US 11,866,256 B2
Climbing robot with compliant pinion drive
William J. Fosnight, Windham, NH (US); John G. Lert, Jr., Wakefield, MA (US); Michael Duquette, Candia, NH (US); Martin R. Elliott, Bedford, NH (US); Julian Warhurst, Portsmouth, RI (US); Charles W. Su, Stratham, NH (US); and Alan Grant, Nashua, NH (US)
Assigned to Walmart Apollo, LLC, Bentonville, AR (US)
Filed by Walmart Apollo, LLC, Bentonville, AR (US)
Filed on Sep. 11, 2019, as Appl. No. 16/567,881.
Claims priority of provisional application 62/731,300, filed on Sep. 14, 2018.
Prior Publication US 2020/0087067 A1, Mar. 19, 2020
Int. Cl. B65G 1/04 (2006.01); B25J 5/00 (2006.01); B25J 9/00 (2006.01); B65G 1/137 (2006.01)
CPC B65G 1/0492 (2013.01) [B25J 5/005 (2013.01); B25J 9/0009 (2013.01); B65G 1/1373 (2013.01)] 22 Claims
OG exemplary drawing
 
1. A mobile robot configured to travel in a vertical or inclined passage within an automated retrieval and storage system, the passage comprising a linear drive mount, the mobile robot comprising:
a compliant drive assembly for moving the mobile robot in the passage, the compliant drive assembly having:
a hub for supporting a wheel, the hub comprising a first spline;
a shaft having a second spline, the shaft configured to be rotated about an axis of rotation by a motor, the shaft further configured to be extended axially along the axis of rotation;
a drive gear mounted on an end of the shaft, the drive gear configured to move into engagement with the linear drive mount upon extension of the shaft;
wherein the first and second splines are configured to prevent jamming of the drive gear against the linear drive mount when the drive gear moves into engagement with the linear drive mount upon extension of the shaft, the first and second splines configured to prevent the jamming by providing rotational play between the first and second splines, the rotational play allowing a degree of free rotation of the drive gear relative to the linear drive mount.