Robotics & Automation worked example

Collaborative Robot Speed Limit with allowable transient transfer energy of 250 mJ: a worked example

Here is what the math looks like when conditions slip. We hold every other input steady and drop allowable transient transfer energy to 250 mJ, then walk the calculation through step by step. Estimate a power-and-force limited cobot TCP speed by relating allowable transient transfer energy to effective TCP mass, with a safety margin per ISO/TS 15066.

The inputs for this scenario

  • Allowable transient transfer energy: 250 mJ (the input this scenario stresses; the baseline uses 490)
  • Effective mass at the TCP: 4 kg (held at the documented default)
  • Safety margin multiplier: 0.8 x (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Indicative TCP speed ratio = allowable transient transfer energy / effective mass at the TCP (then take a square root and convert to mm/sec when reading the result).
  • Indicative TCP speed ratio (energy/mass) works out to 50 mm / sec at these inputs, and this is the headline figure for the scenario.
  • Raw ratio works out to 62.5 value at these inputs.
  • Conversion factor works out to 0.8 x at these inputs.
  • Effective mass at the TCP works out to 4 value at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where allowable transient transfer energy sits at 490 mJ and the headline result is 98 mm / sec, this scenario comes in 48.98% below the baseline at 50 mm / sec.
  • The practical read: the gap between this scenario and the baseline is entirely attributable to allowable transient transfer energy, so recovering it is worth quantifying in dollars before considering equipment or staffing changes. It is indicative only. Real safety acceptance requires measured transient and quasi-static force and pressure against the applicable body-region limits; geometry, sharp edges, and clamping (quasi-static) contact can require far lower speeds than this energy estimate suggests.

Results at a glance

  • Indicative TCP speed ratio (energy/mass): 50 mm / sec (headline result)
  • Raw ratio: 62.5 value
  • Conversion factor: 0.8 x
  • Effective mass at the TCP: 4 value

Run it with your numbers

  • To rerun this with your own numbers, open the live Collaborative Robot Speed Limit calculator, set allowable transient transfer energy to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.