Monday, June 11, 2012

Week 10

This week, we completed building our Sea Perch and even had some time to test. We had some issues with wiring the control box, but after some troubleshooting, we found that our fuse on the circuit board blew and the ethernet cable plug had some issues. Since we did not have an extra fuse and would have to make a run to Radio Shack for a new fuse anyway, we just bridged the connection on the control box and added a 10 amp inline fuse near the battery, as the instructions on some other Sea Perch kits describes. The the 10 amp fuse will also be less likely to burn out, because our last fuse was 6.3 amp. And if this 10 amp fuse burns out, then we have 3 extra fuses which will be easier to replace than the 6.3 amp fuse because this inline fuse does not require us to take the control box apart and re-solder the board to replace the fuse. For our ethernet cable plug issues, we ended up cutting the broken ethernet cable plug and crimping a new one on, which solved our problem. After we fixed all of our control box issues, we proceeded with final assembly.

First we glued our low speed motor to the bar directly beneath the rotating bar, and glued the small 8 tooth gears to the same motor. We then slipped the large 40 tooth gears and the gear holders to the rotating bar and aligned the gears in plane with each other using the lego chain. Once we had the gears aligned, we drilled the holes for the gear holders into the rotating bar and drilled the holes which would connect the 40 tooth gears to the gear holders. After we dirlled all of our holes, then we bolted everything together, added the chain, and tested the design. all seemed to go well at first, but we found that the plastic lego chain kept on breaking because the chain was either too tight or too lose. Since adding or taking away one link from each chain would result in the chain breaking, we created a chain tensioner using safety wire.

Chain Tensioner:




After we adjusted our chain tensioner, we found that the lego chain was working as planned, so the next day we took the Sea Perch to the pool to test it.

Sea Perch after final assembly:




The tests went very well. The Sea Perch did not break in any way, and the water proof motors worked flawlessly.


Speed Test: 



Maneuverability Test:



From all of our tests, the only issues we had was that our Sea Perch pulled to one side, which we predicted would happen after observing how one propeller wobbled when spun and the other propeller worked great.

We also finished our final report and final presentation and in the process of practicing our presentation.

Friday, June 1, 2012

Week 9

Accomplishments for this week:

-Completed waterproofing box for motor, installed motor.
Meet the new box. (Same as the old box.)


-Installed rotating pipe and attached motors.
Assembly nearing completion.

-Largely completed wiring.
-Assembled most of the ROV
Motors have since been attached.

-Completed designs for sprockets for the chain.
8-tooth gear for drive beam.

40-tooth gear for motor beam.


-Began to put together final presentation.

Goals for next week:
-Finish control box.
-Finish assembling and test the ROV.