Two-channel Bilateral Control of Delta Robots with Gravity Compensation

This paper presents three-dimensional bilateral delta robots based on a novel transfer-function-based two-channel bilateral control system. This configuration has proven to provide better control perfomance while only requiring two channels of communication, for position information exchange, as opposed to the traditional four-channel bilateral control method. The proposed three-dimensional bilateral Delta robot architecture proves to have good performance, however it is affected by gravity, and therefore, in order to ensure smooth operation of the delta robots we introduce a compensation for gravity on the bilateral control system, based on the analysis of the kinematics of the delta configuration. In this paper, we discuss the application of transfer-function-based two-channel bilateral control to three-dimensional delta robots, and the accuracy improvement obtained by the application of gravity compensation to the two-channel bilateral control.