Segway PT i2 Getting Started Manual page 57

If the Stick Shake Warning occurs while riding, slow down. If the Stick
Shake Warning persists, come to a stop and safely step off. Do not
attempt to ride again until the condition that caused the persistent
Stick Shake Warning has been identified and corrected.
If the Stick Shake Warning occurs while you are stopped or stuck,
step off immediately and do not attempt to ride again until:
You are clear of all obstacles and slopes.
You are certain that you did not experience a Safety Shutdown.
For additional information, see "Safety Shutdown"
on page 42.
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