Conundrum Mk1r2 - Team Robotic Death

[robotic_ants]

Watch this space, hoping to come back bigger and better.. well only if we can get the maooosive cnc mill working :twisted:

Will be going back to the orignal design but with a more powerful punch.

[robotic_ants]

Re: Conundrum Mk1r2 - Team Robotic Death

Right pretty much got the stats in my head. Could not get the mill working yesterday but when we do I might be able to take requests for parts but that's just an idea at the moment could be a year off.

Also can someone point me in the direction for the latest rules, and what are the current opinions on lipo? are they allowed and what are the limitations. I would like to use a decent brushless system but A123 won't suit my application.

[RogueTwoRobots]

Re: Conundrum Mk1r2 - Team Robotic Death

Was going to link you to the rules page on the main FRA site but having read them, they haven't been updated since June 21st apparently (although they may currently be getting re-written to incorporate recent changes). The main thing missing is that HWs now need to be on 2.4GHz and FWs have to be on 2.4GHz from 1st January 2011.

Lipos are currently allowed in feathers with rules such as 2mm minimum thickness baseplate, charging box for them, bag of salt (I think?) handy incase of fire etc. I'm not too clued up on them though. Grant, Dave M or Kenny could probably enlighten you more on that.

Nice to see you coming back into it. Haven't met you before but pictures of your robots helped me quite a bit when I first started designing my drumbot. Good luck with the build

[xtreme]

Re: Conundrum Mk1r2 - Team Robotic Death

Have the lipo contained in a secure box inside the robot. You cant just cable tie them down or strap them down. Always charge them in a lipo sack. Have a container of salt with enough salt to cover the entire lipo incase of an accident.

[robotic_ants]

Re: Conundrum Mk1r2 - Team Robotic Death

Well I will be needing a new tx anyway so 2.4GHz it is, anyone recomend which to go for either a Spectrum or another brand with 2.4GHz module?

As for LiPo i've really been in touch american bot builders and seen their rules as they are more common over there than the UK. They seem to be ok with them, charging them in LiPo sacks and making sure they have the correct fire fighting equiptment and thats it.

[xtreme]

Re: Conundrum Mk1r2 - Team Robotic Death

Spektrum

[robotic_ants]

Re: Conundrum Mk1r2 - Team Robotic Death

Have a container of salt with enough salt to cover the entire lipo incase of an accident.

My understanding is that for a fire you require either sand or a dry powder extinguisher to control the flames. But a damaged cell will require being submerged in salt water rather than just salt, as the water will flow where the salt on it's own cannot reach.

[Mouldy]

Re: Conundrum Mk1r2 - Team Robotic Death

Jamies pretty much got it right.

Salt water is better then just plain salt if they go up,
Charge them in a lipo sack
Id suggest always balance charging them- its not a rule but its not alot of effort to do
2mm base in the robot
battery box is best- foam lined
as with anything make sure its all insulated
dont charge/ discharge above or below manufacturers spec
put a fuse inline with the lipo thats rated below its max discharge rate- (if your lipo can give 125amp put a 100amp fuse inline)
Low voltage cut off - (abit of an undecided rule at the moment as aparently there hard to find-360 has them built into the esc's)
When your done with the lipo and you want to bin it fully discharge it and pierce it, then place it in salt water.
..theres probably somthing ive forgotten, im tierd.

[joey_picus]

Re: Conundrum Mk1r2 - Team Robotic Death

I was told the low voltage cut off was more of a 'nice if you have one' than an actual requirement, I'm using one on the featherweight drive but can't seem to find any weapon switches that have them built in.

[robotic_ants]

Re: Conundrum Mk1r2 - Team Robotic Death

The plans are to have them in a vented hard case anyway to protect the other components more than anything incase of an incident. Does a 2mm thick cardboard base plate count?

The design is going to be similar to the first MDF version of Conundrum, two main side rails slightly different design but much lower. Joined by cross members which will support the components, i'm thinking of either using 10-12mm Nylon 66 or pocketed aluminium for these. Then alittle armour on the outside to protect the wheels.

I'm alittle undecided on what to make the drum out off, until I get some parts together I won't know what weight I will have to play with but i'm thinking about something custom made.

Battery may be LiPo just for the weight saving, as I believe A123 are only really good for a current burst of 138A which my system my exceed at some point. To make sure the brushless is as efficient as possible I need to get a pack which will be able to cope and not limit the performance.

Drive motors are a conundrum at the moment as I need something like a drill motor but capable of handling high voltages which are reliable, gear box's will be custom machined like Conundrum Mk2's. Drive system isn't really planned out just the frame and weapon.

[psycho_fling]

Re: Conundrum Mk1r2 - Team Robotic Death

hi

i not sure a cardboard base would be suitable in any robot-it's hard to sense sarcasm on a forum post so sorry if you meant it as a funny comment and i'm missing it

i think the 2mm base has to metal nothing else- definitely not cardboard

speed 900's with some good gearboxes on can cope fine with high voltages

[RogueTwoRobots]

Re: Conundrum Mk1r2 - Team Robotic Death

i not sure a cardboard base would be suitable in any robot-it's hard to sense sarcasm on a forum post so sorry if you meant it as a funny comment and i'm missing it

Yeah I think Chris exhibited the classic signs of sarcasm in his post

Imagine a brushless drum fw, the amount of shocks going through the chassis and then picture a 2mm cardboard base on that. The words epic and fail would spring to mind in that case :P

To be fair, we didn't actually say what the material for the base was, so yeah its a 2mm minimum thickness metal baseplate

[Mouldy]

Re: Conundrum Mk1r2 - Team Robotic Death

I would of thought it was painfully obvious but then again i suppose things should be made idiot proof.

cardboard + lipo fire = bad idea.

[robotic_ants]

Re: Conundrum Mk1r2 - Team Robotic Death

Well if I could not use cardboard I was going to think about asbestos board about 5mm thick.. but since you say it's got to be metal then it'll be around 4mm steel/ali/hardox or similar.

Asbestos board + lipo fire = really bad idea! :twisted:

On Jamie's point the chassis is the main structural element, the way it's being designed the top and bottom plates won't provide any support or have anything mounted to them. Just there purely to stop people poking my expensive bits with an axe. Should be a long way away from epic fail.

As for drive motors I think the Speed 900 is out of the question because of shear weight alone although it should run 40v. I'm looking at a Thunder Power 8S pack so i'll be running around 29.6v unless I use a 24v motor and set the controller trims, think i've heard of people doing this before. How well does it work?

[typhoon_driver]

Re: Conundrum Mk1r2 - Team Robotic Death

Setting travel limits on the transmitter works well. Did it on hornet recently. I was using an 8 cell pack of A123s but my drills were only of the 12v mark or thereabouts so I ran them at 50% and they handled it fine.