paper: Pivot - Crab-with-a-Twist

Thread created automatically to discuss a document in CD-Media.

Pivot - Crab-with-a-Twist
by: Clem1640

4-Wheel Independent Pivot Drive allows for dynamic and controlled reorientation (twisting) of the chassis in Crab drive mode. The mathematics behind two different Crab twist modes are exploreed.

Team 1640 (Sab-BOT-age, Downingtown PA) developed a 4-wheel independent Pivot Drive-Train. This Drive-Train was first utilized in the team’s 2010 FRC robot, DEWBOT VI. This drive-train utilizes independent drive and steering motors to each of the (4) wheels (so, 8 motors total for the drive-train). As compensation, the drive-train is very flexible and suited to a variety of control modes. Basically, it is a “fly-by-wire” drive-train. This paper explores the mathematics behind adding a dynamic chassis twist to crab-drive. Two different dynamic twist modes are described. Worksheets are included.

Pivot - Crab with a Twist.pdf (1.28 MB)
Pivot Twist 1.xls (45 KB)
Pivot Twist 2.xls (1.95 MB)