Force Torque Sensor (FT Sensor)

A force-torque sensor measures the six-axis wrench (three forces Fx, Fy, Fz and three torques Tx, Ty, Tz) applied at a robot's wrist or end-effector. FT sensors are essential for contact-rich and assembly tasks where pure position control would either miss contacts or apply excessive force. They enable impedance and admittance control loops, detect slip and collision, and provide rich sensory inputs for learned policies. High-precision FT sensors from ATI and Robotiq are standard in research labs; MEMS-based low-cost sensors are increasingly viable for production deployments.