Set the initial movement
Use the speed at the start of the stop and the mass moving in that direction.
HOISTING & TRAVEL / TOOL 20
Crane Stopping Distance Calculator
Compare how travel speed, control delay and net deceleration affect a simple crane stopping envelope.
Before you start: required inputs
- Record the speed immediately before stopping and the total translated mass.
- Obtain the response delay and net deceleration from measured motion data or the proposed control and brake model.
Calculation diagram
A PRACTICAL WALKTHROUGH
How to use this calculator
Describe delay and braking
Set the time before deceleration begins and the constant net deceleration after that delay.
Review the two distances
Add delay travel and deceleration travel. Use the graph to see the assumed speed history.
Stop from 30 m/min
THE INPUTS
30 m/min, 20,000 kg moving mass, 0.5 s delay and 0.25 m/s² net deceleration.
THE RESULT
Delay travel is 0.25 m and deceleration travel is 0.50 m: 0.75 m total over 2.5 s. Translational kinetic energy is 2.5 kJ.
What does the result mean?
01
Delay adds distance before the assumed deceleration even begins.
02
Deceleration distance varies with the square of initial speed when deceleration stays constant.
03
The kinetic-energy output excludes rotating inertia and is not a complete brake heat or torque selection.
Watch for this
Entering brake response time as deceleration time, which combines two physically different parts of the stop.
Formula & model conditions +
s_total = v t_delay + v² / (2a)
t_total = t_delay + v/a
E_translation = ½ m v²
- Speed stays constant during the delay, then decreases linearly to zero.
- Level travel and translational kinetic energy only. The entered net deceleration must already reflect driving and resisting forces.
- Rotating inertia, wind, downhill motion, load swing and brake torque selection are outside this model.
Common questions
Does this determine the position of an emergency limit switch?
It provides one motion estimate. Limit placement also depends on verified worst-case stopping behavior, buffers, clearances and the applicable requirements.
Does the load stop swinging when travel stops?
No. Suspended-load swing is outside this translation model.