Passive Dynamic Walking Research Articles

2A2-G08 教育のための段ボール紙を用いた三次元受動歩行機製作方法について(ロボコンを通した教育)

2A2-G08 教育のための段ボール紙を用いた三次元受動歩行機製作方法について(ロボコンを通した教育)

Performance comparison of a planar bipedal robot with rigid and compliant legs

AbstractThe purpose of this work is to study the effect of placing passive storage elements (springs) along the robot legs on its performance. We first present the model of a planar passive dynamic walker with compliant ground contact model, then replace its rigid legs with compliant legs. Simulation results validate the effectiveness of compliant legs in improving the performance (robustness and velocity) of the robot.

2P1-E07 受動歩行の安定足形状を用いた歩行安定化補助靴の開発(福祉ロボティクス・メカトロニクス(1))

2P1-E07 受動歩行の安定足形状を用いた歩行安定化補助靴の開発(福祉ロボティクス・メカトロニクス(1))

2A2-Q11 受動歩行理論の中学校技術教育への応用(受動歩行ロボット)

2A2-Q11 受動歩行理論の中学校技術教育への応用(受動歩行ロボット)

On Internal Stabilizing Mechanism of Passive Dynamic Walking

In this paper, the relationship between the internal stabilizing mechanism of passive dynamic walking and linear optimal control is investigated. In contrast to existing results, it is shown that t...

D12 上半身を有する準受動的二足歩行ロボットの製作と解析(D1ロボット制御)

D12 上半身を有する準受動的二足歩行ロボットの製作と解析(D1ロボット制御)

2A2-Q01 連結型リムレスホイールにおける位相差の調節による高速化の実験的検証(受動歩行ロボット)

This paper investigates efficiency of passive dynamic walking of a combined rimless wheel (CRW) that consists of two identical 8-legged rimless wheels. We derive the mathematical equations of the CRW and conduct numerical simulations to examine that a stable passive gait can be generated in the presence of the phase difference between fore and hind legs. We then numerically show that the phase difference improves the gait efficiency in terms of walking speed, and discuss the inherent speeding-up mechanism from the potential barrier point of view. Furthermore, the validity of the derived results is evaluated by using an experimental machine.

High-speed and energy-efficient biped locomotion based on Virtual Slope Walking

In our previous work, we have presented results on Virtual Slope Walking, that is when a robot walks on level ground down a virtual slope by leg length modulation, based on the potential energy restoration in Passive Dynamic Walking. In this paper, we introduce the model of Virtual Slope Walking with Trajectory Leg Extension (TLE) and equivalent Instantaneous Leg Extension (ILE) under the Equivalent Definition. The analytic solution of the model's fixed point is obtained to analyze the essence of Virtual Slope Walking. We systematically investigate the characteristics and illustrate the effect of model parameters: the length-shortening ratio β, the equivalent extension angle $\theta^{*}_{\mathrm{II}}$ , and the inter-leg angle ? 0. We examine the energy efficiency and walking speed to demonstrate that Virtual Slope Walking is effective in generating high speed and energy-efficient walking. The high energy efficiency of the proposed model is theoretically confirmed. And the fast walking is validated by the experiments of a planar biped robot Stepper-2D, which achieves a sufficiently fast relative speed of 4.48 leg/s.

Optimized Configuration for the Upper Body with a Bisecting Hip Mechanism in Passive Dynamic Walking

Biped passive dynamic walking is a promising idea towards the goal of humanoid robotics further after the proposal of the upper body in these years. In this paper, we deduce the dynamic robot model with the upper body based on bisecting hip, in which the section of the swing phase is performed by Lagrange method, while the section of the collision phase is completed in terms of the principle of angular momentum conservation. The analysis of the global stability and the local stability are combined with each other, based on which the configurations of parameters with different mass and size of the upper body are discussed. Finally the optimized configuration of the model is obtained after the simulation in Adams environment. Results verify that the model with an upper body exhibits an extraordinary stability and robustness under circumstances of either a single disturbance or random disturbances.

Estimation of the Stable Fixed Point of Passive Dynamic Walking with BP Neural Network

The dynamic model of passive dynamic walking robot is given.BP(backpropagation) neural network(NN) is used to estimate the stable fixed point,and the estimated fixed point is taken as initial value for Newton-Raphson iteration to search the stable fixed point.This method solves the problems of low successful search rate and long search time caused by the improper initial value for the walking model which is not the simplest in previous study.Small variation of parameters leads to small variation of fixed points when acquiring training samples.When calculating fixed points of two successive samples,only one parameter has a small variation.The fixed point obtained with Newton-Raphson iteration is used as initial value for the next sample.1000 groups of parameters are generated randomly to test the NN performance.The results show that this method increases the successful search rate of stable fixed points significantly and shortens the search time greatly.

Outdoor Environments Walking by Biped Passive Dynamic Walker with Constraint Mechanism

This paper verified the stability of passive dynamic bipedal walking indoors and outdoors using a foot shape enhancing walking stability and implementing control constraint. Outdoor walking is difficult for walkers due to the unpredictable aspects of loose slopes, bumpy surfaces, and uneven friction on roads.

EFFECTS OF FOOT SHAPE ON ENERGETIC EFFICIENCY AND DYNAMIC STABILITY OF PASSIVE DYNAMIC BIPED WITH UPPER BODY

Passive dynamic walking has been developed as a possible explanation for the efficiency of the human gait. In this paper, we investigate the effects of foot shape on energetic efficiency and dynamic stability of passivity-based bipeds with upper body. Three walking models with point feet, round feet and flat feet were presented. Each model has an upper body constrained to keep midway between legs. We use computer simulations to find which foot shapes are indeed optimal in view of energetic efficiency and dynamic stability for a passive dynamic biped with upper body. Simulation results indicate that feet improve both the energetic efficiency and dynamic stability of passive dynamic bipeds.

Efficient dynamic bipedal walking using effects of semicircular feet

SUMMARYAchieving energy-efficient and high-speed dynamic walking has become one of the main subjects of research in the area of robotic biped locomotion, and passive dynamic walking has attracted a great deal of attention as a solution to this. It is empirically known that the convex curve of the foot, which characterizes passive–dynamic walkers, has an important effect on increasing the walking speed.This paper mainly discusses our investigations into the driving mechanism for compass-like biped robots and the rolling effect of semicircular feet. We first analyze the mechanism for a planar fully actuated compass-like biped model to clarify the importance of ankle-joint torque by introducing a generalized virtual-gravity concept. A planar underactuated biped model with semicircular feet is then introduced and we demonstrate that virtual passive dynamic walking only by hip-joint torque can be accomplished based on the rolling effect. We then compare the rolling effect with a flat feet model through linear approximation, and show that the rolling effect is equivalent to virtual ankle-joint torque. Throughout this paper, we provide novel insights into how zero-moment-point-free robots can generate a dynamic bipedal gait.

EFFECTS OF RAMP ANGLE AND MASS DISTRIBUTIONS ON PASSIVE DYNAMIC GAIT — AN EXPERIMENTAL STUDY

A bipedal walking mechanism with knees is designed and built to study the passive dynamic gait. The effects of changing the ramp angle and the mass distributions of the thighs and the shanks on the gait patterns and walking robustness are studied. It is shown that the changes in the ramp angle and the mass distribution have significant effects on the step lengths and the robustness (the successful rate of launching and the step-count) of the passive gait. More specifically, as the ramp angle increases or the mass center of the entire walker is raised, the step length increases, which dictates the walking speed. However, our experiments show that the changes in the ramp angle and the mass distribution have slight effects on the step period. The optimal ramp angle and mass distribution of the passive walker are also identified, of which the passive walker has the highest successful rate of launching and the step-count. Our experimental results are compared with previous work based on simulations. This research can provide important information for validating/adjusting mathematical models of passive dynamic walking. The work also enables us to gain a better understanding of the mechanics of walking.

2A2-E20 受動的動歩行の原理を利用した脚式歩行ロボットの開発

It is well-known that Passive dynamic walking robots walk efficiently, however, the robots are not able to walk on the level ground. Therefore we try to develop a semi-passive dynamic walking robot which can walk on the level ground by adding torques of ankle region using the property of Passive dynamic walking. In this paper we report a simulation result which indicates semi-passive dynamic walking realization.

2A2-E22 受動歩行と人間の歩行運動のスペクトル解析

Passive dynamic walk is nearly human walk, because passive dynamic walk use the energy that is only gravity field. This research used kinematic analysis for identifying similarities and differences human walk and passive dynamic walk. As a motion analysis, we compared the trajectory that was calculated the ground reaction force from the center of gravity of human walking and stable biped passive dynamic walking. This paper reported about the result of spectral analysis of the trajectory of the center of the gravity by walking of human and passive dynamic walker.

2A1-E07 乗用二足歩行BiTrekkerの研究 : 基本構造と試作・試乗・シミュレーション

In this paper, a semi-autonomous bipedal vehicle based on passive dynamic walking (PDW) principles is proposed. PDW is known as a mechanical system, which is designed to walk down on a shallow slope without active control. To date, some bipedal walking robots have been developed to carry a person on uneven terrains. However, they don't utilize a PDW mechanism; nor they don't use the balancing ability of a human as like a bicycle or motorbike. This paper describes the basic structure of the PDW based human balancing bipedal vehicle, shows the simulation for confirming the feasibility, and reports the test ride of the prototype machine.

302 踵・足首・足趾を有する受動歩行ロボットによる歩行の実現(歩行ロボット,OS-17 ロボットのダイナミクスと制御,総合テーマ「伝統を,未来へ!」)

By recent researches, heel and toe of human is clarified important element in human walking. However, previous many researches of passive dynamic walking has omitted heel and toe from foot, and these researches has hardly been argued about the influence that heel and toe gives to passive dynamic walking. So, the purpose of this study is to clarify effect of heel and toe in passive dynamic walking. As a first step in this study, this paper clarify that passive dynamic walker with heel, ankle and toe enables stable walking. Experimental results showed that passive dynamic walker with heel and toes enable stable walking.

Generating Gaits for Biped Robots Using Multiple Dynamic Passivization of Joint Control

In the research field of bipedal locomotion, a central pattern generator (CPG) and passive dynamic walking (PDW) have attracted much attention. In this paper, we describe a motion control system for biped robots based on dynamic joint passivization. Our motion control system is based on a mixture of the CPG and PDW, that is, the multiple dynamic passivization of joint control (MDPJC). Our intention is to make the joint control of the swing leg temporarily passive in the swing leg phase. The important part is the passive phase time and the switch timings of the joint control. We optimize the switch timing parameters using simulated annealing with advanced adaptive neighborhood (SA/AAN). Experiments using the motion control system based on multiple dynamic passivization of joint control successfully generated energy efficient walking and enabled superior gaits.

2A2-E21 受動動的歩行における位相軌跡を用いた歩行制御手法

In recent years, research on biped walking robots has been focused on passive dynamic walking. The most important benefit of passive walking is low energy consumption; however, the walking itself is not robust and cannot be sustained without control. To minimize the energy that is used for control, we propose a simple switching control method based on phase trajectory. In this paper, we simulate a planar passive biped walker descending a moderate slope and apply the proposed walking control method. A significant improvement in sustainability of walking was achieved with minimal use of energy.