Having mentored many build seasons (this will be my 10th), it's amazing the patterns that repeat. Pattern 1 is just how quickly build season flies by! Pattern 2 is just how many small details crop up at the last minute.
At the end of week 6, the robot looks 90% complete, we got our first "software bring-up", and ran all the motors for the first time. Great progress from the team, still with 2 weeks to go until competition.
Major systems came together - we had to disassemble a lot of the chassis to get the elevator mounted. Once the mounting was in place, we could start putting everything back together! While we manufactured the elevator tubes in house, most structures needed gussets to hold things together and transfer load - many thanks to friends who have CNC routers in their garage and helped make some parts for us!
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| Yes, those stickers say 'right front' and 'left front'. |
Very tall robot! With all the mechanical bits attached, we could manually verify the height and extension of the elevator. Looks great!
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| I think the battery is supposed to go inside the robot... |
Mechanically complete for the first time! (foreshadowing?) We got the intake mounted to the end of the elevator, and verified its position over the bumpers for ground pickup and at maximum height for scoring on the upper shelves and posts.
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| If we built this large wooden intake... |
Then we hit our next major hurdle. We use a system of belts and pulleys to spin the intake wheels and rollers, and for some reason our mechanical pieces didn't exactly match our CAD dimensions, so the belts didn't fit. With limited stock of belts, we had to improvise and create our own tensioning systems to try and get the rollers spinning correctly.
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| Figuring out tensioning as things didn't quite fit. |
"For some reason" was figured out later. Firstly, while the 1:1 drawings a match drilling works reasonably well, belt tension really wants high fidelity center to center distances. We made better use of the digital readout on our manual mill to improve that aspect on our V3 intake. Also present on this V2 intake were 3D printed pulleys. With the wrong pitch diameter. The belts we chose to use didn't fit as they were too tight, so all the hurdles here were due to dealing with oversized belts that we happened to have laying around. Again for V3, the pulley drawings were corrected and printed again.
Belt tensioning work complete, the intake got re-mounted onto the elevator. Just like in software, this intake was built to an interface - 4 bolts and 1 electrical connector is all that is needed to attach an intake. We are planning to test and iterate on the design (including the belts and pullets), and so long as we keep the 4 mounting holes in the same place, we can swap out a new intake with ease.
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| Intake attached for the... second time. |
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| We also started using the 'safety bar', which securely held the elevator so we could work on electrical or the intake. |
End of Saturday week 6, 2 weeks to go. We've tested that the drive motors works, and the elevator motors work. We re-attached the intake and went to test that motor. And ran into electrical and software configuration issues. Not the best way to end the week, but better to catch these issues now that on the competition field! We'll check back next week to see if we resolved the issue!
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