Iterave design, 2011

[Hawiian Cadder]

it seems like every year i learn a lot by watching competitions and seeing what design methodologies and techniques work, and how they manage to build robust, light, effective robots. however i always forget what i learn by the next season. so this year i decided to completely re-design our robot every two weeks, after watching what other teams do well. the basic design remained similar through every iteration. the strategy my team decided on in the beginning, was a robot with a rolling gripper, with a elevator that could score on all 3 rungs. my main goal through the iteration was to do the same thing better with less weight. we are always overweight. below are some renders of the different versions.




this is the original CAD of the robot, specs:
4 cim drive, 14 feet per second. 6 wheel tank drive. the wheels on the ends are omni wheels.

lift powered by the fisher price in a dewalt gearbox with anti back-drive pins intact.

the wrist is a rs550 in a 81-1 gearbox with another 6-1 in sprocket reduction.

the roller is powered by another rs550 in an 81-1 gearbox

weight, 119.9, according to the CAD, it was 112



the second version was put together largely the same way.

the drive speed remained the same. the only difference is the conversion to 8 wheels instead of 6.

the frame was changed to 4*2 tubing, and the drive is now cantilevered.

the lift was changed from a rolling design to a telescoping channel lift with nylon sliders. the method to power it remained the same, the FP in a dewalt transmission.

the manipulator remained largely the same, the motor powering the roller and the motor powering the wrist were both moved, they are on the manipulator near the wrist axle, this makes it lighter and more compact. the torque on the wrist is much less. another change is the electronics box, it was changed to be tall and have a smaller footprint. this allows the minibot deployment to move from the top of the box to the side.

weight according to cad, 92 lbs, not including wire or chain.



the tough-boxes have been changed to modified AM shifters. the high ratio is 16 feet per second, and the lower one is around 6.5.

all the axles have been changed to hollow shafts, and the tubes in the frame have been changed from 2*4*.125 to 1.75*3*.125. this reduces weight, and removes the need to pocket the frame. the lift has been changed from pocketed .25 thick channel, to un-pocketed .125 thick channel. the manipulator has a less CNC dependent design, which uses bolts instead of rivets to hold together. the gearboxes on the wrist and roller have been changed to rs550's in am planetary, and gems.


weight. 83 lbs. not including wire, includes chain this time.

sorry about the color of the cims being wrong on the last render, my team likes to prank me by changing the appearance of things in the CAD.