Compensation-based compliance control system and method for series elastic actuators

Abstract

The invention belongs to the field of compliance control over robots, and particularly discloses a compensation-based compliance control system and method for series elastic actuators. The method comprises the following steps of obtaining l<c><t> according to an impedance model P<k> and the preset target positions / angles l<d><t> of load ends of the series elastic actuators at the current moment; obtaining delta l<dob><t> according to inverse nominal models P<ln><-1> of load dynamic models of the series elastic actuators and the actual positions / angles l<t> of the load ends of the series elastic actuators at the current moment; obtaining delta l<f><t> according to l<c><t> and l<t>; and calculating to obtain l<t> according to l<c><t> and P<ln><-1>, calculating the actual target positions / angles l<r><t> of actuation units at the current moment t based on delta l<dob><t>, delta l<f><t> and l<t>, and finally controlling the actuation units of the series elastic actuators to track the actual target positions / angles l<r><t> in real time so as to realize real-time tracking of the target impedance by the series elastic actuators. The control system and method have the advantagesof being capable of realizing the compliance control over the series elastic actuators, high in control precision, good in effect and the like.

Description

technical field [0001] The invention belongs to the field of compliance control of robots, and more specifically relates to a compensation-based compliance control system and method for serial elastic drivers. Background technique [0002] Joint compliant actuators can enable robots to interact safely with humans or the environment. As a typical compliant actuator, Series Elastic Actuators (SEA) introduce elastic elements in the structure, which has safety, external impact absorption, energy storage, and cost reduction. and other advantages, such as figure 1 As shown, the series elastic actuator includes an actuator and a load, and the actuator and the load are connected through an elastic element; at the same time, in terms of control, the robustness of force output can be improved. Therefore, serial elastic actuators are widely used in robot joint drive control. [0003] In order to achieve compliance, the contact resistance is generally changed by adjusting the contact ...

AI Technical Summary

Problems solved by technology

In terms of control accuracy, the introduction of elastic elements makes the system more complex and makes the system more susceptible to disturbances, resulting in a decrease in control accuracy and robustness

The dynamic characteristics of the load (such as connecting elements, joints, etc.) will also greatly affect the control effect, and the traditional control method does not properly compensate the above factors

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