Pick and Place Control of 3-DoF Robot Manipulator Using Linear Quadratic Integrator
Chika Alicia(a*), Adnan Rafi Al Tahtawi (a), Martin (a)

a) Politeknik Negeri Bandung, Department of Electrical Engineering, Bandung, 40012, Indonesia
* chika.alicia.toi20[at]Polban.ac.id

Abstract

This study proposes a pick and place control strategy for a 3-DoF robot manipulator based on linear quadratic integrator (LQI). The linear model of the 3-DoF robot manipulator is derived using an independent joint control approach, where the coupling factors between joins that cause nonlinearity are considered as disturbances. This model produces 6 state variables and 3 input signals. From the linear model obtained, an LQI controller was then designed so that the robot could carry out pick and place missions with good behavior. The controller is designed by setting a Q matrix where the angular state weight is set to be 100 times greater and the error state weight is set to be 1000 times greater than the control signal weight in the R matrix. This aims to produce a fast transient response to the angular and error states. The angle set-point of each joint is generated from inverse kinematics by inputting the pick and place target coordinates. Simulation results with the LQI controller show that each robot joint can reach the desired angle with a settling time of 6.4 s for joint 1, 8.1 s for joint 2, and 5.8 s for joint 3. The hardware test results also show that the robot^s behavior in pick and place missions using the LQI controller is better than without the controller.

Keywords: Arm robot- Linear Quadratic Integrator- State Space

Topic: Digital Industry 4.0