Foot force and moment following control method of bipedal robot

Abstract

The invention discloses a foot force and moment following control method of a bipedal robot. According to the method, a double-spring damping model is designed, a force following controller is designed by using an LQR optimization method, and the following of the foot force and moment of the bipedal robot is realized; and the foot expected force and the foot expected moment are calculated by a planned ZMP (Zero Moment Point) distribution method, and finally, the ZMP following of the bipedal robot is better, and can adapt to a certain uneven ground. According to the foot force and moment following control method of the bipedal robot provided by the invention, the traditional ZMP following is abandoned, so that a control mode adaptive to the stable walking and the uneven ground of the bipedal robot can be realized, the foot expected force and the force moment that enable the robot to stably work are directly calculated, and the following of the foot force and the force moment is realized by directly controlling the foot expected force and the force moment, so that stable control is carried out in a more intrinsic and easier implementation manner, the control response is faster, the capability of adapting to the uneven ground is stronger, and the ZMP following effect is very ideal.

Description

technical field [0001] The invention belongs to the technical field of robots, and in particular relates to a foot force and moment following control method of a biped robot. Background technique [0002] Zero-moment point ZMP is a very important concept in the research of biped robots, and it plays a decisive role in the walking planning and stability of biped robots. An important means to evaluate whether the biped robot walks stably is whether the actual ZMP can follow the planned ZMP well. The force and moment received by the foot can reflect the ZMP of the robot. Generally, the actual ZMP of the robot when walking on flat ground is calculated through the force and moment received by the foot. Therefore, by controlling the actual foot force and moment of the robot, Make it able to follow the planned force and moment, so as to realize the follow of ZMP and make the robot walk more stable. [0003] From a physical point of view, this method can enable the foot to always ...

AI Technical Summary

Problems solved by technology

However, using ZMP to follow to achieve all this has two disadvantages. One is that calculating ZMP on uneven ground is theoretically inconvenient and inaccurate, so it cannot reflect the walking state of the robot well. The effect of using the ZMP following control method alone on the flat ground will not be very good, and we cannot blindly pursue the calculated ZMP of the robot to follow the planning value.

On the other hand, due to the impact and error of the force sensor, the ZMP calculated from the force and moment of the foot is also very inaccurate. In addition to the theoretical error, the real ZMP of the robot calculated in this way is not true at all. It will inevitably affect the control effect

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