What is the primary purpose of a force/torque sensor in assembly tasks?

• A. To measure only torque for tuning motor drivers.
• B. To provide visual feedback for alignment.
• C. To log temperature of joints.
• D. To measure contact forces and torques and enable compliant or spring-like behavior, or detect misalignment.

Answer: (D)

Force/torque sensors provide real-time measurements of the contact forces and torques at the robot’s end-effector. In assembly tasks, this lets the controller respond to how parts behave when they touch, guiding the motion with a compliant, spring-like behavior rather than rigid, hard contact. With this data, the robot can insert, clamp, or mate parts more safely and reliably by adjusting grip force, insertion force, and path in response to sensed interaction, and it can detect misalignment or unexpected resistance early to stop or correct the motion.

This capability specifically addresses interaction with the environment, which is why it’s the best choice. In contrast, measuring only torque for tuning motor drivers ignores the broader interaction context; relying on visual feedback comes from cameras or vision systems, not force/torque sensing; logging temperature of joints is handled by thermal sensors, not force/torque sensors.