Day 13 – Jan 22nd, 2016

We finished assembling the drive train; we also finished a prototype linear punch that has two springs and an octagonal head. This linear punch will be attached on a retractable arm for the height limits and needs to also have an intake; a level of power is needed to propel a large boulder with just the impact of a linear punch also. The drive train is looking stable, now we need to focus on electrical boards.

Day 21-2
Working on the finished drive train

After many attempts, one of the lead programmers was finally able to re-image the RoboRio. A subgroup of programmers took over and started downloading software into the RoboRio. They also demonstrated their musical abilities while waiting for the downloads to finish. The router was installed in Sullee, our 2015 robot for testing with the new drive train code.

A subgroup of the mechanical team used continued development of the linear-punch shooter mechanism. An octagonal ball punching plate was manufactured out of plywood and installed on the end of the Rev Rail extrusion. Heavier springs were installed. A second subgroup reworked some of the AndyMark 8 inch pneumatic wheels that had been assembled the day before because it was found that #8 screws had been used in some locations where #10 screws were supposed to be used. A third subgroup assembled the bearings, axles, sprockets and chains into one the second frame tube. Four hubs were scrounged from around the lab so that four wheels could be installed onto this second frame tube assembly.

The electrical team started testing the handheld throttle made from an old battery drill. It worked well. The student noticed that the trigger assembly from the drill already had an integral reversing switch to the external reversing switch was removed. The wiring was a tight fit around the trigger assembly causing some of the wires to be pinched and be pressed against sharp edges of the trigger assembly. Some bits of the drill shell were cut away to make more room for the wiring. Once fully assembled, a final test caused the fuse to instantly vaporize as soon as the trigger was pressed. After much head scratching and troubleshooting, it was found that the trigger assembly itself was faulty. That was probably why the drill was scrapped in the first place.

 

A DVM was used to verify that when the body of the trigger mechanism was squeezed by hand, it would cause a short circuit. This did not occur with a trigger assembly removed from a second scrap drill so the second trigger assembly was installed in place of the original one. The handheld throttle was assembled one last time and was tested successfully.

The utility arm subgroup updated the calculation spreadsheet to make it more readable. It was also updated to add calculations to show the forces on the pivot if a pair of cables were to be used to hold the arm while scaling, the tension on those cables and the torque on the pivot of the arm due to estimated the weights of the collector mechanism and the linear punch mechanism.

Utility Arm Calculations

Here is a video of our programmers celebrating.