Pushing Motion Research Articles

Development of a Bimanual Wearable Force Feedback Device with Pneumatic Artificial Muscles, MR Fluid Brakes, and Sensibility Evaluation Based on Pushing Motion

In a virtual reality (VR) space, wearing a head-mounted display can help with the visualization of objects; however, users cannot experience realistic tactile sensations. Recently, several force feedback devices have been developed, including wearable devices that use straight-fiber-type pneumatic muscles and magnetorheological fluids. This allows the devices to render elastic, frictional, and viscous forces during spatially unrestricted movement. Nevertheless, a problem remains in that previous devices could handle many bilateral upper limb movement tasks. Therefore, this study aims to develop a device that can handle movements that interact with both arms. Based on experiments concerning the pushing motion in a VR space, the influence of the pseudo force sense was determined to not be small. In addition, we confirmed that the force sensation presented by this system was more realistic when the robot was operated with both arms than when operated with the right arm.

Interactive 3D Force/Torque Parameter Acquisition and Correlation Identification during Primary Trocar Insertion in Laparoscopic Abdominal Surgery: 5 Cases.

Laparoscopic procedures have become indispensable in gastrointestinal surgery. As a minimally invasive process, it begins with primary trocar insertion. However, this step poses the threat of injuries to the gastrointestinal tract and blood vessels. As such, the comprehension of the insertion process is crucial to the development of robotic-assisted/automated surgeries. To sustain robotic development, this research aims to study the interactive force/torque (F/T) behavior between the trocar and the abdomen during the trocar insertion process. For force/torque (F/T) data acquisition, a trocar interfaced with a six-axis F/T sensor was used by surgeons for the insertion. The study was conducted during five abdominal hernia surgical cases in the Department of Surgery, Faculty of Medicine, Ramathibodi Hospital, Mahidol University. The real-time F/T data were further processed and analyzed. The fluctuation in the force/torque (F/T) parameter was significant, with peak force ranging from 16.83 N to 61.86 N and peak torque ranging from 0.552 Nm to 1.76 Nm. The force parameter was observed to positively correlate with procedural time, while torque was found to be negatively correlated. Although during the process a surgeon applied force and torque in multiple axes, for a robotic system, the push and turn motion in a single axis was observed to be sufficient. For minimal tissue damage in less procedural time, a system with low push force and high torque was observed to be advantageous. These understandings will eventually benefit the development of computer-assisted or robotics technology to improve the outcome of the primary trocar insertion procedure.

Learning Target-Oriented Push-Grasping Synergy in Clutter With Action Space Decoupling

We explore a method for grasping novel target objects through push-grasping synergy in a cluttered environment without using object detection and segmentation algorithms. The target information is represented by a color heightmap of the target object. The agent needs to implicitly find the corresponding object in the cluttered scene according to the target information and gives action instructions. We propose an action space decoupling framework to efficiently address the problem of policy learning in large state spaces, which predicts the grasping position and the grasping angle separately. Our system needs to learn two policy networks: position net and angle net. The position net infers the appropriate grasping position and the starting position of the pushing motion, and the angle net predicts the grasping angle based on the grasping position. In addition, the angle net is also a coordinator to determine whether the current state should perform the grasping action or the pushing action. A series of experiments show that the proposed method can quickly learn complex push-grasping coordinated policies in a cluttered environment and the task success rate and the grasping efficiency are greatly improved compared to the baseline methods and it has good generalization ability for novel objects. Furthermore, our method can be transferred to the real world without fine-tuning.

Flexible Sandwich-Structured Foldable Triboelectric Nanogenerator Based on Paper Substrate for Eco-Friendly Electronic Devices

Recently, as the use of wearable devices and the demand for eco-friendly energy have increased, many studies have been conducted on triboelectric nanogenerators (TENGs), which can economically harvest energy. Paper is considered a promising substrate and frame material that can be used to manufacture self-powered TENGs, owing to its flexibility, low cost, and accessibility. Herein, we present a sandwich-structured foldable paper-based TENG (FP-TENG) that comprises flexible materials and uses paper as a substrate. The FP-TENG can generate up to 572 mW/m2 of power via contact–separation of the triboelectric electrified body at the top and bottom. With more folds of the FP-TENG, the triboelectric cross-sectional area increases, and, thus, the electrical output increases. In addition, the proposed TENG exhibits excellent durability without signal degradation under 5000 cycles of repeated pushing motions. To demonstrate its practicality, the FP-TENG was manufactured in the form of a wristwatch Velcro and connected to an electronic watch panel to supply power. Various deformations are possible with origami, and they can drive wristwatches through external forces. Therefore, the FP-TENG is expected to be utilized as a sustainable and promising eco-friendly energy source for small electronic devices.

Electrical Energy Harvesting From Mechanical Motions by Employing Ferroelectrets Featuring Large Transverse Piezoelectric Activity

Fluorinated ethylene propylene (FEP) ferroelectret films with a parallel tunnel structure and significantly transverse piezoelectric effect are utilized to configurate energy harvesters for scavenging kinetic energy. In the device, a dual-steady cantilever beam structure is adopted to amplify the force input, and a stopper is used to control the strain of the film within an elastic deformation range. Results show that the maximum energy can be delivered to the storage capacitor being with the same capacitance of the device as theoretically predicted. For an energy harvester with an active area of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${30}\,\,\text {mm} \times {10}\,\,\text {mm}$ </tex-math></inline-formula> , the energy delivered to the storage capacitor is 23.5 nJ for one push motion with a displacement of 5.5 mm. The energy can be effectively enhanced by increasing the area of the ferroelectret film and multiplying devices in electrical parallel. These energy harvesters could be implemented in some facilities and devices, such as carpets, floors, and buttons, to scavenge the kinetic energy of motions at low frequencies.

Validity of the PUSH band 2.0 and Speed4lifts to measure velocity during upper and lower body free-weight resistance exercises

ABSTRACT Accuracy and test–retest reliability were assessed for two devices, PUSH Band 2.0 (PUSH) and Speed4lifts. Two identical sessions were performed 6–8 days apart. Twenty rugby league players performed three repetitions with 20%, 40%, 60% and 80% of estimated one repetition maximum for back squat (BS), front squat (FS), and bench press (BP). Velocity was recorded using PUSH, Speed4lifts and 3D motion analysis system (gold standard). Passing-Bablok regression analysis assessed agreement of velocity measures with the gold standard. Intraclass correlation coefficients (ICC) and coefficients of variation (CV) assessed test–retest reliability. PUSH and Speed4lifts were accurate for BS velocities <1.00 m/s and FS velocities <0.65 m/s. PUSH was accurate for BP velocities <0.65 m/s. Speed4lifts was accurate for BP velocities between 0.65–1.00 m/s. PUSH was reliable at all loads (ICC = 0.79–0.92; CV = 2.63–6.89%) except for 20% FS and BP (ICC = 0.49–0.64; CV = 3.13–3.62%). Speed4lifts was reliable at all loads (ICC = 0.70–0.96; CV = 2.57–4.26%) except for 20% BP (ICC = 0.59; CV = 4.59%). These results suggest that both devices are unsuitable for measuring the velocity of BS, FS and BP at faster velocities and at lighter loads.

Effect of hand loads on upper extremity muscle activity during pushing and pulling motions

Manual pushing or pulling with a hand tool is a coordinated action by various upper extremity muscles. The objective of this experimental study was to examine the effects of horizontal and vertical hand loads on upper extremity muscle activity during concentric pushing and pulling exertions. Twenty young female participants conducted repetitive pushing and pulling trials with three horizontal loads (1 kg, 2 kg, 3 kg) and two vertical loads (0.6 kg, 1.3 kg) in a seated posture, while the myoelectric activity of seven upper extremity and shoulder muscles were quantified. Study results indicate that the shoulder flexor and extensor muscles were more strongly associated with horizontal load, and elbow flexors were more sensitive to vertical load. The empirical data from this systematic evaluation can offer initial insights for ergonomic design and evaluation of hand tools or occupational tasks that involve repetitive pushing or pulling.

Hand Gesture Detection and Recognition Using Spectrogram and Image Processing Technique with a Single Pair of Ultrasonic Transducers

This paper presents an effective signal processing scheme of hand gesture recognition with a superior accuracy rate of judging identical and dissimilar hand gestures. This scheme is implemented with the air sonar possessing a pair of cost-effective ultrasonic emitter and receiver along with signal processing circuitry. Through the circuitry, the Doppler signals of hand gestures are obtained and processed with the developed algorithm for recognition. Four different hand gestures of push motion, wrist motion from flexion to extension, pinch out, and hand rotation are investigated. To judge the starting time of hand gesture occurrence, the technique based on continuous short-period analysis is proposed. It could identify the starting time of the hand gesture with small-scale motion and avoid faulty judgment while no hand in front of the sonar. Fusing the short-time Fourier transform spectrogram of hand gesture to the image processing techniques of corner feature detection, feature descriptors, and Hamming-distance matching are the first-time, to our knowledge, employed to recognize hand gestures. The results show that the number of matching points is an effective parameter for classifying hand gestures. Based on the experimental data, the proposed scheme could achieve an accuracy rate of 99.8% for the hand gesture recognition.

Resurfacing processes on asteroid (162173) Ryugu caused by an artificial impact of Hayabusa2's Small Carry-on Impactor

The resurfacing process on Ryugu accompanying the artificial impact crater formation by Hayabusa2's Small Carry-on Impactor (SCI) was studied by comparing pre- and post-impact images of this region captured by an optical navigation camera. Three different aspects of the resurfacing process were examined: the crater rim profiles, the motion of boulders and the appearance of new boulders, and the motion vectors of Ryugu's surface around the SCI crater. The averaged crater rim height, h, was derived as follows: h = hr exp [−(r/Rrim − 1)/λrim], where Rrim is the SCI crater rim radius of 8.8 m, the fitted parameter, hr, is 0.475 m, and the λrim is 0.245. The ejecta blanket thickness of the SCI crater was thinner than that estimated from both the observation of natural craters and the crater formation theory. However, this discrepancy of the ejecta blanket thickness was resolved by taking into account the new boulders appearing in the post-impact images in the volume. The motion of the discovered boulders could be classified by its mechanisms as follows: a dragging motion created by excavation flow during the crater formation, a pushing motion created by falling-back ejecta, a dragging motion created by the slight motion of the Okamoto boulder, and a motion caused by seismic shaking induced by the SCI impact itself. The seismic shaking caused boulders to move farther than 3 cm from the original site in most of the region within 15 m distance from the SCI crater center, where the maximum acceleration of the impact induced seismic waves 7 times larger than the surface gravity of Ryugu based on the laboratory experiments (Matsue et al. [2020] Icarus, 338, 113520), and the evidence of the seismic shaking for boulders with a movement of >3 cm was detected in about 10% of the boulders in the region between 15 m and 30 m from the crater center, which region was inferred to experience acceleration larger than the Ryugu's surface gravity based on previous laboratory experiments (Matsue et al. [2020] Icarus, 338, 113520).

A Case Study on Curling Stone and Sweeping Effect According to Sweeping Conditions.

The purpose of this study was to use the same ice temperature and air temperature as the Pyeongchang Curling Stadium by using an Ice Chamber. Then, launch the stone at the same speed, and move according to the sweeping conditions (perpendicular to the axis of motion, along the axis of motion) of male and female elite curlers. The aim is to provide sports science information required for curling athletes by analyzing the distance of the stone, the change in the speed of a moved stone, the change in broom acceleration, and athletes’ muscle activity. The results of experiments conducted on four male and four elite female curlers are as follows. Under gender, the stone’s movement distance was long after the sweeping of male athletes, and the speed of the stone was not different according to the conditions. The broom’s acceleration did not show a difference in both the sweeping condition and the athlete’s gender condition, and the muscle activity did not show a significant difference in both the sweeping condition and the gender condition. In summary, it is thought that male athletes moved the stone farther by raising the ice surface temperature by vertical load than female athletes. Also, there was no statistically significant difference in muscle activity results, but it was found that there was a specific pattern of muscle activity in the pushing and pulling motions during the sweeping of male and female athletes. It is expected to be used as primary data.

InSAR 3-D Coseismic Displacement Field of the 2015 Mw 7.8 Nepal Earthquake: Insights into Complex Fault Kinematics during the Event

The 2015 Mw 7.8 Gorkha, Nepal, earthquake occurred in the central Himalayan collisional orogenic belt, which demonstrated complex fault kinematics and significant surface deformation. The coseismic deformation has been well documented by previous studies using Global Positioning System (GPS) and Interferometric Synthetic Aperture Radar (InSAR) data. However, due to some limitations of spatially sparse GPS stations and InSAR only-one-dimensional observation in the line-of-sight (LOS) direction, the complete distribution and detailed spatial variation of the three-dimensional surface deformation field are still not fully understood. In this study, we reconstructed the three-dimensional coseismic deformation fields using multi-view InSAR observations and investigated the refined surface deformation characteristics during this event. We firstly obtained four ascending and descending InSAR coseismic deformation maps from both Sentinel-1A/B and ALOS-2 data. Secondly, we obtained the synthetic north-south deformation field from our best-fitting slip distribution inversions. Finally, we calculated three-dimensional deformation fields, which were consistent with coseismic GPS displacements but with higher resolution. We found that the surface deformation is dominated by horizontal southward motion and vertical uplift and subsidence, with minor east-west deformation. In the north-south direction, the whole deformation area reaches at least 150 × 150 km with a maximum displacement of ~1.5 m. In the vertical direction, two areas, including uplift in the south and subsidence in the north, are mapped with a peak displacement of 1.5 and −1.0 m, respectively. East-west deformation presented a four-quadrant distribution with a maximum displacement of ~0.6 m. Complex thrusting movement occurred on the seismogenic fault; overall, there was southward push motion and wave-shaped fold motion.

An obstacle separation method for robotic picking of fruits in clusters

Selectively picking a target fruit surrounded by obstacles is one of the major challenges for fruit harvesting robots. Different from traditional obstacle avoidance methods, this paper presents an active obstacle separation strategy that combines push and drag motions based on 3D visual perception to separate obstacles from the target. We define a region of interest 3D point cloud with a number of sub-blocks around the target to determine the presence or absence of obstacles and generate the separation paths accordingly. A linear push is used to clear the obstacles from the area below the target, while a zig-zag push that contains several linear motions is proposed to push aside more dense obstacles. The zig-zag push can generate multi-directional pushes and the side-to-side motion can break the static contact force between the target and obstacles, thus helping the gripper to receive a target in more complex situations. Moreover, we propose a novel drag operation to address the issue of mis-capturing obstacles located above the target, in which the gripper drags the target to a place with fewer obstacles and then pushes back to move the obstacles aside for further detachment. Furthermore, an image processing pipeline consisting of color thresholding, object detection using deep learning and point cloud operation, is developed to implement the proposed method on a newly developed harvesting robot. Field tests show that the proposed method can improve the picking performance substantially. This method helps to enable complex clusters of fruits to be harvested with a higher success rate than conventional methods.

A preliminary muscle activity analysis: Handle based and push-rim wheelchair propulsion

Approximately ninety percent of the wheelchair users worldwide prefer the conventional push rim mode of propulsion for daily mobility and rehabilitation. Even though push-rim wheelchairs help to promote a healthy life style, the high muscular demand and the non-continuous push motions can lead to serious upper extremity injuries. In this study, muscle EMG data of ten healthy subjects were recorded for a newly introduced handle based propulsion mechanism (HBP) and compared to conventional push-rim propulsion at two workloads, 25 W and 35 W respectively. The results for the mean peak muscle activations at both workloads demonstrate that push-rim propulsion leads to higher peak muscle activity compared to HBP at a similar wheelchair forward velocity of 1.11 m/s. The generation of these high peak muscle activations with increasing loads in push-rim propulsion over time can lead to overuse injuries. Overall, the use of the HBP mechanism is less straining to the muscles and may reduce fatigue during prolonged propulsion.

Ergonomics as a Social Component of Sustainable Lot-sizing: A Review

Lot-sizing has an increased attention in recent years. In the area of production planning and control, this trend has given rise to the development of lot-sizing models that considers sustainability issues besides the optimization of total operational cost. The study is based on tertiary study that is ensured to analyze the total work have been published. The research was conducted by the definition of appropriate keywords for understanding sustainability issues and ergonomics as a social component in lot-sizing. The paper at hand attempts to understand the development of sustainability issues in lot-sizing and ergonomics as a social component in lot-sizing. We observe that studies focusing on all three dimensions of sustainability are comparatively scarce. However, only a few of the studies have been covered the social sustainability aspect. It is observed that studies addressing ergonomics issues are scarce, and more focus is required on the social sustainability impacts along the supply chain and lot-sizing. Most of ergonomic assessment covered relaxation allowance and energy expenditure rate, OWAS, NIOSH and another consideration about ergonomic lot-sizing is the motion types investigated by authors which were picking, storing as a lifting and carrying motions and did not covered pushing, pulling, bending and other hand motions which have positive relationship with work related musculoskeletal disorders. Finally, we propose future directions to extend research on the ergonomics in lot-sizing.

Problems of dynamometer construction for wheelchairs and simulation of push motion

The article discusses the problem of the construction of a test stand that allows simulation of wheelchair propulsion in various terrain conditions. The described test stand is a complete measuring system which allowing to analyse the parameters of the biomechanical system human-wheelchair. The described test stand allows observation of biomechanical parameters such as: centre of gravity, muscle activity, path, speed and acceleration. An important aspect of test stand is to replicate the real wheelchair motion in to laboratory conditions. The effect of the considerations taken in the article is the development of the structure, the construction of the test stand and the development of a research method using the stand.

Snap-through under unilateral displacement control with constant velocity

When the side of a beverage can or the domed lid of a jar is pushed inward, all or part of the structure may suddenly snap into an inverted configuration. The velocity of the pushing motion affects this instability. Most previous analyses of snap-through have considered force control (increasing the pushing force, e.g., a weight). Snap-through under dynamic, unilateral displacement control is investigated here, with the indentor moving at constant velocity (as in a universal testing machine) until snap-through occurs. Shallow elastic arches with immovable pinned ends are analyzed. Attention is focused on the critical height of the indentor at which snap-through is initiated. The effects of the indentor velocity, indentor location along the span, initial arch height, and damping magnitude are investigated. In addition, experiments are conducted on shallow buckled beams, which behave similarly to arches. Usually, the higher the indentor velocity, the further the indentor must move before snap-through occurs.

Ergonomics of Prehensility in Pushing and Pulling Motions: An Anatomical and Biomechanical Overview

The hand represents one of the most remarkable expressions of humanization of the anterior limb. The anterior limb, at first ambulatory, underwent continuous evolution acquiring innumerable new functions. In the course of human evolution the hand has undergone continual structural and functional adaptations, characterized, among others, by enrichment of peripheral innervation and further development of the thumb. This development was accompanied by important changes in the brain and the relocation of the eyes, together allowing the muscle control and stereoscopic vision, necessary for a controlled grip. The anatomy of the hand is complex, intricate, and fascinating. Its integrity is absolutely essential for our everyday functional living. It is intimately correlated with the brain, both in the evolution of the species and in the development of the individual. Actually, we can state that we “think” and “feel” with our hands, hence, their contribution is essential to the mental processes of thought and feeling. The aim of this review is to evaluate the most typical hand quality, the prehensility and hence, the possibility of manoeuvring tools. Our attention is mainly focused on the hand anatomy and prehensility during pushing and pulling motions. In particular, our attention is directed toward the relationship existing between the hand prehensility and the volume of the object to be gripped. As an example, we use a grip of the paddle and, pushing and pulling motions during kayak paddling. Indeed, we are firmly convinced that the prehensility plays a crucial role not only in performing the stylistically correct paddling, but especially in realizing a more effective and powerful paddle stroke. This review highlights a great link existing between biomechanical and anatomical notions and sporting performance.

Laser pushing or pulling of absorbing airborne particles

A single absorbing particle formed by carbon nanotubes in the size range of 10–50 μm is trapped in air by a laser trapping beam and concurrently illuminated by another laser manipulating beam. When the trapping beam is terminated, the movement of the particle controlled by the manipulating beam is investigated. We report our observations of light-controlled pushing and pulling motions. We show that the movement direction has little relationship with the particle size and manipulating beam's parameters but is dominated by the particle's orientation and morphology. With this observation, the controllable optical manipulation is now able to be generalized to arbitrary particles, including irregularly shaped absorbing particles that are shown in this work.

Evaluating both Physiological and Biomechanical Strains in Women Using Different Hoe Handle Designs

Physiological and biomechanical strains were investigated in women using four different handle designs for hoe. Electromyography (EMG), energy expenditure, and task workload were measured while using four different hoes: a conventional hoe with 1) the normal (N) handle, 2) the second (S) handle, 3) the T-grip with arm supporter (TA) handle, and 4) the second with T-grip and arm supporter (STA) handle. Each handle strained different regions of the body. The S handle was significantly better for minimizing the erector spinae muscle EMG. The TA handle required less effort on the flexor digitorum profundus (FDP), but more effort on the posterior deltoid. From the STA handle, no interaction was found between the S and TA handle. The results from energy expenditure analysis indicated that the workload in hoeing involves mainly a pushing and pulling motion of the shoulder (r = .923). In comparison with the N handle, the additional handles caused a significantly greater workload, but there was no significant difference between those three handles.

押し動作における自他身体誘導スキルの計測と解析

Humanoid robots should be able to handle independently human bodies. In previous studies, robots manipulated human bodies using brute force, but this does not accurately reflect a human's action. Yoshinori Kouno, who has studied several skills related to physical exertion, including martial arts and nursing-care motions possesses, as the subject, we studied these motions and analyzed the techniques that were superior to other body dynamics. In this study, we focused on the pushing action of human, and aimed to understand the body's dynamics. The zero moment point (ZMP) trajectories of the actor varied around the center of gravity (COG), and the actor used the falling momentum to push the recipient's body. Kouno reported that the position of the fingers enabled him to control his arm movements. Hence we analyzed the electromyogram signals of the whole body. Analysis of the recipient's resistance based on the ZMP and COG, suggests that the recipient can predict the attack by the actor of the action and braces him/herself for the impact. Thus, the actor needs to confound the recipient's prediction to realize human pushing motions with less effort. The falling momentum strategy and change in the arm's force play an important role to in confusing the prediction. We confirm the effectiveness of these body dynamics using numerical simulation. Finally, we conclude that the “knack” of the pushing motion is due to a special pose of fingers.