Rules clarification on walkers?

[Metal Demons]

Okay... I have an idea in mind and want to know if it would count as a walker (and thereby be eligible for the 100% weight bonus).

Essentially, it's a vertical spinner with the disc support structure mounted on a vertical axle, enabling the disc to be angled to the left or right. A couple of cables connected between the disc supports and a motor acting as a servo would enable the disc angle to be changed. The effect would be, by changing the angle of the axis of rotation of the spinning disc, to lift swing each end of the robot forward alternately - therefore causing it to walk via gyroscopic precession. A movable foot on each end containing magnets (actuated by a large servo lifting it up and down) would allow an additional input for regulating the degree by which each end of the robot lifts up, in addition to providing extra traction when necessary.

(Okay, using movable magnetic feet rather than electromagnets is rule shaving, I'll grant - as electromagnets wouldn't satisfy the weight supported by movable feet part).

Basically, what I'm asking is this - would having the weight of the robot supported by movable feet count even though they're not actually causing the robot to move count?

[geoff]

Re: Rules clarification on walkers?

Build rules (section 2) refers...
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. Robots with rolling or sliding
mechanisms will not be classified as walkers.

To be honest I'm not sure that a device capable of gyroscopic progression (as you discribe it) would be classed a a 'true walker' in the spirit of 2.2 above. However before any determination could be made I would need to see a set of drawings or a working prototype.
I would love to see it in action as it sounds like an interesting engineering idea, regardless of wether it actually complies with the build rules for a walker or not!

Geoff Smith,
FRA acting safety officer.

[craig_colliass]

Re: Rules clarification on walkers?

Anything that complex probably would not win much even if it were twice the weight, but I would give it a go, anyone making a different type of robot gets my vote!
I am thinking this would be a feather weight robot so the weight allowed would be only 27.2Kg this is only a quarter of most HW flippers, I say lets have more different designs.

[Metal Demons]

Re: Rules clarification on walkers?

Anything that complex probably would not win much even if it were twice the weight, but I would give it a go, anyone making a different type of robot gets my vote!
I am thinking this would be a feather weight robot so the weight allowed would be only 27.2Kg this is only a quarter of most HW flippers, I say lets have more different designs.

Yep, would be a featherweight.

As for not winning much, it would have a ~11kg vertical disc (providing both motion and the weapon) against 13.6kg machines, so it would just be a matter of whether it could get a hit in I guess.

[craig_colliass]

Re: Rules clarification on walkers?

11Kg disc SWEET
I think with that you might stand a chance but the problem with this type of robot would be getting it around corners.
I with Tron and Seraphim would run away and try to tail gate your machine before it could turn round!
Also I would look up spinner rules about the size of disc! Keep it below 24 dia

[geoff]

Re: Rules clarification on walkers?

Hold on Craig, the 24 rule isn't a maximum size, it needs to be read in conjunction with the rest of section 10 of the build rules....


10. Rotational weapons or full body spinning robots
Full body spinning robots with an eccentric mass or €˜twackbots€™, are excepted from this
section unless they spin over 500 revolution per minute [RPM].
10.1.
The spinning element of any rotational weapon must spin down to a full stop in under 60
seconds.
10.2.
Rotational weapons exceeding any TWO of the three limits below must be submitted for
review and be pre approved by the event organiser
10.2.1.
The spinning element is more than 20% of the robots total weight. (This includes any
directly coupled motor components rotating on the same axis)
10.2.2.
The spinning element spins above 500 RPM
10.2.3.
The spinning element is greater than 24 inches in diameter.

As there are only 2 full class 2F arenas around at the moment (Robo Challange & the DRG) it would be up to these EOs to decide if they would allow it to run if the dia. exeeded 24 (Providing of course that it is classed as a walker under section 2 of the build rules in the first place!)

Geoff.

[craig_colliass]

Re: Rules clarification on walkers?

So 23.9Dia, 499rpm, 11Kg disc should be ok then
Some how I think the rpm might be more than 499,
this would mean the disc weight would have to be reduced to 5.44 kg :blush:
With EO's permit
But how many times have the discs on Fw spinners ever been weighed? is 360's disc 2.72Kg? :blush:

[Metal Demons]

Re: Rules clarification on walkers?

Just to clarify something... the OTHER walker idea I need to ask about.

I was also thinking of using a couple of large electromagnets mounted to rack and pinion actuators as feet, which would work by moving the foot forwards, turning the magnet on to pull the foot down and anchor it to the ground, pulling it back (thereby pulling the robot forward), turning the magnet off again, and repeating the cycle - which would serve to make the mechanically actuated movement involved far simpler and faster to execute (just back and forth) while providing extra traction above a normal walking setup. As the foot is actuated in two axes (horizontally by a motorised actuator and vertically by the magnetic setup), I see no reason why this wouldn't count as a walker...

*has a vague ambition to build a walking featherweight so he can stick a truly enormous spinning weapon on it*

[typhoon_driver]

Re: Rules clarification on walkers?

that wouldn't be a walker as the legs have to support the entire body weight and if i read your idea correctly you are planning to have the machine drag itself along.

With spinning weapons you don't have to bother throwing huge amounts of weight in there. An 11kg disc sounds awesome but you are going to have to manufacture it, build the supports strong enough to contain it and build the drive train which for something that big would be too much to fit into a featherweight.

Any walking spinner would have to have legs that were incredibly strong especially if the disc is vertical to be able to survive the reaction forces from collisions. I could see the entire mechanism shattering in a single hit.

[RogueTwoRobots]

Re: Rules clarification on walkers?

Oops, seems Drumroll exceeds two of those three specifications - a 4.2kg spinning mass (31% of total weight) spinning at more than 500rpm

Although I think that rule section is more to cater for extremely high-powered large spinners that might be a bit excessive of the norm??

Which leads to a possible situation regarding Nick's design. If it was built and was classified as a featherweight walker with its 11kg spinning disc, would the arenas be sufficient to contain it? Because even though a 2F arena is suitable for featherweight spinners and Nick's robot would fall into the featherweight category due to its 'walking' status, it would effectively be a lightweight robot by weight and if someone was to build a rolling lightweight spinner, they could also easily fit an 11kg disc to it. But under current circumstances a lightweight spinner would not be allowed to spin up/use its disc in a 2F rated arena, so would that apply to a featherweight walker with an 11kg disc too? Or would it only be allowed to compete in a full Class 2 rated arena?

[Metal Demons]

Re: Rules clarification on walkers?

that wouldn't be a walker as the legs have to support the entire body weight and if i read your idea correctly you are planning to have the machine drag itself along.

With spinning weapons you don't have to bother throwing huge amounts of weight in there. An 11kg disc sounds awesome but you are going to have to manufacture it, build the supports strong enough to contain it and build the drive train which for something that big would be too much to fit into a featherweight.

Any walking spinner would have to have legs that were incredibly strong especially if the disc is vertical to be able to survive the reaction forces from collisions. I could see the entire mechanism shattering in a single hit.

Both designs would move along on a couple of spring loaded pads (containing the magnets) which can be raised and lowered- when the disc hits its target the downward force would push the pads back into the body, thereby taking the impact on the bottom of the body.

[razerdave]

Re: Rules clarification on walkers?

Jamie: You only have to be under those limits to be in a class 3 arena. Anything higher goes into a class 2.

[typhoon_driver]

Re: Rules clarification on walkers?

if they move along on anything that is in constant contact with the ground then in my book they aren't walkers

[sarah]

Re: Rules clarification on walkers?

As far as walkers are concerned whether it would come under the build rules by moving it's legs by the gyroscopic effects of a spinning disc I don't know. Personally I don't see that this should be a problem but it would certainly be interesting to see. Uniqueness and diversity is always needed otherwise how do we progress

As far as the spinner part is concerned, size mass and speed are vital to what you are trying to do. For example Scorpion Evil has had vertical & horizontal bars, the vertical, because the bar was over 20% of the weight of the machine it meant the whole thing used to lift & twist when trying to turn, leaving it exceedingly vulnerable as it did so. Even Scorpion (HW) with 10% of it's weight in the disc was enough to affect movement severely but we were talking a 400mm diameter disc running at over 5,000 rpm. Even Scorpion's disc would come to a stop (when buried in something else )

Sounds like it could be a good fun idea. Good Luck

John
Scorpion Builder

[Metal Demons]

Re: Rules clarification on walkers?

I'm leaning towards option 2 at the moment - electromagnet feet moved front to back by a lead screw actuator. The trick would be that each foot is mounted through a flexible plate to the actuator, so has a few mm of up and down travel - so when the magnet's on, the foot is pulled down against the ground, and lifts up very slightly when it isn't. The base of the robot never contacts the ground, as while one foot is being moved back into position for another stroke the other's magnet is still enabled and keeps it in contact with the ground - the robot's kept level on that foot by a combination of the downforce from it (as the magnet is touching the ground by then and exerting its full ~200kg) and, guess what...

...Gyroscopic reaction, this one's a horizontal spinner... the gyroscopic force here acts to keep it flat to the ground.

I'm just trying to work out how to do a walking mechanism which would actually have a chance of standing up to combat here, as clearly a spinner 360 would just chop through the legs of a normal legged robot - something smarter has to be done. I think using the gyroscopic effect of a spinning weapon has to be a key here, along the lines of a little walking toy I saw a few weeks back which gave me the whole idea: it was a little toy robot which walked while stabilised by a flywheel inside the body.