基于压力分布实验的汽车座椅人机形态研究

目的根据人机工程理论及人体的生理学特征,结合汽车座椅坐垫和靠背的人机形态指标,探讨座椅造型设计与人机形态之间的对应规律。方法压力实验采用VERSION Tekscan压力测量系统7.60-21C和CONFORMat Research软件对压力分布数据进行采集和处理。共选取6名被试者,分别对三款座椅进行乘坐实验,并结合问卷访谈的调查进行对比分析。结果实验统计得出每款座椅靠背与坐垫部分的接触面面积、平均压强、峰值压强等值,进一步数据挖掘,显示出符合人机形态的新型汽车座椅在舒适性方面明显优势。结论人机形态对于汽车座椅的舒适性有着至关重要的影响。

基于压痛耐受力的手柄接触面人机形态设计

为使手柄接触面形态设计具有更好的生理学和力学基础,从而提高手柄的人机性能,从人体疼痛感知特性出发,在模拟实验室中对160名受测者进行手掌压痛耐受力实验。将压痛耐受力数据作为外载荷,采用能量优化模型对手柄接触面人机形态进行初步设计并获得标准静态曲面,采用骨粒串主导的曲面变形技术和Dexmo手部动作捕捉设备,对标准静态曲面进行变形并完善手柄形态设计方案。实验和评价结果表明,新方案比传统提手手柄具有更大的工作接触面积和更高的主客观舒适性,显著提高了人在工作时的单手提力。

Inchworm locomotion gait for snakelike robot

To establish a universal and easily controlled gait for practical use of snakelike robot movement, an inchworm locomotion gait model based on a serpenoid curve is presented. By analyzing the relations of two adjacent waves in the process of locomotion and doing an approximation of the serpenoid curve, the motion function of relative angles between two adjacent links and the absolute angles between each link and the baseline on the traveling curve are built. Two efficiency criterions of the gait are given as the energy loss function f and the unit displacement in one cycle dunit.Three parameters of the criterions affecting the efficiency of the gait （ the number of links that form the traveling wave n, the included angle between two adjacent links α, and the phase difference of adjacent included angles β） are discussed by simulations and experiments. The results show that f is insensitive to n; raising n increases dunit significantly; the maximum wave amplitude of α is a decreasing function of n; and increasing α reduces the displacement influence off when n is determined. The gait model is suitable for different inchworm locomotions of a snakelike robot whose traveling waves are formed by different numbers of identical links. A wave formed by more links or a greater relative angle between two adjacent links both lead to greater velocity of the movement.

DARPA Robotics Grand Challenge Participation and Ski-Type Gait for Rough-Terrain Walking

In this paper, we briefly introduce the history of the Defense Advanced Research Projects Agency(DARPA) Grand Challenge programs with particular focus on the 2012 Robotics Challenge. As members of team DRC-HUBO, we propose different approaches for the Rough-Terrain task, such as enlarged foot pedals and a transformation into quadruped walking. We also introduce a new gait for humanoid robot locomotion to improve stability performance, called the Ski-Type gait. We analyze the stability performance of this gait and use the stability margin to choose between two candidate step sequences, Crawl-1 and Crawl-2. Next, we perform a force/torque analysis for the redundant closedchain system in the Ski-Type gait, and determine the joint torques by minimizing the total energy consumption. Based on the stability and force/torque analysis, we design a cane length to support a feasible and stable Crawl-2 gait on the HUBO2 humanoid robot platform. Finally, we compare our experimental results with biped walking to validate the SkiType gait. We also present our team performance in the trials of the Robotics Challenge.

Hybrid input shaping control scheme for reducing vibration of robot based on multi-mode control

The classic multi-mode input shapers(MMISs)are valid to decrease multi-mode residual vibration of manipulators or robots simultaneously.But these input shapers cannot suppress more residual vibration with a quick response time when the frequency bandwidth of each mode vibration is very different.The methodologies and various types of multi-mode classic and hybrid input shaping control schemes with positive impulses were introduced in this paper.Six types of two-mode hybrid input shapers with positive impulses of a 3 degree of freedom robot were established.The ability and robustness of these two-mode hybrid input shapers to suppress residual vibration were analyzed by vibration response curve and sensitivity curve via numerical simulation.The response time of the zero vibration-zero vibration and derivative(ZV-ZVD)input shaper is the fastest,but the robustness is the least.The robustness of the zero vibration and derivative-extra insensitive(ZVD-EI)input shaper is the best,while the response time is the longest.According to the frequency bandwidth at each mode and required system response time,the most appropriate multi-mode hybrid input shaper(MMHIS)can be selected in order to improve response time as much as possible under the condition of suppressing more residual vibration.

Metamorphic strategy based on dynamic meta-modules for a self-reconfigurable robot

For a self-reconfigurable robot, how to metamorphose to adapt itself to environment is a difficult problem. To solve this problem, a new relative orientation model which describes modules and their surrounding grids was given, a module motion rules database which enables the robot to avoid obstacles was established, and finally a three-layer planner based on dynamic meta-modules was developed. The firstlayer planner designates the category of each module in robot by evaluation functions and picks out the modules in dynamic meta-modules. The second-layer planner plans the dynamic meta-module path according to output parameters of the first-layer planner. The third-layer planner plans the motion of the modules in dynamic meta-module using topology variation oriented methods. To validate the efficiency of the three-layer planner, two simulations were given. One is the simulation of a single dynamic meta-module, the other is the simulation of planning with an initial configuration composed of 8 modules in complicated environment. Results show that the methods can make robot with any initial configuration move through metamorphosis in complicated environment efficiently.

Dynamic formation control for autonomous underwater vehicles

Path planning and formation structure forming are two of the most important problems for autonomous underwater vehicles(AUVs) to collaborate with each other.In this work,a dynamic formation model was proposed,in which several algorithms were developed for the complex underwater environment.Dimension changeable particle swarm algorithm was used to find an optimized path by dynamically adjusting the number and the distribution of the path nodes.Position relationship based obstacle avoidance algorithm was designed to detour along the edges of obstacles.Virtual potential point based formation-keeping algorithm was employed by incorporating dynamic strategies which were decided by the current states of the formation.The virtual potential point was used to keep the formation structure when the AUV or the formation was deviated.Simulation results show that an optimal path can be dynamically planned with fewer path nodes and smaller fitness,even with a concave obstacle.It has been also proven that different formation-keeping strategies can be adaptively selected and the formation can change its structure in a narrow area and restore back after passing the obstacle.

The HITCR-I:Evaluation on a free gait generation method for the hexapod robot on irregular terrain

The purpose of this paper is to present and evaluate a method of free gait generation for HITCRI,a hexapod walking robot.The HITCR-I is designed as a modularized structure of legs that is based upon a four-bar linkage mechanism and with force sensors in the tip of legs,distributed hardware structure and a modular software structure of the control system.Based on a set of local rules between adjacent legs,finite state machine(FSM) model is built to control the coordination of legs.An automatic smooth transition of gait pattern is achieved through deriving the mathematical relation between gait pattern and locomotion parameters.The disordered inter-leg phase sequence is adjusted to a regular state smoothly and quickly by the local rules based FSM,and the gait pattern can transform automatically adapting to irregular terrain.The experiment on HITCR-I has demonstrated that it can walk through irregular terrain reliably and expeditiously with the free gait controller designed in this paper.

Use of Context Blocks in Genetic Programming for Evolution of Robot Morphology

The paper explores applications of genetic programming to co-evolution of morphology and low-level control. In most reasonably difficult tasks, facilitation provided by modularity has proved to be vital for successful application of genetic programming. However, the need for sharing data among nodes in the syntactic tree becomes especially acute when evolving modular programs. It has been shown before that it may be beneficial that modules themselves be node-attached. The paper presents extensions to standard genetic programming （the so-called contexts and context blocks） that allow for straight-forward storage, retrieval, transfer, and modification of data stored in the context of a syntactic tree, and shared by multiple nodes. Framework is thus provided for both： data sharing and node-attached modules. Finally, using context blocks, a genetic algorithm has been embedded within genetic programming to evolve values of constants. In genetic programming evolution of constants has been a long-standing problem. The paper shows how context blocks can be utilized to provide a more granular and flexible approach to their evolution. As shown in previous works, node-attached modules perform favorably when compared with existing approaches. Concerning evolution of context block constants, it is shown here that they too perform favorably when compared with ephemeral constants.

Gait fitting for snake robots with binary actuators

Thanks to the special physical architectures and various locomotion gaits,snake robots may offer significant benefits over traditional legged or wheeled locomotion designs in vast types of scenarios.This paper proposes an innovative snake robot with digitally-actuated Stewart platforms as its modules and mainly focuses on the simulations of various snake gaits.Three categories of fitting algorithms are elaborated in simulations of lateral undulation and Configuration-Fitting Algorithm of Four Modules is demonstrated as a universal gait fitting algorithm for all kinds of snake robots with binary actuators.Several typical snake gaits are simulated and the results demonstrate the excellent mobility of the snake robot.