DEWBOT XVI Climber
- Needs to be easy for drive team
- Must be capable of hanging in switch center
- Must be capable of hanging on raised area of switch
- Robot must remain up when disabled
- Robot needs to be easily removed from switch after match by two students
- Robot must be removed from field and returned to pit without needing power
- One motor may be used
- Climber must remain entirely below 28" height prior to deployment
When the Shooter Arm was under consideration, it was intended that the Climber would be incorporated into this system. With the Arm abandoned, the Climber became a stand-alone mechanism.
Extensions are composed of 1" OD x 0.028" wall 4130 steel tubes with printed square linear bearings outside and bronze leadscrew nuts inside at the rear and ¼" 6061 Al hooks at the front.
Leadscrews are driven by a single NEO motor mounted on a custom shifting gearbox. Gear reduction ratios are 1:1 (for rapid extension under low load) and 4:1 (for lifting the robot). Gear shifting is pneumatically actuated (¾" x ½" stroke) utilizing a 4-tooth Andymark dog. The gearbox has an encoder mounted on the output shaft.
The gearbox has two output shafts each with a 28t HTD5 pulley; one for the right side extension and the other for the left side. The two output shafts rotate in the same direction, allowing normal right-hand leadscrews to be used for both extensions. Power is transmitted from these to 28t HTD5 pulleys on each of the leadscrews using 9mm wide belts: 205t on the left; 52t on the right. The leadscrews can be driven by hand using the 205t belt.
A 3/8" shaft extends from the gearbox between the two output shafts, rotating in the opposite direction. This shaft allows a hand drill to be used to drive the leadscrews without robot power.
Leadscrews are 3/8"-10 2-start 4140 steel leadscrews with right-hand thread (McMaster-Carr 98940A012). Leadscrew Nuts are
DEWBOT's climber deploys pneumatically and extends a pair of hooks via leadscrews. A shifting gearbox allows fast extension together with the power needed to lift the robot off the playing field. By using leadscrews, backdriving after game's end is avoided.