Force-Controlled Assembly: Four Implementations
Four common routes
| Route | Principle | Fits when |
|---|---|---|
| Current-loop estimation | Infer contact force from motor current | Insertion tasks with moderate tolerance |
| Joint torque sensing | Torque sensors in each joint | Compliant control is needed across the arm |
| Wrist force and torque sensing | Measure three forces and three moments at the wrist | Precision insertion, polishing and deburring |
| Passive compliance | Elastic structure absorbs misalignment | Large positional offsets in shaft and hole assembly |
Selection advice
- Decide first whether you need to control force magnitude, direction or moment.
- Check whether force and position control must switch quickly during the cycle.
- Include calibration and maintenance cost in the comparison.
Real performance depends on tooling, takt and calibration quality. Validate with a trial on the actual station.