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With solar tracking, it will become possible to generate more energy since the solar panel can maintain a perpendicular profile to the rays of the sun. Even though the initial cost of setting up the tracking system is considerably high, there are cheaper options that have been proposed over time. This research discuss the design and construction of a prototype for a solar tracking system that has a single axis of freedom. Light Dependent Resistors (LDRs) are used for sunlight detection. The control circuit is based on an ATMega328P microcontroller. It was programmed to detect sunlight via the LDRs before actuating the servo to position the solar panel. The solar panel is positioned where it is able to receive maximum light. As compared to other motors, the servo motors are able to maintain their torque at high speed. They are also more efficient with efficiencies in the range of 80-90%. Servos can supply roughly twice their rated torque for short periods. Through tracking, there will be increased exposure of the panel to the sun, making it have increased power output. The trackers can either be dual or single axis trackers. As a single tracking system is cheaper, less complex, and still achieves the required efficiency, so it was used.

The main problem in studying the feasibility of solar systems is the enormous gap between theory and experimental radiation intensity, so to get accurate results there is a need for studying energy production in the site of the system empirically. In this study, the energy production of both fixed PV panel system and the system with single-axis tracking were empirically evaluated in Medina, Saudi Arabia. The two systems had the same 270 Wp PV panel. The fixed system was tilted by 23.5 degrees, and the single-axis tracker was tilted by 26 degrees. Both systems had an azimuth angle of zero degrees. A closedloop three-points controller was used to control the tracker with 120 degrees rotation range. The two systems operated simultaneously in July, and the data were collected for 14 days. The empirical results showed that the tracker increased the generated energy by 48.5% during the testing period. As a comparing method, a modified ASHRAE model was used to estimate the increase in the panel's energy output with and without the single-axis tracker, and RMSE and MBE were calculated. It's been found that the experimental energy generation is 10%, 5% less than the estimation of the modified model for the fixed system and the tracking system, respectively. Finally, based on the analysis, it's been estimated that the singleaxis tracker will increase the generated energy by 22.5% yearly in Medina.

In this paper, a novel evacuated tube solar collector (ETSC) is first designed and built. Then, the impact of adding reflector, reflector plus single-axis sun tracker and reflector plus two-axis su...

The algorithm of the turn of the spacecraft from an initial arbitrary angular position at an arbitrary angular rate to a solar-oriented attitude is investigated. Minimum essential equipment of the motion control system required for the purpose of ensuring maintenance of solar orientation is defined: a solar sensor, a single-axis angular-rate sensor, low-thrust liquid rocket engines. A solution of the problem of defining the spacecraft angular rate vector by the measurements of the deviation of the optical axis of the solar sensor from the sun vector and the single-axis angular-rate sensor is presented. The conditions under which control action on the rocket engines for the purpose of changing the value of the angular-rate vector for the Sun to get into the field of viewing of the solar sensor or for the spacecraft stabilization are defined. Mathematical modeling of the spacecraft attitude control system with the unknown initial state vector of motion is carried out. The results of mathematical modeling confirmed the efficiency of the proposed algorithm in terms of reducing propellant fuel consumption and high-speed performance. In comparison with the known methods of solving the problem of reducing angular speed (a lengthy process with the use of a magnetic system or a fast process with the use of a three-axis angular-rate sensor and rocket engines) the duration of the process of reducing angular speeds is the same as in normal operation, however, at the same time the problem of bringing spacecraft into the solar oriented attitude is solved.

This is an experimental study. As current posterior-substituting (PS) total knee arthroplasties have been reported to incompletely restore intrinsic joint biomechanics of the healthy knee, the recently designed single axis radius PS knee system was introduced to increase posterior femoral translation and promote ligament isometry. As there is a paucity of data available regarding its ability to replicate healthy knee biomechanics, this study aimed to assess joint and articular contact kinematics as well as ligament isometry of the contemporary single axis radius PS knee system. Implant kinematics were measured from 11 cadaveric knees using an in vitro robotic testing system. In addition, medial collateral ligament (MCL) and lateral collateral ligament (LCL) forces were quantified under simulated functional loads during knee flexion for the contemporary PS knee system. Posterior femoral translation between the intact knee and the single axis radius PS knee system differed significantly (p

In the past decade, flexible physical sensors have attracted great attention due to their wide applications in many emerging areas including health-monitoring, human-machine interfaces, smart robots, and entertainment. However, conventional sensors are typically designed to respond to a specific stimulus or a deformation along only one single axis, while directional tracking and accurate monitoring of complex multi-axis stimuli is more critical in practical applications. Multidimensional sensors with distinguishable signals for simultaneous detection of complex postures and movements in multiple directions are highly demanded for the development of wearable electronics. Recently, many efforts have been devoted to the design and fabrication of multidimensional sensors that are capable of distinguishing stimuli from different directions accurately. Benefiting from their unique decoupling mechanisms, anisotropic architectures have been proved to be promising structures for multidimensional sensing. This review summarizes the present state and advances of the design and preparation strategies for fabricating multidimensional sensors based on anisotropic conducting networks. The fabrication strategies of different anisotropic structures, the working mechanism of various types of multidimensional sensing and their corresponding unique applications are presented and discussed. The potential challenges faced by multidimensional sensors are revealed to provide an insightful outlook for the future development.

The performance of solar photovoltaic systems can be improved if solar modules are kept perpendicular to the direction of solar radiation. Therefore, an accurate solar tracker system is important to continuously orientate solar modules to be always perpendicular to the solar radiation throughout the day. This paper presents the development and testing of a selfadjusting single-axis solar tracking system using two photovoltaic cells as photosensors. A prototype of the single-axis solar tracking system is built and tested based on continuous tracking method to the sun’s position throughout the day. An Arduino UNO microcontroller, a servo motor, and photovoltaic cells are selected as the components of the prototype. As this is an active tracking system, the orientation of the tracker receiver surface depends on the feedback received from the photosensors. Outdoor tests were carried out under clear skies at Kota Damansara, Malaysia (3.1467512 N, 101.5740615 E). The tracking inaccuracy is less than 5% with the maximum being 4.12%.

This work examined predictions of the interpolation of familiar views (IFV) account of object recognition performance in 5-month-olds. Infants were familiarized to an object either from a single viewpoint or from multiple viewpoints varying in rotation around a single axis. Object recognition was then tested in both conditions with the same object rotated around a novel axis. Infants in the multiple-views condition recognized the object, whereas infants in the single-view condition provided no evidence for recognition. Under the same 2 familiarization conditions, infants in a 2nd experiment treated as novel an object that differed in only 1 component from the familiar object. Infants' object recognition is enhanced by experience with multiple views, even when that experience is around an orthogonal axis of rotation, and infants are sensitive to even subtle shape differences between components of similar objects. In general, infants' performance does not accord with the predictions of the IFV model of object recognition. These findings motivate the extension of future research and theory beyond the limits of strictly interpolative mechanisms.

The kinematics of human knee joint mainly includes the all degree of freedom motion of human knee joint. The human knee joint is the most complex structure of human anatomy and thus it also has high risk of failure. This joint may fail due to failure in ligaments, bone or any other component of the knee joint. Thus, the motion can be restored through the application of prosthetic knee joint. By comparing various single axis and polycentric prosthetic knee designs on the basis of maximum stress induced, manoeuvrability, weight and an optimal model could be developed that will not only have lightweight but will also include easy and low-cost manufacturing. Simulation-based finite element analysis was done on a single axis and two polycentric knee prosthetic knee designs using ANSYS WORKBENCH 18.1.

The purpose of designing a spacecraft Altitude and dynamic control models play an important role in an interplanetary space mission. Particular emphasis is controlling spacecraft Altitude by sail tilting and shifting. In addition, investigate an uncertain balance amongst the centre of pressure and centre of mass on a single axis gimbaled control. Implies a method of Monte Carlo is with standing a significant of solar pressure disturbance torque in deep space mission. A flight test experiment drives in a Low Earth Orbit (LEO), hence, authenticate the source of solar sailing is also suggested. Parameters are incorporating to study and demonstrate the various principals and methods involved in altitude control design and dynamic modeling at LEO. Mitigation of disturbance torques was also examined.

A low cost DC power data logger was designed. It could log data about generated solar energy from two solar systems. The power was measured indirectly. Calculation of power and energy was made every 255 ms. They were averaged and logged with interval one minute. The data logger was made in order to analyze the operation of different solar systems types: fixed mount vs. single axis, single axis vs. double axis, solar system with PWM vs. system with MPPT controller.

Objectives Microelectrode arrays offer a means to probe the functional circuitry of the brain and the promise of cortical neuroprosthesis for individuals suffering from paralysis or limb loss. These devices are typically comprised of one or more shanks incorporating microelectrode sites, where the shanks are positioned by inserting the devices along a straight path that is normal to the brain surface. The lack of consistent long-term chronic recording technology has driven interest in novel probe design and approaches that go beyond the standard insertion approach that is limited to a single velocity or axis. This review offers a description of typical approaches and associated limitations and surveys emergent methods for implantation of microelectrode arrays, in particular those new approaches that leverage embedded microactuators and extend the insertion direction beyond a single axis. Materials and methods This review paper surveys the current technologies that enable probe implantation, repositioning, and the capability to record/stimulate from a tissue volume. A comprehensive literature search was performed using PubMed, Web of Science, and Google Scholar. Results There has been substantial innovation in the development of microscale and embedded technology that enables probe repositioning to maintain quality recordings in the brain. Innovations in material science have resulted in novel strategies for deployable structures that can record from or stimulate a tissue volume. Moreover, new developments involving magnetically steerable catheters and needles offer an alternative approach to "pull" rather than "push" a probe into the tissue. Conclusion We envision the emergence of a new generation of probes and insertion methodologies for neuromodulation applications that enable reliable chronic performance from devices that can be positioned virtually anywhere in the brain.

The quest to increase the energy yield of solar PV farms has led to extensive research on bifacial modules and tracking systems. Previous studies have shown ~12% increase in power for single-axis tracking of standalone bifacial PV modules, but the corresponding gain for bifacial solar farms remains unknown. In this paper, we demonstrate the modeling and physics of single-axis tracking bifacial PV farms that include the essential aspect of mutual shading between the rows of PV panels. Our results show that single-axis tracking bifacial farms outperform fixed mono/bifacial for locations and times with higher direct light fraction. The worldwide maps show a range of yearly power gain from 10-20% for latitudes > 40°. Overall, a judicious deployment of single-axis tracking bifacial solar PV farms would offer immense potential in energy yield maximization and eventual LCOE minimization.

Due to the shading of PV panels, the normal growth of high-illumination-loving plants can not be met, only low-illumination-loving plants are planted in the greenhouse. Aiming at improving this phenomenon, this paper analyzes the characteristics of light demand of the plants, and reveals the principle of agricultural photovoltaic complementary by using the characteristics of light saturation. On this basis, the paper combines with the technical characteristics of the single axis tracking photovoltaic system, according to the light conditions to optimize the photovoltaic angle, to change the light characteristics of the greenhouse, so as to solve the coupling problem between agriculture and photovoltaic. Finally, this paper gives an optimization analysis by taking a 50kW photovoltaic greenhouse as an application scenario. The result shows that 31% improvement of the comprehensive benefits are achieved, which proves that the method in this paper is feasible.

Subtalar joint biomechanics are primarily driven by the shape of the articulations with contributions from the surrounding soft tissues. The joint motion occurs about a single axis oriented medially and superiorly. Joint contact forces change during different stages of gait and are affected by hindfoot alignment and traumatic alterations to their normal anatomy. A valgus subtalar joint axis is likely a contributing, and perhaps primary, risk factor for progression to adult acquired flat foot. The subtalar joint axis also contributes to the clinical picture of a cavus foot and a special subset of patients with dynamic varus.

Every person has different location of veins, some veins are easily detected because it is visible due to thin tissue, and the other are invisible. This different location of veins causes intravenous access procedures and the procreas of intravenous therapy become longer. Multi-distance vein projections aim to simplify the measurement process where the device and object do not have to be at a certain distance. Some research that has been done especially for real-time vein projection does not conduct how the characteristics of projection at different distances. In this paper, we propose a method for performing multi-distance real-time back-projection by using the intersection between camera and projector. This method equiped with an ultrasonic distance sensor to identify the projection characteristic in any distance. In its implementation, this method is able to project at a distance of 20-40 cm with a maximum projection error of 0.6 mm. The measurement angle tolerance between the object and the device is ±5 degrees with a maximum error of 0.7 mm.

This paper presents a comprehensive review on solar tracking systems and their potentials in solar energy applications. The paper overviews the design parameters, construction, types and drive system techniques covering different usage application. There are two main solar tracking systems types that depending on their movement degrees of freedoms are single axis solar tracking system and dual axis solar tracking system, which are addressed in the recent studies. The solar tracker drive systems encompassed five categories based on the tracking technologies, namely, active tracking, passive tracking, semi-passive tracking, manual tracking, and chronological tracking. The paper described the various designs and components of the tracking systems. There are 42.57% of the studies discussed and presented single axis tracking systems while 41.58% of these studies to the dual axes tracking systems. In the recent research studies, the most common solar tracker drive type was active tracker by 76.42% usage in applications while in the second most impact type is the chronological solar tracker by 7.55%. Furthermore, in the solar tracking techniques, Azimuth and altitude tracking achieved 16.67% in usage, Horizontal tracking by 16.67%, Azimuth tracking by 10%, and polar tracking by 4.44%.

Background The functional range of motion (fROM) of the metacarpophalangeal (MCP) joints during the performance of activities of daily living (ADL) has not yet been established. This study aimed to determine the fROM of all five digits and verify the accuracy and reproducibility of dynamic angle measurement using a single-axis electric goniometer (EG) during ADL movements of the hand. Methods This was a cross-sectional study. In EG suitability testing, we first confirmed the angles of a three-dimensional calibration device 10 times, and then compared EG readings with those determined by tomosynthesis images. Next, we determined the fROM of the MCP joints by evaluating all five digits of the dominant hands of 10 healthy adults performing 16 ADL. Intra-rater reproducibility of MCP joint data during task performance was assessed in two healthy adults. Results Static measurements of the triangular object showed variance to be within one degree in 39 of 40 trials. Differences between angles measured by the EG and those depicted by radiograph were a range of plus or minus five degrees in 88 of 96 digits. The fROM values for the thumb and index, middle, ring, and little fingers were −7.5 to 35.3, 10.6 to 67.8, 4.0 to 79.9, 3.0 to 83.9, and 2.9–91.4 degrees of flexion, respectively. Flexion angle in the fROM of the index finger was significantly smaller than those of the ring and little fingers. The flexion and extension angles of the thumb were significantly smaller than those of the four ulnar fingers. The intra-rater correlation coefficients of two participants were high at 0.94 and 0.93, respectively. Conclusions The method adopted in this study exhibited excellent accuracy and reproducibility and was therefore considered suitable for the real-time establishment of fROM flexion-extension angles of the MCP joints for all five digits. Our data are useful as a target arc of motion in the treatment of MCP joint disease or injury.

Objective: Human skin colour is influenced by three pigments: haemoglobin, carotenoids, and melanin. Carotenoids are abundant in fruits and vegetables, and when consumed accumulate in all layers of the skin, predominantly imparting yellowness (b*). This study investigated the effect of the manipulation of carotenoid-based skin colour, relative to the skin colour conferred by melanin on the perceptions of health amongst a group of Australian adults. Method: Fifty-seven participants (n = 4 male; mean age 27.9 ± 7.5 years) completed three computer-based experiments on 50 trial faces. In the first two experiments, face image colour was manipulated along one or two independent single carotenoid or melanin axes on each trial to ‘make the face appear as healthy as possible’. In the third trial, face colour was manipulated on both the carotenoid and melanin axes simultaneously. Results: For the single axis, participants significantly increased melanin colouration and added carotenoid colouration to facial images that were initially low in skin yellowness (b*). When carotenoid and melanin axes were simultaneously manipulated, carotenoid colouration was raised (ΔE = 3.15 ( SE ±0.19)) and melanin colouration was lowered (ΔE = −1.04 ( SE ±0.1)). Conclusions: Young Australian adults perceive facial skin colouration, associated with both carotenoid intake from fruit and vegetables and melanin due to sun exposure as conveying the appearance of health in young adults. However, carotenoid colouration was more important to health perception. Postprint

We and others recently developed rapid tilt-series acquisition methods for cryo-electron tomography on a Titan Krios G3i equipped with a single axis holder and a K-series direct electron detector and showed that one of these, the fast-incremental single exposure (FISE) method, significantly accelerates tilt-series acquisition when compared to traditional methods while preserving the quality of the images. Here, we characterize the behavior of our single axis holder in detail during a FISE experiment to optimally balance data quality with speed. We explain our methodology in detail so others can characterize their own stages, and conclude with recommendations for projects with different resolution goals.

Roundabouts became popular worldwide as a tool to reduce the number of car accidents and the EU encourages and promotes this technology as a solution to the problems of urban and extra-urban traffic. RAST (Roundabout Solar Tracking) systems are designed to exploit the available space in roundabouts, which are already equipped and monitored, in order to produce electricity with a photovoltaic single axis tracking system. The energy produced can be used directly by the surrounding facilities or stored and consumed later or channelled to nearby car charge points. The amount of energy that can be produced on a single roundabout is limited by the land size and is normally in the range 100-400 kWp, but the number of suitable roundabouts in cities is high. Therefore, RAST could make an important contribution to the energy production.

Varity of applications in science and engineering require technical abilities to conduct force measurements with high accuracy and precision in traceable manner. An example of such is the Lorentz Force Velocimetry (LFV), where forces of about 1 μN and below acting in horizontal direction on the object with approximately 1 kg weight are required to be resolved. In this paper we present a setup initially developed for this application, however, showing also a potential to be used elsewhere as a portable and conceptually unique setup. By the setup presented the force measurements in horizontal direction with 20 nN are resolved with 5 % to 7 % accuracy on the full range of the scale up to several mN.

In France, sweet cherry is generally trained in the now well-known vase training system. Growers know how to form and to prune trees in this system in order to have a good balance between yield and size of fruit. But in order to reduce production costs and to protect cherry fruit, other training systems that could be pruned mechanically and that allow installation of covers to protect against damage from rain or insects are being studied. A trial was planted in 2005 in order to compare agronomic and economic performances of three training systems using the scion cultivar 'Folfer(cov)': vase, single axis, and fruiting wall. Two rootstocks, Maxma® 14 and Tabel® Edabriz, were studied for the vase and fruiting wall systems, but only Tabel® Edabriz was used for the single axis. The cost to install the fruiting wall and single-axe systems is higher than the vase. However, the fruiting wall with Tabel® Edabriz exhibits greater precocity than the other training system/rootstock combinations. Fruiting wall with Tabel® Edabriz produces greater yields ha-1 with equal fruit quality. By contrast, sweet cherry on Maxma® 14 trained to the fruiting wall enters production later, and with lower yields than all other training system/rootstock combinations in this trial, such that after 8 years the cost of the plantation establishment had not yet been compensated with the production. Research findings regarding training system/rootstock combinations, yield, and fruit quality should be confirmed. Further, the question of long term performance must be studied.

That solar tracking improves energy yields from solar harvest systems is not debatable. Nor is the under powering of tropical Africa amidst plenty of energy resources – including solar. This paper presents a review of recent literature on tracking as applied to domestic solar harnessing devices. The purpose is to find basic requirements in design of a suitable solar tracker for the region’s rural homes. It is concluded that Single axis passive trackers possibly will stand better chances of acceptability in the region.

Incremental forming (IF), a novel sheet material forming technique which has the ability to eliminate the need for die sets, forms sheet material through the use of a non-cutting tool that gradually deforms the sheet material into the desired shape. Generally, the shape of the tool tip is a hemisphere. In the following works, the authors validate a novel tool shape, presented in Part 1 of this research, that allows forming of the sheet material in multiple directions at a rapid rate. The works described herein demonstrate that a more complex tool tip can result in greater formability, improved surface finish, and reduced springback. The tested tool tip shape described herein is that of two hemispherical tips, revolved about a common radius from a single axis, vertically offset to half of the tool path's step size.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Accelerated life testing has major impact on the success of a ground vehicle development program. Accelerated life testing profile should represent the customer usage so that optimum design can be achieved. A novel approach incorporating finite element analysis and vehicle durability test data into single axis accelerated life test profile generation was developed in this study. The proposed approach was successfully applied to the engine mount bracket of a heavy duty truck engine and it is validated by vehicle and rig tests. The accelerated life testing procedure developed in this study is applicable to many components of ground vehicles. It is possible to test components at high confidence level and low cost with this approach.

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The emergence of cost-competitive bifacial PV modules has raised the question of the additional value of bifacial 1-axis tracking arrays, in particular when considering rear-irradiance losses from the tracker system itself. In this work, the effect of different geometries and materials of torque tubes is evaluated through ray-trace simulations and found to cause rear irradiance shading factors between 2% to 8% for systems without gap between the modules in 2-UP configuration. Inclusion of a gap between the modules can offset the shading factor. Electrical mismatch is also evaluated for the various configurations, and a methodology to apply shading factor and electrical mismatch loss to rear irradiance from the calculated loss in DC power, which averages 1% for the systems explored here, is proposed.

A 25-MW solar power plant was commissioned in Andhra Pradesh, India in the first quarter of 2016. The 3 MW of single-axis tracker arrays co-located with 22 MW of fixed-tilt arrays provide a direct comparison of their performance under variable irradiance and thermal conditions to inform the cost-benefit analysis of future installations. Through March 2019, the single-axis tracker arrays have delivered an increase in energy yield of more than 14%.

Postural control can be improved with balance training. However, the nature and duration of the training required to enhance posture remains unclear. We studied the effects of 5 min of a self-initiated balance exercise along a single axis on postural control in healthy individuals. Postural control was measured before and after a 5-min period where members of the experimental group were asked to lean their entire body forward and backward and members of the control group were asked to remain seated. A significant improvement for sway velocity, a postural control variable significantly associated with an increased risk of falls, was found in the experimental group following the body sway exercise. These data suggest that a basic exercise can rapidly improve postural control and reduce the risk of falls.