A short move may finish before reaching its requested maximum speed. That can be normal behavior for an acceleration-limited motion profile.

Ideal constant-acceleration calculation; actual planners may use jerk-limited profiles.

What is happening?

Acceleration and deceleration need distance. When their required distances consume the move, the profile has no constant-speed segment. Jerk limits can further change the shape and achievable peak speed.

Check these five things

1. Record move distance and requested maximum speed.

2. Check acceleration and deceleration limits.

3. Identify whether the planner applies jerk limiting.

4. Compare planned velocity with actual velocity.

5. Evaluate cycle time using the complete profile.

Worked example

For an ideal symmetric profile with acceleration of 2 m/s² and requested speed of 1 m/s, acceleration and deceleration together require 0.5 m. A 0.2 m move cannot reach 1 m/s; its ideal triangular peak is about 0.632 m/s.

Quick diagnostic reference

The mistake to avoid

Increasing maximum speed may do nothing for a distance-limited move. Do not raise acceleration without reviewing load, mechanics, and drive capability.

How to verify the fix

Compare planner traces and cycle time at the approved settings. Confirm position accuracy and mechanical behavior remain acceptable.

Field-work boundary: These are educational diagnostic guides. Use the exact equipment manuals and approved site procedures. Electrical testing and machinery changes belong to qualified, authorized personnel; control hazardous energy and validate affected functions before release.

Technical reference

Oriental Motor: Technical reference and motion sizing. The examples and diagnostic tables above are original teaching material; they do not replace the product manual.

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