DEWBOT III

From DEW Robotics
Revision as of 02:35, 13 August 2009 by MaiKangWei (talk | contribs) (Design Details)

Jump to: navigation, search
Dewbot III hangs a Ringer at Drexel

In 2007 we built DEWBOT III to play Rack 'n Roll.

Dewbot III turned out to be a good performer and scorer once we upgraded the gripper for the Philadelphia Regional. Key attributes of Dewbot III include:

  1. A drive-train and chassis with solid performance and reliability
  2. An reliable, easy-to-use Arm and Gripper capable of scoring quickly on the bottom two Rack courses
  3. Ability to climb ramps (for bonus score)
  4. Robot was logically laid-out and posed no significant maintenance problems

The team suffered from some process problems during build season. Dual Arm designs were pursued to the build season's end. We've learned from this and have subsequently improved our decision-making and Project Management skills and discipline.

What Dewbot III did not have were:

  1. Ramps or lifts for bonus scoring
  2. An ability to score (reliably) on the top Rack course
  3. An autonomous mode

No part of Dewbot III was designed using CAD.


DEWBOT III Build Season


Design Details

Drive Train
Dewbot III chassis and drive-train with mentor Ed Faller and student Cassie
Dewbot III possesses a drive-train and chassis having good performance and reliability. Drive-train is four-wheel-drive (4wd) Tank with Traction Wheels forward and Omni Wheels aft.
Arm
Following some teething problems (which were both technical and process-related in nature), DEWBOT III ended up with a very effective Arm for scoring on the lower and middle levels of the Rack. By gripping the Ringers from the OD, it was easy to pick up Ringers and they were generelly well oriented for scoring. Best of all, the Arm and Gripper did not interfere with the Rack when letting go of the Ringer and disengaging from the Rack.
An independent regulator let us set the pressure and therefore the closing force of the Gripper. In this way, we gripped Ringers securely, while avoiding collapsing them.
Bonus Scoring
DEWBOT III lacked any provisions to lift an alliance robot, but was designed to readily climb any ramp up to 30°.
Interference between bumpers and ramps lead us to quickly discard DEWBOT III's very nicely designed bumpers.
Programming
Electrical
Pneumatics
Full Onboard pneumatics system including Compressor and (4) Clippard storage cylinders. (2) regulators used, allowing for lower pressure and therefore lower force on the Gripper. (2) Users - the Arm Shoulder and the Gripper. In retrospect, the Shiftbox actuators should have been pneumatic as well in lieu of servos.
Since DEWBOT III started each match with the Shoulder in a neutral position, DEWBOT III was obliged to begin each match with the pneumatic system depressurized.
Autonomous Mode
Turned on Compressor. Got the Arm ready to work.
Weight
Team 1840's historical lightweight. Under 90 lb. Center of mass low and centered.
Bumpers
oo

People

DEWBOT III Students
DEWBOT III Mentors
Sponsors 2007

See our other robots at FRC Team 1640