AiVibePower and Force Limiting (PFL)
Power and force limiting is a collaborative operation method in which contact between a robot and a person may occur, but the robot's design and safety functions keep forces and pressures below biomechanical limits for the body regions at risk.
PFL robots detect and limit contact through joint torque sensors, motor current monitoring or sensitive skins, combined with lightweight, rounded designs and limits on speed, force, power and momentum. Safety-rated functions stop or reverse the robot when a collision is detected. ISO/TS 15066 provides permissible force and pressure values for body regions and distinguishes quasi-static contact, where a body part is clamped, from transient contact, where it can move away.
PFL is the method most associated with cobots, allowing operators to work alongside robots without fixed guarding for tasks such as screwdriving, small-part assembly, packaging and machine tending. It suits applications where contact is possible but the payload, speed and tool are benign.
Contact limits depend on the whole application: a sharp tool, a heavy part or a clamping point can make an otherwise compliant robot hazardous. Limits are verified with force and pressure measurement devices at the identified contact points. Speeds are typically lower than in fenced cells, which affects cycle time.
Key points
- Contact is permitted but kept below biomechanical force and pressure limits
- Relies on safety-rated force, torque, speed and power monitoring
- ISO/TS 15066 gives limits by body region and contact type
- Tools, workpieces and clamping points must be assessed
Where AiVibe comes in
AiVibe designs and manufactures the AiAmbA AI Factory, whose edge devices and AI agents let people talk to robot controllers in plain language. Robotics perception is an AiAmbA use case, and robot safety functions follow ISO 10218 and never depend on the AI layer.