pic: Another Beetleweight (Wasp)

Flash drive containing the files for Team USA was destroyed by ignorant classmate, so I decided to design a proper beetleweight this time. Wasp weighs in at 2.85lbs with battery and features a nasty 14" diameter overhead disk riding 1.0625" above the ground. Any questions/comments/concerns are much appreciated!


It’s super cool to see your designs progress. On this particular design, I’d be concerned about how you’re supporting your weapon shaft. It looks to be cantilevered off of the baseplate of your main frame? I’m concerned that it will flex just enough to drive your weapon disk into your frame, causing lots of explody fun.

Have you given any thought to purchasing one of the many beetleweight kits available? It’s honestly how I should have gotten into the sport. Most matches are won or lost on driving ability and a kit like the Botkits D2 is the perfect way for you to hone your skills. The D2 is a highly competitive bot out of box with a couple different wedge attachments and a zippy drive train. Combine that with some good driver practice and you’ll be a devastating threat to any bot at your local event.

I’m not a shill for Botkits or the D2 kit. In fact, a D2 wiped the floor with me at my last event.

Why reinvent the wheel when you can just buy it?

I’m not a battlebot expert, so I can’t comment on the design, but why didn’t you save Team USA on GrabCAD? It’s free and is very easy to use.

If it helps the bottom plate and the chassis are all one part (it’s abput 3/8" thick where the weapon shaft goes through). Any ideas for removing the explody-fun-time issue?

I can’t find any good pictures at the moment, but look around to see how other full body spinners do their bearing setup. You’re specifically looking for ones like Megabyte or Capt Shrederator whose disks pivot from the top of the frame as you’re trying to do.

You probably want to support that shaft with a frame attachment somewhere as close as possible to your weapon disk.

It’s hard to tell just by looking at it, but it looks like the weapon is heavier than the drive? Whichever component requires less torque to spin up(generally whichever is lighter) will spin up first. If your drive requires less torque to spin relative to your weapon, your drive is just going to spin out. And that’s all before your drivetrain loses traction - the only force preventing it from spinning relative to your weapon. I know the driver for Megabyte lurks around these parts. He could probably explain more than I ever could.

Can’t wait to see what you ultimately build, David. Good luck with your combat robot endeavors.

Well thank you! I checked and the weapon assembly is almost exactly 1.5lbs (its like 1.4875ish))

How does one begin to get involved in combat robotics like this? I’m interested but have no idea where to start looking for resources to get started.

Lots of resources for budding builders!

You can join us on the Combat Robotics group on Facebook or subscribe to the Battlebots subreddit among other social media groups. Everyone in the combat robotics community is very friendly and welcoming. Despite the competitive and violent nature of the sport, new builders are always welcome.

I see your team is located near Dallas. There’s actually an event going on December 15-16. Events are very spectator friendly. Stop by, watch some carnage, and talk to builders about how to get started!

As far as specific kits, I’ve linked to the Botkits D2 kit in a previous post in this thread. Like I said, that’s a fantastic way to enter the sport. The beetleweight /3lb class is one of the more popular and competitive classes, so finding events to compete at won’t be difficult.

Feel free to PM me if you have any specific questions. I’d be happy to help point anyone in the right direction.