Time-optimal trajectory planning method for six-legged robots under actuator constraints

Abstract

Current studies on time-optimal trajectory planning centers on cases with fixed base and only one end-effector. However, the free-floating body and the multiple legs of the legged robot make the current methods inapplicable. This paper proposes a time-optimal trajectory planning method for six-legged robots. The model of the optimization problem for six-legged robots is built by considering the base and the end-effectors separately. Both the actuator constraints and the gait cycle constraints are taken into account. A novel two-step optimization method is proposed to solve the optimization problem. The first step solves the time-optimal trajectory of the body and the second step solves the time-optimal trajectory of the swinging legs. Finally, the method is applied to a six-parallel-legged robot and validated by experiments on the prototype. The results show that the velocity of the optimized gait is improved by 17.8% in contrast to the non-optimized one.

Design of Simulink-based 3D Hexapod Robot Model and Implementation of Hexapod Robot Foothold Planning

“…The Degree of Freedom (DoF) of most hexapod robots for one leg is 6. However, some hexapod robots do not have such a leg structure and do not have 6 DoF, such as the RHex robot [39] and six-parallel-legged robot [40] . The movement of the hexapod robot is controlled by robot gait.…”

A Fuzzy Logic Reinforcement Learning Control with Spring-Damper Device for Space Robot Capturing Satellite

“…In recent years, intelligent algorithms have been more and more applied to the control of robot systems [27][28][29]. Since the target satellite has a large initial velocity, the hybrid system after capture will be in a serious unstable state (e.g., involving overturning and rotation) and the traditional control method will make it difficult to complete its calm control.…”

Novel Reconfigurable Walking Machine Tool Enables Symmetric and Nonsymmetric Walking Configurations

“…aerospace [6], energy [7], precision machining [8]- [11], grasping [12]). The higher performance also benefits locomotion, as shown by multiple examples of robotic legs with parallel architectures [13]- [18]. However, their inherent disadvantages, such as complex kinematics and a reduced workspace when compared to the PKM's size still limit their applications.…”