Table 3.

Example Metrics for Measuring Multi-Robot Assembly Performance

Metric	Category	Measurement Description	Units
Efficiency	Computational Complexity	Complexity of assembly strategy	O-notation
		Impact of using alternative assembly strategies	O-notation
		Single- versus multi-robot program complexity	O-notation
	Effort Efficiency	Programming time duration	Seconds
		Optimization/tuning duration	Seconds
		Commissioning versus use timing	Seconds
		Single- versus multi-robot program timing	Seconds
		Single- versus multi-robot cost	Monetary units
	Process Quality	Ratio of assembly successes to assembly failures	Seconds
		Mean time to failure	Time or cycles
Timing	Process Timing	Average time to complete a single assembly	Seconds
		Maximum time to complete a single assembly	Seconds
		Minimum time to complete a single assembly	Seconds
		Standard deviation of assembly times	Seconds
		Impact of using alternative assembly strategies	Seconds
		Sensitivity to parameter changes	Seconds
		Time Spent performing assembly versus other motions	Seconds
		Time required for single- versus multi-robot con- figurations to complete assemblies	Seconds
Motions	Displacement	Average positional error from the initial assembly search pose to the final assembly pose	Meters
	Motion Effort	Distance traveled during assembly process	Meters
		Joint displacement during assembly process	Radians/degrees
		Energy expended during assembly process	Watts
		Distance traveled performing assembly versus other robot motions	Meters
Forces	Force Transfer	Maximum incurred force measured by the robot on any given axis	Newtons/Newton-meters
		Average incurred force Measured by the robot on any given axis	Newtons/Newton-meters
		Maximum and average forces measured independently at the tool, assembly part, and fixture	Newtons/Newton-meters