Bot having high speed stability

摘要

An autonomous transport vehicle for transporting items in a storage and retrieval system is provided. The autonomous transport vehicle includes at least two drive wheels and a controller, where each drive wheel is independently driven and a drive wheel encoder is disposed adjacent each drive wheel. The controller, in communication with the drive wheel encoders, is configured to determine a kinematic state of the autonomous transport vehicle within the storage and retrieval system based on incremental data from the drive wheel encoders only and independent of drive wheel slippage.

主权项

1. An autonomous transport vehicle for transporting items in a storage and retrieval system, the autonomous transport vehicle comprising:
a frame; a controller; at least two independently driven drive wheels mounted to the frame; and at least one caster wheel mounted to the frame and having a releasably lockable swivel lock configured to selectively lock and unlock swiveling of the at least one caster wheel so that when unlocked the releasably lockable swivel lock allows swiveling of the at least one caster wheel relative to the frame and when locked prevents swiveling of the caster wheel relative to the frame; wherein the controller is configured to effect locking and unlocking the releasably lockable swivel lock during a transport of items through the storage and retrieval system based on a predetermined kinematic state that correlates a speed of travel of the autonomous transport vehicle and a turn angle of the autonomous transport vehicle.