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The safety performance of cooperative robots is particularly important. This paper aims to study collision detection and response of cooperative robots, which meet the lightweight requirements of cooperative robots and help to ensure the safety of humans and robots.

This paper proposes a collision detection, recognition and response method based on dynamic models. First, this paper identifies the dynamic model of the robot. Second, an external torque observer is established based on the model, and a dynamic threshold collision detection method is designed to reduce the interference of model uncertainty on collision detection. Finally, a collision position and direction estimation method is designed, and a robot collision response strategy is proposed to reduce the harm caused by collisions to humans.

Comparative experiments are conducted on static threshold and dynamic threshold collision detection, and the results showed that the static threshold only detected one collision while the dynamic threshold could detect all collisions. Conducting collision position and direction estimation and collision response experiments, and the results show that this method can determine the location and direction of collision occurrence, and enable the robot to achieve collision separation.

This paper designs a dynamic threshold collision detection method that does not require external sensors. Compared with static threshold collision detection methods, this method can significantly improve the sensitivity of collision detection. This paper also proposes a collision position direction estimation method and collision separation response strategy, which can enable robots to achieve post collision separation and improve the safety of cooperative robots.

The 3D dynamic clothing simulation is widely used in computer-added garment design. Collision detection and response are the essential component and also the efficiency bottleneck in the simulation. The purpose of this paper is to propose a high efficient collision detection algorithm for 3D clothing-human dynamic simulation to achieve both real-time and virtually real simulation effects.

The authors approach utilizes the offline data learning results to simplify the online collision detection complexity. The approach includes two stages. In the off-line stage, model triangles with most similar deformations are first, partitioned into several near-rigid-clusters. Clusters from the clothing model and the human model are matched as pairs according to the fact that they hold the potential to intersect. For each cluster, a hierarchical bounding box tree is then constructed. In the on-line stage, collision detection is checked and treated parallelly inside each cluster pairs. A multiple task allocation strategy is proposed in parallel computation to ensure efficiency.

Reasonably partitioning the 3D clothing and human model surfaces into several clusters and implementing collision detection on these cluster pairs can efficiently reduce the model primitive amounts that need be detected, consequently both improving the detection efficiency and remaining the simulation virtual effect.

The current methods only utilize the dynamic clothing-human status; the authors algorithm furthermore combines the intrinsic correspondence relationship between clothing and human clusters to efficiently shrink the detection query scope to accelerate the detection speed. Moreover, partitioning the model into several independent clusters as detection units is much more profitable for parallel computation than current methods those treat the model entirety as the unit.

Because of the high computational efficiency, response surface method (RSM) has been widely used in structural reliability analysis. However, for a highly nonlinear limit state function (LSF), the approximate accuracy of the failure probability mainly depends on the design point, and the result is that the response surface function composed of initial experimental points rarely fits the LSF exactly. The inaccurate design points usually cause some errors in the traditional RSM. The purpose of this paper is to present a hybrid method combining adaptive moving experimental points strategy and RSM, describing a new response surface using downhill simplex algorithm (DSA-RSM).

In DSA-RSM, the operation mechanism principle of the basic DSA, in which local descending vectors are automatically generated, was studied. Then, the search strategy of the basic DSA was changed and the RSM approximate model was reconstructed by combining the direct search advantage of DSA with the reliability mechanism of response surface analysis.

The computational power of the proposed method is demonstrated by solving four structural reliability problems, including the actual engineering problem of a car collision. Compared to specific structural reliability analysis methods, the approach of modified DSA interpolation response surface for structural reliability has a good convergent capability and computational accuracy.

This paper proposes a new RSM technology based on proxy model to complete the reliability analysis. The originality of this paper is to present an improved RSM that adjusts the position of the experimental points judiciously by using the DSA principle to make the fitted response surface closer to the actual limit state surface.

Reusability of geometric model is of essential importance in garment simulation since in reality, the same garment dressed on different human bodies will exhibit different draping results. Due to the multiplicity of a garment which can be dressed on various human bodies, it is necessary to reuse a given geometrical garment model in the cyberspace, the purpose of this paper is to explore this. This requires the technique of converting a geometrical model to a physically‐based model to predict the dressing result.

In this paper, a 3D garment model obtained from range data scanning is reconstructed as a mass‐spring system driven by the first order backward Euler integrator. The penetration of dressing onto the given avatars is compensated through an AABB accelerated collision detection and response scheme.

This paper implements efficient techniques resolving intersection for cloth simulation. Two stages are selected for handling the collision. The first stage is trying to prevent collision from happening in the first stage, and the second stage is to deal with actual intersections. This two‐stage approach eliminates almost all collision in the first stage, leaving only a few collisions for the second stage. Results obtained with this approach, in the case of dressing garments on different avatars are presented and validate the conversion method from geometric model to deformable one.

The experimental results validate this method as a useful and effective approach to exhibit draping behavior on various human body shapes accordingly.

Little is known regarding the impact of organizational policies and practices on police officers’ driving behaviors. To address an important gap in the empirical literature, this study examined how perceived likelihood of discipline for violations of agency driving policies impacted officer-involved vehicle collisions.

Surveys were distributed to patrol officers and their supervisors in eight California law enforcement agencies. The surveys elicited information regarding the perceived likelihood of discipline for violations of agency driving policies regarding cell phone use, text messaging, seatbelt use, speeding, and vehicle operations during emergency and pursuit situations.

The findings demonstrated a significant impact of perceived likelihood of enforcement for some but not all agency driving policies on officer-involved vehicle collisions.

This study was limited to self-reported data from patrol officers and their supervisors in eight California agencies.

Findings suggest that agencies may reduce officer injuries and other costs by increasing supervision and enforcement of agency driving policies.

This study contributes to the extant body of literature on officer-involved vehicle collisions by considering the impact of agency policy and supervision on officer behavior.

Aims to make an industrial robot work human‐friendly while coexisting with humans in a same working space, without any modification of the manipulator hardware as well as its motion controller.

Presents a weighted path planning approach based on collision detection for a robot sharing the same workspace with humans. Using a base and wrist force/torque sensors, a model‐based method is investigated to estimate the collision force and collision position on the manipulator; then a weighted path planning approach is developed to control the human‐robot interaction. Simulation experiments, with collisions between the manipulator and static objects and moving objects, are conducted to validate the efficacy of the method.

The experimental results illustrate the validity of the developed collision detection and planning scheme and make it possible for industrial robots to work safely around humans. The proposed weighted path planner (WPP) outperforms other three path planners.

Introduces the WPP based on collision detection. The wrist and base force/torque sensors configuration has the friction free benefit, and the developed method does not modify the existing designs of industrial robots. The contact force is well controlled under the human pain tolerance limit, through the modification of the desired path, and does not need torque control which is usually not available to industrial robots.

This paper aims to study the encounter issues of the Tethered-Space Net Robot System (TSNRS) with non-target objects on orbit during the maneuver, including the collision issues with small space debris and the obstacle avoidance from large obstacles.

For the collision of TSNRS with small debris, the available collision model of the tethered net and its limitation is discussed, and the collision detection method is improved. Then the dynamic response of TSNRS is studied and a closed-loop controller is designed. For the obstacle avoidance, the variable enveloping circle of the TSNRS has coupled with the artificial potential field (APF) method. In addition, the APF is improved with a local trajectory correction method to avoid the overbending segment of the trajectory.

The collision model coupled with the improved collision detection method solves the detection failure and speeds up calculation efficiency by 12 times. Collisions of TSNRS with small debris make the local thread stretch and deforms finally making the net a mess. The boundary of the disturbance is obtained by a series of collision tests, and the designed controller not only achieved the tracking control of the TSNRS but also suppressed the disturbance of the net.

This paper fills the gap in the research on the collision of the tethered net with small debris and makes the collision model more general and efficient by improving the collision detection method. And the coupled obstacle avoidance method makes the process of obstacle avoidance safer and smoother.

The work in this paper provides a reference for the on-orbit application of TSNRS in the active space debris removal mission.

Planning for collision avoidance is essential in any robot application, but for most single robot cells the ancillary equipment and tooling remain in fixed and known positions relative to the cell and thus collision avoidance strategies can be planned once only, at the start of program development. With multiple robot cells not only do the robots have to avoid the tools and furniture of the cell but also one another. The technology to allow robots to navigate around objects and select optimum paths is still not as cheap or reliable as would be required for use in standard manufacturing applications. Concludes that multiple robots in the same space can have many advantages and the technology exists to allow them to work together in an unsynchronized manner, checking for collisions before each movement, but that technology currently requires considerable effort on the part of robot users to develop and test their own software.

Critical social marketing can play a vital role in countering the consequences of behaviours toxified by commercial marketing. This paper aims to hypothesise that auto sector brand activities may be associated with riskier driving.

In this paper, the authors hypothesised that auto sector brand activities may be associated with riskier driving. UK collision data was examined, focusing on collisions that occurred because of an “injudicious action” (risky or aggressive driving manoeuvres) and analysing this data set by comparing the incidence of vehicle brands involved.

After allowing for other effects, a gradient graph illustrated differing associations between vehicle brands and collision rates.

A discussion was offered, adopting the position that if such a problem exists the solutions cannot be left to the sector itself, and that socially responsible interventions may be required. A number of social marketing strategies are proposed including regulatory support, “Truth Campaign” style exposure of commercial damage, and counter-marketing that promotes safe driver behaviour.

This work provides valuable empirical support to the concerns raised by previous workers about the possible effects of automotive sector advertising on driving behaviour. The paper offers a concise discussion of ways forward, concluding with the novel possibility of regulating individual brands as an alternative to sector-wide regulation.