INTRODUCTION TO

ROBOT FORCE CONTROL

Updated 2014-09-03

What is robotic force control?

In which applications is it useful?

IN THIS LESSON

Today's industrial robots are in most cases programmed using a position control scheme: • The robot tool follows a prescribed trajectory in space

which has been pre-programmed. • Any deviation in the prescribed trajectory of the encoders

is compensated for by the control loop of the robot.

Robot Position Control

Position control works well for applications in which the robot tool has to go to a prescribed position and does not interact with a rigid environment or workpiece. For example:

Robot Position Control

Welding Painting Pick and place

Other applications require controlling not only the position, but also the applied force. For example, when you erase a blackboard, you need to: • move the eraser along the

plane of the board (position control),

• and exert a certain amount of force perpendicular to the board (force control).

Force Control

Examples of other applications in which the robot needs to control both the position and the force :

Robot Force Control

Polishing Part insertion Hand guiding

To use force control, the robot needs to process information about the force coming from a sensor, typically a 6-axis force torque sensor. Any deviation from the prescribed force measured by the sensor will be compensated for in the control loop and the robot joints will be actuated accordingly.

Robot Force Control

Learn More on the Robotiq FT 150 Force Torque Sensor

robotiq.com

TOOLS FOR

AGILE AUTOMATION