Brand new and rare

After running Mecha Sombra at a few events, I'm really pleased I've managed to settle into the robot combat crowd. But I have a feeling that I now want to try something new. As much as I love my current bot, I want to do something more complex, not just as a challenge for myself but as a treat for audiences too.
I decided I wanted to make something which would be both entertaining to watch and unique, that needn't necessarily be hugely damaging. So after weeks of brainstorming, sketching and scouring the net for available components, I've decided to make a type of machine hardly ever seen nowadays; A walkerbot.

What I have in mind is something of a lightweight cross between Anarchy and Killertron. A well protected chain-driven leg system to drive it, and a counterweighted 180 degree motor-driven axe for a weapon.
I'm not necessarily worried about having a destructive or fast machine, just one that can hold it's own in non-spinner events (which are the only ones I attend at this point) without being utterly destroyed. All more fun for people watching!

Have decided on 2 x 350w scooter motors for the drive. They're powerful, easy to mount and compatible with technobots sprocket and chain systems. And although quite heavy, I can use them thanks to the extra weight allowance.

Concept art for the external design below. The idea behind the 2 large 'fins' on the top is to absorb impacts and to help the bot roll when self-righting. (sorry for the low quality image, I don't have any fancy art apps)
Attachment 5278

Danny, just re-read your first post. You're planning on using the Anarchy method of walking, yeah? If so, you won't have any extra weight allowance, that mechanism no longer fulfills the walker criteria.

"2.2 Legged Robots [Walkers] can weigh up to twice the specified weight in all classes. A walker must employ moveable legs to support its weight. Each leg must have at least 2 degrees of freedom. Robots with rolling or sliding mechanisms will not be classified as walkers."

What I planned was to have the legs 180 degrees out of phase with each other so that they met at the halfway point without the bodywork ever touching the ground. I'd always have 4 legs supporting the entire weight, I was only referring to Anarchy in terms of the way the legs move. Does it still not count?

2 degrees of freedom is two separate axis. up/down, forwards/backwards.

Oh, I see. I thought it meant 2 degrees as in the angle, I thought that seemed strange. So do the axis have to be independently controllable for it to count?

Yes, you need to be able to control each axis on each leg separately OR they muct be mechanically independent. I think the latter is a better way of saying it as most walking machines, like hexapods, have their movements pre-programmed and you can edit them mid fight, but if you needed or wanted to you could make each servo move separately, where as a cam/mechanically linked system is fixed and can only do 1 movement.

Ok, as it stands I have 2 options:
1. Try to create a much more complex walker than I intended, or
2. Simplify and reduce this design to bring it within the standard weight limit.

Personally, I'd prefer to take the second option. Like I originally said, I'm prepared to sacrifice some performance for entertainment's sake.

I think you will find that Anarchy does comply! This rule was present when Anarchy competed and was accepted by Mentorn who brought the rule in to remove robots like Drillzilla. Each leg is driven by two axis , one drive the leg up and down and the other forwards and back, OK this could be argued to be 1 DOF, depending on how picky you want to be. But each leg also had independent suspension allowing the leg to slide vertically to allow for floor, adding another DOF, that independent.
I believe the rules are very vague and open to interpretation, that said I don't think I will be bringing Anarchy back.

More likely something along the lines of the all the other slightly boring boxes, flippers and spinners. It hardly seems worth the effort of trying to make something different! But then that's possibly why Robot wars is no longer on TV!

Mike.

Team 101
Coming back soon!

Under the current rules this is a shuffle bot!
Total number of parts in the mechanism is unknown but exceeds 700. :)


https://www.youtube.com/watch?v=wf8FtpI3Eyo


best of luck with the project guys, looking forward to not being the only one with a walker at events.

Well that just proves that the interpretation of the rules is incorrect!
WALK
verb

gerund or present participle: walking

1.move at a regular pace by lifting and setting down each foot in turn, never having both feet off the ground at once.

The walking mechanism was sufficient to please the Guinness book of records, when they presented Scuttle with the world record for "fastest walking Robot" 2001!

As above the rules are there to stop the use of DrillZilla type systems that are nothing like that of Anarchy or Pilgrim!

I have to say I agree with Mike on this one, if it really is Mike. I looked back over the rules and nowhere was it specified that the up/down and forward/backward movement of the legs had to be independently controlled. If that is the case, I struggle to think of any competitor in UK robot wars history that would qualify today.

Well its not Mike Troll

If from this we can get a rule change to make "walkers" a less silly task, that would be great. That or fill in the grey for other forms of walker. I think a 25% or 33% weight advantage for shufflers is perfectly reasonable and does nothing but encourage diversity. Wiping them out completely is extreme. It's not like everyone has the ability to design and build a shuffle mechanism that can match wheels, and if they can, then well bloody done.

I can see the flaws in having a full 100% weight allowance for shufflers - you could probably attach a couple of legs to some wheels and then give yourself a shell spinner heavier than most robots are, whilst I do agree it encourages diversity in order to get that reward of extra weight, I think it'd be silly to give shufflers the same weight allowance as true walkers (the latter being as far as I'm aware significantly tougher to implement...) - As Ellis says, about 1/3rd would allow a featherweight shuffler to be about 18kg, and about 130kg for heavies which is enough to get some benefit through bigger weapons or whatever, but not so much that it's balance-breaking. Would still be cool as a demonstration though, even if it wasn't tournament legal, under the current rules... of course, you'd have to check with EOs first but still.

Technically Pilgrim is under the current set of rules a shuffle bot, I had tried for a long time to get a better definition of walker for combat applications but there are a number of people who wanted such guarantees that people would not get around any definition and make a robot that would disturb the status-quo. And suddenly everyone would loose to the insidious walkers! Like the first bit of War of the Worlds.

I have now given up on this. I hope you have better luck than I did. :)

I do think there's something to be said here. because the whole point of these events is to encourage participation from all levels of experience and expertise. But making the rules on walkers so restrictive means that only a professional could possibly have a chance at making one that would qualify for the extra weight allowance. Personally I think the extra allowance should depend upon the type of walking mechanism and it's complexity. I don't think it would be unreasonable to allow the following:
- Shufflebots and hoppers (e.g. Drillzilla, Clawed Hopper, RT-81) 25% extra
- Simple legged bots (e.g. Anarchy, Eleven, Black Widow, Pilgrim) 50% extra
- Fully independent walkers (e.g. Mechadon, Jim Struts) 100% extra

Anarchy weighed in at around 185Kg, I would not have got it a lot lighter. The problem is that wheels are very light and leave you with spare weight for armour and weapons. Anything else like legs or tracks just eats into your weapons budget. The other problem is given the work in building the legs and drive mechanism you need quite a lot of armour to protect the investment in time and money! I am still confident that the leg mechanism on Anarchy complies with the rules as written!


BTW Anarchy with the upgraded 2.7Kw motors (from Bosch 750w) was a lot faster than 5mph more like 15mph. The main reason Anarchy lost to Tornado was one of the of batteries stopped producing 12v, plus some very bad weapons control by me!

I think the issue is that not only would you need to be a professional to build one, but that the rules aren't immediately clear what qualifies as a walker. It does seem strange that Pilgrim using a Jansen walker linkage and Spiderbot using a Klaan walker linkage are classed as walkers everywhere except in combat robotics. Unless we want to continue with having events where all the robots look the same and have the same weaponry (which maybe some people do) we need to encourage builders to do something different and the likelihood is that that would need to come from changing the rules somehow, because the arenas are unlikely to change, and I would say that its best they don't. Particularly with the HWs it seems as if an optimum design has been achieved and now it's just a case of copying and changing the paint colour.

I know this is only a small group of people talking about this, but what would it take to try and get the rules changed? It sounds as though there's a pretty solid argument here that could really do with attending to.

I would certainly believe that if the public and other roboteers call it a walker, it's a walker.

Just stumbled across this thread. I'm BIG in favour of keeping the 2 independent DOF ruleset to get the full 100% weight limit increase. This is especially key in the featherweights. Putting 13.6kg machines against a 27.2kg machine is a huge mismatch especially when spinning weapons are brought into the equation.

I do have designs for a feather walker that fits the rule and with my 3D printing business taking off this year I plan to print out a few prototype designs to determine how feasible it is.

If people are interested in looking at alternate rules packages, here's the SPARC has an optional rule where non-wheeled robots that don't classify as true walkers (typically referred to as shufflers- See Son of Whyachi, Pitter Patter, etc...) get a 50% weight bonus. Things like the Jansen mechanism would classify as a shuffler in that system. That ruleset has been used at NERC events for quite a few years and it has worked quite well.

I would certainly agree that only true walkers should get the full extra weight allowance, but I maintain that other non-wheeled robots deserve some degree of extra weight rather than none at all. I'm completely behind the SPARC ruling, it sounds like a good compromise.