Design and implementation of improved sliding mode controller on 6R manipulator

In this work, we present an improved sliding mode control (ISMC) technique designed and implemented for control of 6R manipulator. Sliding mode control (SMC) is a well-known nonlinear robust method for controlling systems in the presence of uncertainties and disturbances and systems with complex dynamics as in manipulators. Despite this good property, it is difficult to implement this method for the manipulator with a complex structure and more than three degree-of-freedom because of the complicated and massive equation and chattering phenomenon as a property of SMC in control inputs. Here, the chattering phenomenon is eliminated by using an effective algorithm called ISMC and implemented to 6R manipulator by using a low-cost control board based on an ARM microcontroller with high accuracy and memory. The carrying load is considered as the uncertainty for the manipulator, while the dynamic load carrying capacity (DLCC) is considered as a robot performance criterion showing robustness of the controller. The results of simulations and experiments show that the proposed approach has a good performance and is suitable and practical to be applied for manipulators.