Rotational weapons limits - Do they exist and what are they?

Hi all,

I'm new on here, but have been working with emisnug (Rob Keyes) who I think has posted several times on here about questions regarding our build.

I am well aware that the answer to my question is going to be variable based on event organiser, however, I'm going to ask it anyway:

1) Is there a definitive ruling on maximum tip speed or maximum energy for rotational weapons?

I'm fairly confident there's no clearly defined limit in any rulebooks I've seen so far. It all seems to be "contact the event organiser". Given that Rob, myself and Ali (Team ARC) are threatening to apply for any future series of Robot Wars, plus potentially some of the Extreme Robots events, I am quite keen to get a definition (or set of definitions) once and for all. So far, we've had no reply from Mentorn to this question (over a series of emails).

2) Does anyone have any definitive answer on what the limits are for Robot Wars?

One of the guys from Nuts took the time to suggest on Reddit that he remembered it being ~250mph for Robot Wars, but this was a purely from memory answer. Thankfully, Jamie from PP3D sent me over here to get a proper answer.

Rob and I have just spent hours getting things down to a slightly more sensible tip speed (around the 250mph mark - down from 370!!!), but before we actually send everything off to our friends in machine shops, etc, I'd quite like to know that what we're building isn't over any restrictions. We've done the maths on Carbide's weapon based on the stats from last series, and came out with about 230mph, and we're fairly sure that machine is very close to any limits. I will admit it's a beautiful piece of engineering though - one I'd quite like to keep our robot as far away from as possible... for now!

Any and all input appreciated.

Thanks
- Chris

Chris you will not in any likelihood get a definitive value that you can't go above. Rather if you send what you are planning to the guys at Robochallenge they will be able to advise either way. The reason you won't get an actual figure to work form is that there was a lot of expensive real world testing that had to be carried out smashing up sheets of polycarb to confirm what the theory said. Essentially the max figure is a secret. Frustrating in some regards but at the same time if you'd paid cash to find it out then you aren't going to want to share it with the world. Especially with battlebots in the US and other event organisers kicking around.

So in short, drop the guys at robochallenge an email with the details of your design and they will let you know if it would be ok.

Thanks Gary,

I kinda feared that was the situation. I'm well aware that a lot of money has been spent smashing stuff up just to prove the theory and I can see why that's an issue from actively releasing the numbers. I did drop them an email early up this morning after Jamie's reply on Reddit - but at that point it wasn't clear that I wasn't going to get an answer to my questions because of this air of secrecy over these magic numbers.

The bit that's slightly disappointing, I guess, is that we send in the design and it's going to be a "yay" or "nay" answer - and if the answer's "no", we'll need to redesign downwards - but we won't necessarily know how much by. I can just see this turning into a very lengthy guessing game for us - and probably take up more time than the guys at Robo Challenge want to spend on it.

Well if it helps, I may or may not have run a weapon recently at 230mph theoretical speed in an arena somewhere.

Thanks Gary - I think I know what you're saying. I think I may have been there too.....

234mph Gary :-)

Within engineering tolerances ;)