We are considering opting out of the KOP chassis and building our own WCD. We are aware of the potential advantages of both but are wanting advice on the financial disadvantages. Specifically, will we be able to get our money’s worth with the voucher? If we are buying stuff from WCP and VEX for the chassis, will we be essentially forfeiting the voucher? What do other low resource teams buy with the voucher when they opt out?
For reference, we spend less than $500 (often way less) to build the robot typically.
Thanks
Keep the KOP chassis.
You could easily put the voucher to good use by getting plenty of compliant wheels, bearings, chain, pneumatics, electrical components, motors, etc. When I was with the team, we weren’t low resource but used the voucher for those items since we built a WCD frame.
If you haven’t already considered it, the kit frame can be useful as a test bed. Quickly get it running and use for prototyping. Also, having the same frame year-to-year can make things like building a practice bot more feasible.
If you’re going to opt out, I suggest having a good idea of what you want to replace it with. If you’re going with Vex/WCP, go to the Vex website and put together an order with everything you need. Motors, gear boxes, tubing, bearings, shafts, wheels, chain, sprocket, etc. That’ll give you an idea of how much you’ll be spending. Obviously, things can change (gear ratios, wheel size, etc), but that’ll be a relatively small incremental difference.
If you aren’t getting the drive train from AndyMark, there’s still other things you can get there. Gearboxes, Redline motors, motor controllers, a spare Roborio… there’s a lot of value there that you can use to start growing your team’s abilities if you have that “free” money.
Personally, I would not opt out of the KoP chassis if I was a team that spent under $500 per season.
Αsk yourself why you want a West coast drive over the kop chassis? With your budget I really recommend keeping the kit chassis. Even with the voucher you will end up spending more and you already don’t have much to work with.
One thing you might want to consider is re-using some of the gearboxes from past years, which is legal so long as you disassemble them first. That way, you can buy a KOP frame from Andymark for ~$200, and still have $250 to boot.
Seconded. The kit of parts drive train is really a good value. With your budget I would absolutely keep using it and focus on what goes on top of it.
Thirded. The KOP drive train is good enough for most applications, and the difference between mediocre and exceptional teams is almost always scoring mechanisms and manipulators.
We spend our AndyMark opt-out voucher on the same thing every year:
It’s definitely worth it for us, and the value of having additional roboRios and electronics around is incredible. Having robots to use as development beds for your controls group and programmers is massive.
That being said, it costs more than $500 to build a West Coast Drive, so I would not suggest blowing your entire budget on a drivetrain when the KoP drive is perfectly adequate.
We usually build a custom chassis every year and still take a KoP chassis. This year, last year’s KoP chassis was graciously donated to team that opted out and struggled with their custom design. As stated previously they are a solid investment.
A $500 robot budget is minimal and would require a multi-year investment for a WCD.
Our two speed WCD chassis cost $1,205 this year. This doesn’t include tax or shipping. We did reuse gearboxes from 2017 which are included in this price.
As a fellow low resource team - no.
Keep your KOP chassis if possible. If you opt out of the KOP and get the voucher, see if you can make a quick frame in the fall out of regular 2x1 instead. It doesn’t need to be a WCD.
You cannot build an equivalent chassis for $450 unless you already have a good bit of it from previous years. So unless you are changing wheels, gear ratios (IE not the gearbox that comes with the KOP) then you are really better off with the KOP chassis. It also sets a good bit of the design so you can concentrate limit resources on other issues.
As others have said, it’s probably a good idea to stick with the KoP.
If you state why you might be interesting in a WCD instead, perhaps some people on CD could give suggestions on how to achieve those goals with the KoPs drive base.
Andymark already provides a plethora of upgrade options, among them:
- Various wheel types – Mecanum, Omni, pneumatic, etc.
- Various mounts and brackets
- A pre-made superstructure
- Belt-to-chain conversion kits
- 3-cim gearbox
There are some other improvements that are a bit harder to find on the AM website but are easy to implement, such as adding encoders to the drive base, changing the gear ratios in the drive gearbox, modifying the dimensions other than the three “default” ratios, etc. etc.
I think it’s cheaper, faster, and more reliable to adapt the KoP drivebase to achieve what you want, than to build a custom drivebase. You should be able to get pretty close to any other team’s tank-drive style design with just the KoP. For instance, if I wanted 3310’s 3 mini-cim omni drive, I could upgrade my KoP drivebase to use omni wheels, swap in a 3 cim gearbox, choose an appropriate gear ratio, and swap the cims for minicims. If you mounted 3310’s superstructure to this modified KoPs drivebase, there are few people that would be able to tell the difference between the two from the stands.
The kitbot is fantastic for testing. If you have a wide kitbot and a narrow kitbot you’ve probably just covered 99% of your test cases. Add weight so they are at 120 pounds and they make excellent opponents for your backup drive team to drive and play D on your primary drive team.
Stick with the KOP chassis. Unless you have really good reason to switch you’ll be doing yourself a disservice.
This. Stick with the KOP chassis but save some duplicate parts by taking the voucher and only buying what you need. All parts of the KOP chassis are sold individually by AndyMark. We did this for several years. For us it’s usually $100 - $250 to get a few new rails and a fresh set of wheels. It varies based on what parts you do or do not modify in the last season.
Use the remaining voucher credit to get parts for manipulating the game piece. At most events it is what’s above the chassis that determines if you win.
I’ll pile on with my recommendation to keep the KoP chassis. With that budget, it makes sense to spend as much as you can on what goes on top of the chassis, so as little on the chassis itself. Making your own chassis at the same competitiveness as the KoP chassis will certainly cost more than the value of the AM voucher.
If you should use the KoP chassis and need space in the middle of the chassis for mechanisms, I designed flipped CIM and flipped miniCIM “KoP chassis upgrades” a while ago. You can probably ask a local team with machining resources to make the custom parts, and the rest of the COTS parts should be relatively cheap.
in 2017 we opted out the KOP and ended up using the money to buy the same wheels/hubs/pulleys/belts you get with KOP, i don’t think we will opt it out anymore.
it really depends on your teams inventory but i would recommend on keeping it because the hardware is usefull and it’s very nice to have a lame-easy to build-simple drive train for off-season projects or demonstrations.
who knows, maybe you will even decide to use it for the build season
Is this because you have less than $500 to spend, or because you can build the robot you want for that little?
It appears everyone here is assuming the former…but we try to do the latter. It’s like being in the real world, where you have to get the best bang for your buck.
You didn’t mention what your budget is.