Off-season builds are always good; we're converting last year's practice chassis into a pneumatically-actuated slide drive that picks up 8" inflatable orange rubber balls (a local grocery had them on sale for $1). It also has to have 2014-legal bumpers - only five of our student members were on the team last time we made bumpers.
You can't have a robot or portions pre-built, if the fabrication rules are similar to other years. Having a pre-built chassis may be helpful for prototyping, however.
You need to teach team members how to use your tools now, rather than trying to pack the learning curve into build season. That includes machine and hand tools, programming tools, CAD, communications/organization tools (e.g. your Google Docs or whatever you use), leadership tools, and so forth. Teach good habits now, because it's way too easy to pick up bad habits during build season. (E.g. use the drill press, not a hand drill, sweep up regularly, and where to put things away.) We're also going to do at least one exercise that will simulate an accelerated "first few days" of build season using an old FRC game, with the end goal being a robot design with specific large-scale dimensions but little detail on the fine stuff.
Along the lines of classes, we're taking one session per week and having the students go through four mini-classes (25 minutes with 5 minute breaks between) in four completely different things each session. Our first two sessions I did "Engineering Process" and "Drivetrain 1: acceleration". Others did "the 2015 control system," "game strategy and robot concept," "soliciting corporate sponsorships," "leadership," "chairman's award," and one more I can't think of. Monday, I'm doing "Drive Train 2: speed and steering".
If your budget allows, stock up on all the stuff you're likely to need. It's great if you can start fabrication as soon as you have a design. You know you'll need motor controllers, motors, metal stock, fasteners, wire, connectors, tie wraps, something to attach the control items to, and so forth. We also keep a variety of inexpensive sensors on hand so we can experiment to see what works. Also check your tools - and try to have everything you'll need, and multiple of the tools you use a lot (like 5/32 allen wrenches).
Now would be an excellent time to standardize on a few specific fastener threads. Based on our large use of AndyMark wheels and gearboxes, but wanting to be able to buy inexpensive fasteners locally, in 2014 we decided that we would use 10-32 for all of our #10 applications, and coarse threads for all of our smaller (8-32, 6-32, 4-40) and larger (1/4"+) sizes. We separated all of the metric threads, 10-24s, and non-10-32 fine thread fasteners to a separate set of boxes that are
only used when we are trying to mate to a specific COTS part. We use allen cap screws preferentially when space allows, but do not hesitate to switch to flat-head or round-head Phillips or other bit when appropriate. We try to skip cheese-head; it requires a chamfered hole but sticks up above the stock; that's the worst of both. Oh, yes - if you use a lot of flat-head or cheese head screws, by all means invest a few dollars in the bits which drill the through hole and cut the chamfer in one step!
I'm going on about threaded fasteners, but we're planning to switch this year to a much larger percentage of aluminum rivets. In addition to the rivets, we're going to stockpile drill bits, both to make rivet holes in the first place and to drill out when we need to do removals.
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Originally Posted by alecmuller
Also, depending on how literal you were by "basic frame", I highly recommend AndyMark's 2015 Kit-of-Parts (KoP) Drive Chassis as a starting place.
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Yes. For 2016, we opted out of the KoP, but we plan to purchase two AM-14U2's (2015 KoP chassis) before build season; starting last year, we build a "practice robot" which is essentially the same as our competition robot, so we can continue to improve after stop build day. Unless you're planning swerve or other "steered wheel" drive, you can do anything with this as a base kit. I've even roughed out how to make
two kiwi drive bases using
three AM-14U2s and six omni wheels.