Older blog entries for Petar.Kormushev (starting at number 49)

Kinematic-free Position Control of a 2-DOF Planar Robot Arm

The video demonstrates a novel concept for kinematic-free control of a robot arm. It implements an encoderless robot controller that does not rely on any joint angle information or estimation and does not require any prior knowledge about the robot kinematics or dynamics.

The approach works by generating actuation primitives and perceiving their effect on the robot’s end-effector using an external camera, thereby building a local kinodynamic model of the robot.

The experiments with this proof-of-concept controller show that it can successfully control the position of the robot. More importantly, it can adapt even to drastic changes in the robot kinematics, such as 100% elongation of a link, 35-degree angular offset of a joint, and even a complete overhaul of the kinematics involving the addition of new joints and links.

The proposed control approach looks promising and has many potential applications not only for the control of existing robots, but also for new robot designs.