Week 3: All Eyes on Us

Week 3

On top of CAD, our week 3 goals included getting our electrical components placed and starting to mount them into position, and build the mandatory bumpers. Robots flying across the field need something to absorb the inevitable hits!

The engineering teacher at the school has also been working constantly to get our CNC router and waterjet machines operating and controllable. This week the CNC was able to start running through some test parts, in preparation for the flurry of "final" parts that we'll need to start machining very soon!

CAD did come together and is over 95% complete as of Saturday evening. We did our first review, finding mostly finer details issues than large conceptual items to resolve. The students are really learning that the last 10% takes 90% of the time!

CNC enclosure

In house CNC machine, getting ready to cut some of our polycarbonate and aluminum sheet pieces. (spoiler - we cut some test items, but never actually got this together enough to cut robot parts... More on that later!)

Bearing holes need special attention.

All machines operate slightly differently, this test piece cut four ever-so-slightly different holes to verify how to define our future bearing holes.

Bumpers getting formed!

Bumpers are made from 3/4" plywood attached to 2.5" foam noodles, finally wrapped in red and blue canvas. The colors help designate the alliance colors at competition, and the foam absorbs shocks when 2 of these ~130p -pound machines make contact with one another.

Most placement was made by measuring the actual belly pan, as our design team was working on the robot mechanisms.

Our electrical folks marked out positions where components will lay, safely tucked in the belly of the robot! This year we will be using 7 brushless DC motors with built-in encoders to help software determine rotational speed and/or position!

Looks like a robot!

98% CAD complete robot! All systems exist and are mounted. Final touches are adding bolts into every capture to check for clearance and get a final weight estimate.

With the robot looking as good as it does, we wanted to share our creation. The students and mentors are good, but there's a limited number of us. We most definitely did not think about some things that would be present on other folks minds. We reached out to a few friends on some local teams (some of whom build very competitive robots!) and asked if they wouldn't mind poking holes in our design. Of course they would help us!

The first feedback we got was that this robot was way too simple. If we wanted to be successful we would need to severely increase the complexity of the design and software controls. Just kidding. A few items came up with force reconciliation in our main structure, some help with capturing bearings, and a recommendation on supporting our intake in the stowed position. Beyond that, our friends said this robot looked great, we should be able to have a lot of fun this season!

We should be able to score in all positions.

Once weights and materials are assigned to all components, OnShape - our CAD program - can compute things like center of gravity in our different robot positions. This will help make sure we don't fall over while trying to score points!

Next week is all about cutting metal (and plastic)! This robot will start to take shape very quickly!