Can you detect if two parts overlap during a motion study in SolidWorks?

Short Answer

Yes — in SolidWorks, you can detect whether two parts overlap during a motion study by using collision detection while dragging or animating components in an assembly. This is the most common professional method for checking interference during movement. It works best in assembly motion workflows, but it may miss issues if collision checking is not enabled at the right stage.

What You Need to Know Before

Warning: Collision results in SolidWorks depend heavily on mate behavior, component position updates, and the motion study type you use. A common failure is assuming a Basic Motion or Animation result automatically confirms clearances when collision detection was never turned on during the actual movement test.

How to Detect Overlap During a Motion Study in SolidWorks

• Command: Collision Detection

• Shortcut: No default keyboard shortcut

• Quick Steps:

  1. Open the assembly, then go to the Move Component tool from the Assembly toolbar or Tools > Component > Move.
  2. In the Move Component PropertyManager, enable Collision Detection and choose Stop at collision or Physical Dynamics.
  3. Drag one part through its motion path, or run the assembly movement relevant to your study, and watch for contact stopping points or overlap behavior.

Variables & Settings

• Key Setting: Stop at collision

• Expert Setting: This option stops the moving component the moment SolidWorks detects contact with another part, which is the fastest way to confirm overlap risk during motion. If you use Physical Dynamics, SolidWorks simulates more realistic contact response, but it is slower and may behave differently depending on mates and contact conditions.

Why it Fails

• Cause 1 (Geometry): Lightweight, simplified, or imprecise geometry can prevent accurate contact detection, especially with small faces, imported bodies, or narrow clearances.

• Cause 2 (layers/Locks): Fixed components, suppressed mates, or locked motion from assembly constraints can prevent parts from reaching the overlap condition you are trying to test.

• Cause 3 (Command/Logic): A Motion Study animation can visually show parts passing through each other if collision detection or physical contact was not explicitly enabled during the movement method being used.

Quick Fix & Best Practice

• Quick Fix: Use Move Component > Collision Detection > Stop at collision, then test the moving part manually before trusting the motion study result.

• Manager’s Verdict: For most production assemblies, use collision detection first for quick validation, then use Interference Detection as a second check on suspect positions. Do not rely on visual animation alone for clash approval.

FAQ

Can SolidWorks stop parts when they touch in an assembly?

Yes, Stop at collision can stop the part as soon as contact is detected.

Is Interference Detection the same as collision detection in SolidWorks?

No, Interference Detection checks overlapping geometry at a position, while collision detection checks contact during movement.

Can Motion Study show overlap without warning?

Yes, if collision or contact settings were not enabled, components can appear to pass through each other.

.