sixteen vertical CMJ variables pertaining to jump height (JH), flight time (FT), time-to-take off (TTT), countermovement depth, body weight (BW), propulsive and braking mean, and peak powers, forces, and impulses were compared between systems. Fixed bias was observed for 6 of 16 variables (peak and mean braking power, mean propulsion force, III, FT, and BW), while proportional bias was present for 10 of 16 variables (peak and mean propulsive and braking force, TTT, FT, peak and mean braking power, mean propulsive power, and BW). For all variables regardless of fixed or proportional bias, percentage differences were ≤3.4% between force platform systems, with near perfect to perfect correlations (r or ρ = 0.977-1.000) observed for 15 of 16 variables. The HD dual wireless force platform system can be considered a valid alternative to a piezoelectric laboratory grade force platform system for the collection of vertical CMJ variables, particularly outcome (i.e., JH, reactive strength index modified) and strategy variables (countermovement depth). [ABSTRACT FROM AUTHOR]

Although the measurements of the lumbar spine and pelvic flexion have shown that subjects with radiculopathy exhibited greater decreases of motion when compared with subjects with low back pain, there is still a lack of evidence regarding the changes in flexion relaxation ratio in patients with radiculopathy. The aims of this study were to investigate the flexion relaxation ratio and flexion of the lumbar spine and pelvis in subjects with low back pain (LBP) and LBP with radiculopathy (LBPR) in comparison with healthy subjects (CG—control group). A total of 146 participants were divided in three groups: LBP patients (54 males; 21 females); LBPR patients (26 males; 11 females); and CG subjects (16 males; 18 females). The lumbar spine and pelvis flexion was recorded using optoelectronic motion capture system. The electrical activity of the erector spinae muscles was assessed by surface electromyography during flexion-extension movements. Comparisons between groups were made using one-way ANOVA tests and Mann–Whithney U test with the level of statistical significance at 0.05. The lumbar and pelvic flexion and electromyography of the erector spinae muscle showed significant differences between LBP and LBPR patients compared to CG. Patients LBPR showed significantly smaller angles of lumbar and pelvic flexion compared to LBP patients and CG. An increase in the erector spinae muscle activity during flexion was also observed in patients with radiculopathy. The increased muscular activity of the erector spinae is related to the reduced flexion of the lumbar spine in order to protect the lumbar spine structure. Measurements of trunk, lumbar spine and pelvic flexion, and the flexion relaxation ratio may allow us to predict better outcomes or responsiveness to treatment of LBPR patients in the future. [ABSTRACT FROM AUTHOR]

Aiming at the problem that industrial silt in settling tank was difficult to clean up, a crawler-type underwater dredging robot which can adapt to complex environment was designed. A crawler-type moving mechanism was used by the silt removal robot to adapt to soft mud layer. The stability of the dredging robot driving on flat ground and up and down slopes were analyzed, and the feasible region of the center of buoyancy of dredging robot running stably was obtained. The dynamic model of a dredging robot was built based on RecurDyn simulation software, and different types of terrain environment and working conditions were analyzed when the robot operating underwater. The results indicate that the buoyancy set in the center of buoyancy domain when the stability of the robot is higher. The height of the center of mass of the dredging robot can always remain stable and meet the design requirements. It is confirmed that the dredging robot can stably pass through 15° slopes and 100 mm obstacle, which proves that the design of the dredging robot can adapt to the complex underwater environment. [ABSTRACT FROM AUTHOR]

Background: Biomechanical alterations in patients with low back pain (LBP), as reduced range of motion or strength, do not appear to be exclusively related to the trunk. Thus, studies have investigated biomechanical changes in the hip, due to the proximity of this joint to the low back region. However, the relationship between hip biomechanical changes in patients with LBP is still controversial and needs to be summarized. Therefore, the aim of this study was to systematically review observational studies that used biomechanical assessments in patients with non-specific LBP. Methods: The search for observational studies that evaluated hip biomechanical variables (i.e., range of motion, kinematic, strength, and electromyography) in adults with non-specific acute, subacute, and chronic LBP was performed in the PubMed, Embase, Cinahl and Sportdiscus databases on February 22nd, 2024. Four blocks of descriptors were used: 1) type of study, 2) LBP, 3) hip and 4) biomechanical assessment. Two independent assessors selected eligible studies and extracted the following data: author, year of publication, country, study objective, participant characteristics, outcomes, and results. The methodological quality of the studies was assessed using the Epidemiological Appraisal Instrument and classified as low, moderate, and high. Due to the heterogeneity of the biomechanical assessment and, consequently, of the results among eligible studies, a descriptive analysis was performed. Results: The search strategy returned 338 articles of which 54 were included: nine articles evaluating range of motion, 16 evaluating kinematic, four strength, seven electromyography and 18 evaluating more than one outcome. The studies presented moderate and high methodological quality. Patients with LBP, regardless of symptoms, showed a significant reduction in hip range of motion, especially hip internal rotation, reduction in the time to perform functional activities such as sit-to-stance-to-sit, sit-to-stand or walking, greater activation of the hamstrings and gluteus maximus muscles and weakness of the hip abductor and extensor muscles during specific tests and functional activities compared to healthy individuals. Conclusion: Patients with LBP present changes in range of motion, task execution, activation, and hip muscle strength when compared to healthy individuals. Therefore, clinicians must pay greater attention to the assessment and management of the hip during the treatment of these patients. Systematic review registration: International Prospective Register of Systematic Reviews (PROSPERO) (CRD42020213599). [ABSTRACT FROM AUTHOR]

Mechanical alignment (MA) total knee arthroplasty (TKA), with neutral leg alignment, mechanical component alignment, and parallel gaps, has achieved good long-term survival. Patient satisfaction, however, is not always perfect. In contrast to the MA, which aims for an ideal goal for all patients, an alternative has been proposed: kinematic alignment (KA)-TKA. In KA, the articular surface is replicated using components aligning with the three kinematic axes. KA-TKA has been gaining popularity, and in addition to the true or calipered KA, various derivatives, such as restricted KA, soft-tissue respecting KA, and functional alignments, have been introduced. Moreover, the functional approach encompasses several sub-approaches. This somewhat complicated scenario has led to some confusion. Therefore, the terminology needs to be re-organized. The term "personalized alignment (PA)" has been used in contrast to the MA approach, including all approaches other than MA. The term "PA-TKA" should be used comprehensively instead of KA and it represents the recent trends in distinct and unique consideration of each individual case. In addition to a comparison between MA and KA, we suggest that evaluation should be conducted to decide which approach is the best for an individual patient within the "personalized alignment" concept. [ABSTRACT FROM AUTHOR]

Due to their advantages of good stability, adaptability, and flexibility, multi-legged robots are increasingly important in fields such as rescue, military, and healthcare. This study focuses on the millipede, a multi-segmented organism, and designs a novel multi-segment biomimetic robot based on an in-depth investigation of the millipede's biological characteristics and locomotion mechanisms. Key leg joints of millipede locomotion are targeted, and a mathematical model of the biomimetic robot's leg joint structure is established for kinematic analysis. Furthermore, a central pattern generator (CPG) control strategy is studied for multi-jointed biomimetic millipede robots. Inspired by the millipede's neural system, a simplified single-loop CPG network model is constructed, reducing the number of oscillators from 48 to 16. Experimental trials are conducted using a prototype to test walking in a wave-like gait, walking with a leg removed, and walking on complex terrain. The results demonstrate that under CPG waveform input conditions, the robot can walk stably, and the impact of a leg failure on overall locomotion is acceptable, with minimal speed loss observed when walking on complex terrain. The research on the structure and motion control algorithms of multi-jointed biomimetic robots lays a technical foundation, expanding their potential applications in exploring unknown environments, rescue missions, agriculture, and other fields. [ABSTRACT FROM AUTHOR]

This study aims to identify the characteristics of the takeoff and landing in the round off performance followed by followed by a double back tuck. One gymnast participated in this study, and the data was captured using an camera at a speed of 240 fps and perpendicular to the plane of movement. Data were extracted using the analytical software SkillSpector and Kinovea. The data revealed that the vertical velocity, which was when takeoff (5.9 m/s). This was evident at the maximum height of the center of mass, which was measured (2.3 m). The higher values for the maximum height of the center of mass were the result of a combination of several performance factors, such as the contact angle and the takeoff on the floor with horizontal and faster leg extension. The horizontal velocity at contact was (5.7 m/s) and decreased to (-2.5 m/s) at takeoff. The results of the study indicate that the double back tuck movement involves a reduction in horizontal velocity and an increase in vertical velocity. This is because the horizontal velocity is converted into vertical velocity to raise the body to a great height so that the gymnast can get the time required to execute the skill while flying in the air. The leg muscles also played the dominant role in takeoff and landing through contact angles and takeoff and landing. [ABSTRACT FROM AUTHOR]

Abstract This paper presents a fusion algorithm based on the enhanced RRT* TEB algorithm. The enhanced RRT* algorithm is utilized for generating an optimal global path. Firstly, proposing an adaptive sampling function and extending node bias to accelerate global path generation and mitigate local optimality. Secondly, eliminating path redundancy to minimize path length. Thirdly, imposing constraints on the turning angle of the path to enhance path smoothness. Conducting kinematic modeling of the mobile robot and optimizing the TEB algorithm to align the trajectory with the mobile robot's kinematics. The integration of these two algorithms culminates in the development of a fusion algorithm. Simulation and experimental results demonstrate that, in contrast to the traditional RRT* algorithm, the enhanced RRT* algorithm achieves a 5.8% reduction in path length and a 62.5% decrease in the number of turning points. Utilizing the fusion algorithm for path planning, the mobile robot generates a superior, seamlessly smooth global path, adept at circumventing obstacles. Furthermore, the local trajectory meticulously conforms to the kinematic constraints of the mobile robot.

Purpose The aim of the study was to identify the distinguishing characteristics of the swing movement of the world’s top dancesport couples through kinematic variables. Methods The study involved six world-class and six intermediate dance couples. The couples were asked to execute three identical series of three natural turns of the figure in a Viennese Waltz, all being filmed as they danced to music. Six international experts evaluated all the trials of each couple from the point of view of the technical quality component based on the Absolute Judging System. A triaxial rotational angular velocity measurement (gyroscope) device was placed on the dorsal part of the pelvic girdle and on the posterior part of the thorax of each competitor. Results An analysis of covariance demonstrated that regardless of the sports level, the maximum hip girdle angular rotation velocity in the forward swing movement performed by men was significantly related to the judging score achieved (F1,9 = 11.5; p < 0.05; ηp2 = 0.45). Conclusions The mean squares of the differences of the hip and thoracic spine angular rotation velocity signals were found to be a good criterion for evaluating the swing movement, which is related to the judges’ evaluation. The descriptions of the performance of complex rotational movements obtained in this study can find their application in the analysis, teaching, and evaluation of dance couples. This is one of the first studies in the literature that deals in detail with swing movement in sports dance.

Abstract A novel mesh-free solution is proposed for kinematic shakedown analysis of cohesive soils under repeating loads. For this purpose, the continuous velocity field in the mathematical expression of Koiter’s theorem is discretized by the Radial Point Interpolation Method (RPIM), as a mesh-free approach. The strain rate smoothing technique is implemented in conjunction with the RPIM to satisfy the admissibility conditions at the entire problem domain. Using the nodal integration and the discretized velocity field, the kinematic shakedown problem is expressed as a nonlinear optimization problem. The optimization problem is solved by separation of plastic and non-plastic/rigid zones using a repetitive algorithm. Eventually, the efficiency of the proposed approach is elucidated by solving examples of a strip footing resting on cohesive soil and a cohesive half space pavement under repeating loads.

This paper presents a fusion algorithm based on the enhanced RRT* TEB algorithm. The enhanced RRT* algorithm is utilized for generating an optimal global path. Firstly, proposing an adaptive sampling function and extending node bias to accelerate global path generation and mitigate local optimality. Secondly, eliminating path redundancy to minimize path length. Thirdly, imposing constraints on the turning angle of the path to enhance path smoothness. Conducting kinematic modeling of the mobile robot and optimizing the TEB algorithm to align the trajectory with the mobile robot's kinematics. The integration of these two algorithms culminates in the development of a fusion algorithm. Simulation and experimental results demonstrate that, in contrast to the traditional RRT* algorithm, the enhanced RRT* algorithm achieves a 5.8% reduction in path length and a 62.5% decrease in the number of turning points. Utilizing the fusion algorithm for path planning, the mobile robot generates a superior, seamlessly smooth global path, adept at circumventing obstacles. Furthermore, the local trajectory meticulously conforms to the kinematic constraints of the mobile robot. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to investigate the differences in spatiotemporal gait parameters in patients who underwent surgery for hip fractures when using walking poles and T-canes. Methods: This cross-sectional study enrolled eight patients who underwent surgery for a unilateral hip fracture (mean age of 79.0 ± 7.9 years) and 34 healthy individuals who had no symptoms (mean age of 32.1 ± 6.2 years). The outcome measures were the walking speed, trunk acceleration, and lateral lean angles of the trunk, shoulder and pelvis during walking. The results were compared among the three types of walking aids, namely, a T-cane, double T-canes and walking poles. Results: Acceleration indices step symmetry in the vertical and anteroposterior directions in walking with walking poles were significantly larger than that in walking with a T-cane. These results were common in patients with fractures and healthy individuals. Conclusions: Walking with walking poles might be a more symmetrical gait style than walking with a T-cane in patients who under-went surgery for hip fractures. [ABSTRACT FROM AUTHOR]

Non-linear and dynamic systems analysis of human movement has recently become increasingly widespread with the intention of better reflecting how complexity affects the adaptability of motor systems, especially after a stroke. The main objective of this scoping review was to summarize the non-linear measures used in the analysis of kinetic, kinematic, and EMG data of human movement after stroke. PRISMA-ScR guidelines were followed, establishing the eligibility criteria, the population, the concept, and the contextual framework. The examined studies were published between 1 January 2013 and 12 April 2023, in English or Portuguese, and were indexed in the databases selected for this research: PubMed®, Web of Science®, Institute of Electrical and Electronics Engineers®, Science Direct® and Google Scholar®. In total, 14 of the 763 articles met the inclusion criteria. The non-linear measures identified included entropy (n = 11), fractal analysis (n = 1), the short-term local divergence exponent (n = 1), the maximum Floquet multiplier (n = 1), and the Lyapunov exponent (n = 1). These studies focused on different motor tasks: reaching to grasp (n = 2), reaching to point (n = 1), arm tracking (n = 2), elbow flexion (n = 5), elbow extension (n = 1), wrist and finger extension upward (lifting) (n = 1), knee extension (n = 1), and walking (n = 4). When studying the complexity of human movement in chronic post-stroke adults, entropy measures, particularly sample entropy, were preferred. Kinematic assessment was mainly performed using motion capture systems, with a focus on joint angles of the upper limbs. [ABSTRACT FROM AUTHOR]

The article focuses on the control of an omni-tracked vehicle in a symmetrical fully overlapping track system. The vehicle in question is equipped with four independently controlled tracks. The links of each crawler are equipped with a single rolling roller, fixed at an angle to the direction of the vehicle main axis. The authors propose mathematical description to determine the direction and speed of movement of a single pair of omni-tracks with oppositely arranged rolling rollers. Numerical tests were carried out, the results of which were compared with the mathematical model. The numerical studies were then subjected to experimental verification, using a full-scale prototype. A dynamic direction correction algorithm was also proposed with its effectiveness proved experimentally. [ABSTRACT FROM AUTHOR]