Non-single-cycle gait control method for biped robot walking

Abstract

The invention belongs to the robot walking control technology field, particularly relates to a biped robot walking non-single period gait control method and aims to switch non-single period gaits into single period gaits through parameter perturbation. The method comprises steps that, each step which is based on a hip series-connection elastic driver and is with upper body biped robot walking is sequentially divided into two driving stages and one free swinging stage, a fixed target point and a nominal parameter are determined, a first driving stage duration and a second driving stage duration of walking are set to be perturbation parameters, largest perturbation amount and smallest perturbation amount are determined, and a search grid is established; whether a possible smallest value of the first driving stage duration through perturbation is greater than or equal to prediction output of all nodes in a calculation grid is determined, and use time of optimum parameter perturbation is selected, if yes, control parameters are updated through establishing a Poincare mapping rapid estimation model; if not, the control parameters are updated through establishing a partial step rapid estimation model and the Poincare mapping rapid estimation model.

Description

technical field [0001] The invention belongs to the technical field of robot walking control, in particular to a non-single-cycle gait control method for a biped robot walking. Background technique [0002] Limit cycle walking is an important type of biped robot walking mode, which has advantages in energy efficiency and speed. The limit cycle walking gait presents periodic characteristics, and the gait sequence is orbitally stable, that is, a stable limit cycle can be formed in the phase space, but it does not have local stability at any instant in the gait cycle. Since this walking mode imposes fewer artificial constraints on the robot's motion and makes full use of the robot's own dynamic characteristics, many studies have shown that the limit cycle walking of biped robots will present rich non-single-cycle steps such as bifurcation and chaos. state. [0003] Using the hip series elastic driver to support the upper body and complete the energy supply through the energy ...

AI Technical Summary

Problems solved by technology

The traditional OGY method is simple in form, and can quickly control the non-single-cycle gait when the accurate target fixed point and the corresponding A, B matrix are known and the perturbation conditions are satisfied. However, when we implement the OGY method, we find that there are the following Problem: On the one hand, for a fixed point s far away from the target * state s, perturbation dp i =p i -p * =-K T (s-s * ) may be too large, resulting in abnormal parameter values, resulting in a huge change in the dynamics of the robot, and even causing the robot to fall in the experiment, which is poor in feasibility; on the other hand, if the perturbation size is limited, only reasonable If parameter perturbation is performed, in chaotic gaits with ergodic characteristics, the OGY method usually waits for a long time to run to the state that meets the conditions, while in bifurcated gaits without ergodic characteristics, if the perturbation Momentum always exceeds the limit, it will never be able to meet the implementation conditions of the OGY method, and the bifurcation gait cannot be stabilized

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