Fenrir256
(Joe Brown (Not the Joe Brown you're looking for))
1
Hi All,
Long time follower, first time poster and builder. I’ve been following and spectating for a while now watching BBB and NHRL events online (Trying to get to a BBB event in person as soon as possible just trying to fit it around crazy work commitments) and have finally decided to start committing to trying to build a bot.
So far I have been messing around with a few designs in CAD I’ve got a couple of ants and beetles in the works. After many, many redesigns I’ve final reached a point were I feel I can throw the first out to you all in the community and get some thoughs.
So here we are initial cad for a vert spinner with the working name of P.I.T.A. (TBC)
So ideas and specs behind this one are.
A Peter Bar style inspired dual blade asymetric spinner with blades of 6mm Hardox and driven by a 2814 T-motor outrunner.
Brushless 1806 based brive system, with the plan to run on Unmanned Tech’s Chaos ESC (I’d be interested to know if anyone has any experience with these?).
HDPE main chassis and TPU outer armour package and an as yet to be finalised wedge on the front potentially titanium but TBC.
And finally running a GNB 3s 850 HV LIPO to power the whole thing.
I’m looking forward to seeing how this and a few other designs I’ve got in the work progress and will of course provide updates as they do. Not sure if P.I.T.A. will be the first bot built as I’m also working on a beetle flipper too which will feature on this thread once its had a few design changes, but hopefully I’ll be able to get a bot to events in the not to distant future.
Thanks for reading and I’m totally up for answering any questions anyone has.
id be slightly worried about it getting caught on its side and the armour not allowing the wheel to touch the floor in that positions but only one way to find out i guess
whats your weapon stack-up like? looks like a tpu core/pulley
1 Like
Fenrir256
(Joe Brown (Not the Joe Brown you're looking for))
6
Yeah that has been one of my concern with getting stuck in certain positions and ground clerance (seems a classic theme). I’m planning to print a temp build out of PLA to see about fitment and these kind of thing before commiting to the final design fully. You know done loads of redisigns so far, few more wont hurt.
Yes you’ve hit the nail on the head with the weapon stack, this is where the inspiration from the Peter Bar kit has come in. TPU core sandwiched to the blade using hex standoffs. Will run on a shoulder bolt dead shaft with the needle bearings also sandwiched in the stack.
Fenrir256
(Joe Brown (Not the Joe Brown you're looking for))
7
Well finally had some time today while sitting on a train to sort out the last little bits of this current design, the big one being a front wedge. Currently designed out of 2mm titanium, with the offset bolt holes in it just allowing for a slightly cleaner mounting method.
This brings me really to the point with this design where I just need to start making and see if it works. Hopefuly this will be over this summer when I’ve got a bit more time away for work and back home. Might have to work on my ant design in the meantime.
Fenrir256
(Joe Brown (Not the Joe Brown you're looking for))
8
So not quite a year after throwing out to the world my initial ideas for P.I.T.A. and a very busy year working. I’ve finally have a update and a complete redesign. Guess this is what happen when you work away and no access to physically build.
A lot of this redesign was infuenced by a small test build i did last year which very quickly reveled, so less desirable design flaws, which hopefully have been rectified with this update. So here it is V3 of P.I.T.A.
I am planning to start test building parts of this in the next couple of weeks and see if this updated design holds together as an actual build.
2 Likes
Fenrir256
(Joe Brown (Not the Joe Brown you're looking for))
9
So a bit of printing and assembly later, V3 of PITA is actually a thing. Best part is other than a couple of small quailty of life and fitment changes as a whole the bot is working.
Selective photo angles as I’m still printing TPU Armour (Prusa Mini not the fastest with TPU but gets the job done).
Have had a great time with the wheels super PLA Hubs overcast in 40a polyurethane in a 4 part mold. Have had experience casting for work so was fun to apply that the this.
Mold for reference this is going to get a redesign again so I can injection cast them in the future for a better finish.
And finally here is the video of the first weapon test (obviously performed remotly and safely), The video shows the PLA mock up disk at around 50% throttle. The motor for the weapon has been a big change is this itteration changing to at Repeat Robotics 2836. Thanks @Joe for stocking them the motor has been great.
Next steps for this are to look into getting final weapon blade cut in Hadox (looking to get a quote from Lasered or Hawkshead Metal), work out milling parts in HDPE (CNC project is in the works) and yeah just run it around a bit for a shake down and see what happens.
Hopefully get this out to an event soon work allowing.
