Quote:
Originally Posted by kane
whenever i came on during like 4 days it was down so i was just wondering
getting bored again of the forum so prob gonna hide for another few months come back and see how boring it still is like iv just done lol
Printable View
Quote:
Originally Posted by kane
whenever i came on during like 4 days it was down so i was just wondering
getting bored again of the forum so prob gonna hide for another few months come back and see how boring it still is like iv just done lol
There can only be interference if the workings of a robot are disrupted. If people don't have an issue of disruption on 2.4GHz, the interference is eliminated. QEDQuote:
Originally Posted by k_c_r
Moving everything to 2.4GHz does create a more stable platform were the emphasis is on fighting and driving, not hoping your robot will run. That is an added bonus for the roboteers and Event Organizers alike. We (DRG and GRA) wil still allow for 40MHz to run but will also advise people to migrate to 2.4GHz whenever they can.
When are the minutes for the last GB meeting going to be published?
The minutes have been approved so they should be up within the next week
John
Many thanks :kiss:
Not a question to the FRA as such, more to the forum moderators, but if I want to post details for a robot event thats not FRA sanctioned (IE: an Antweight World Series), do I have to send the details via you (the moderators) to go into the Live Events section ? I posted the details in live event discussion this time, but just for future.
Only FRA approved event organisers can post in the Live Events section of the website. Please send me an email.
Hi All
Having been asked a specific question by a roboteer regarding the building of a walker, I had to go back to the build rules. All the build rules tell us are:
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.
This to me seems very vague so I thought I'd ask all of you the question:
What do consider the true definition of a walker?
I look forward to your thoughts
John
The difference is in the action of the foot or lower leg of the robot.
If you trace the movement is it mostly linear or circular in profile?
To give examples the Lego model has a crank to operate the leg. but the foot motion is a flattened ellipse not a circle,
but the second one Son of Whyachi the feet are in effect fitted directly to a crank.
http://www.youtube.com/watch?v=MqIehwrnF5E
I don't really know what I would consider to be the definition of a true walker, but I've always classed Anarchy as a walker in my mind. Even when the rules were changed so that it was classed as a shuffler, I never thought of it as that. The problem with that I guess, is that people will find ways to replicate Anarchy's leg mechanisms without using much weight and will then be able to fit much heavier weapons systems on to their double-the-weight-limit robots which in turn may prompt other people to complain about the classification of a walker.
But then this is just my opinion. I think it's difficult to fully classify as well. For example, I consider Clawed Hopper to NOT be a walker, but I believe that is similar to the mechanism used in DrillZilla (except more precise and much faster) which I originally DID class as a walker. So a lot of it could come down to personal opinion.
The best example of a walker that I can think of is Junior, built by the Plunderbird boys for Technogames. A lovely little machine to watch in action, and that is something I would definitely consider a walker.
Sorry, I know that's probably not much help :P
Its a very difficult one to decide. In the current rules there is no mention of not allowing shuffle bots let along defining what one is.
Well there are in effect two forms of walking robots
- machines that use pistons to copy the motion of muscles in the animal kingdom
- machines that use a rotational motion (electric motor) and convert it through a cam system to actuate a leg
I think that no one would argue that the use of pneumatic or hydraulic pistons should qualify for the extra weight.
The problem comes with the rotational conversion machines and defining how they must convert the motion. The reason for the problems is because they can be just as quick as a machine using wheels with very little problem.
How about the rule dictates that if a cam is used, then the motion must travel through a further two mechanisms after the cam before it is used to transfer the motion to the ground? Ie cam followed by two straight sections, one of which can contact the ground. No mechanism after the cam can convert the motion back to rotary motion either :)
I think that it should be that if the input to the system turns continuously it's a shuffler regardless of what mechanism you use to walk.
Hence, only linear actuator based mechanisms (pneumatic, hydraulic and electric) or non continuous rotary mechanisms (like standard servos with some programming to sequence them to walk) get the weight bonus.
that would certainly make judging the difference far easier
hiya,
I had a long... and i mean very long discussion ( argument ) with derek foxwell about this subject. But in the end, actually agreed with him in the end!!
Neoteric, my 24kg walker feather weight for Robot Wars extreme was only allowed once, but banned afterwards as it was classed as a shuffler. It had 16 legs and the motion was like a wheel as it had so many.
http://www.google.co.uk/imgres?imgurl=h ... x=82&ty=87
I think that it should be that if the input to the system turns continuously it's a shuffler regardless of what mechanism you use to walk.
I agree with this... any cam motion isnt a walker in my opinion, its a shuffler. The extra weight should be given for hydraulics, pneumatics, anything which doesnt use rotation motion.
JOhn
Roaming Robots
Quote:
Originally Posted by roamingrobots
WAT this makes know sense (but I know what u mean :D ) (the: I agree with him bit)
You've got to look at what a step is before you can define what a walker is.
In a step the foot is placed on the floor, lifted and then moved in a linear motion and then placed on the floor again.
Trying to define this in terms of wether it used hydraulics or pneumatics is wrong, it's the movement which counts. Craigs walky thing is very definitely a wallker and powered by an electric motor.
The rules do need to be deliberately vague to stop inventive people being penalised but good enough to make sure that the movement is incorporated into the design.
true but that's not a combat robot. Currently there aren't any active walkers so defining the rules will affect no machines in operation and only those made in the future. An extra 50 % for a shuffle bot is still a good 6.3kg. Not a weight to be sniffed at. I'm pretty sure you could make the walking mechanism using cams for only a couple kilo giving you a great deal more weight for the rest of the machine.
Plus there has to be an easy distinction to be made. Purely to keep everything civil and easy to determine at an event.
lol just realised my maths was off there but you get the point :rofl:
Just a few comments on a previous entry.
An extra 50 % for a shuffle bot is still a good 6.3kg. Not a weight to be sniffed at.
I may be wrong but I don't think there is any weight advantage for shuffle bots now. :shock:
I'm pretty sure you could make the walking mechanism using cams for only a couple kilo.
A reliable combat walker, I don't want to appear rude, but after making Pilgrim I would like to see that.
Walking.......What are the feet doing? I have said before the mechanism dose not really matter too much,
if you track the foot what shape is the trace, round or oval dose it have some flat portions etc.
we can have arguments about what is a true walker for ever.
I say vote
have examples of machines from U-Tube from feet stuck on the drive wheels (not a walker in my opinion) to Big Dog (A walker in anyone's book) The majority decision wins the day.
How many walkers are out there?
How many walkers are fighting out there?
How many walkers have ever won a combat competition?
How many moving parts in Pilgrim's leg mechanism?........................................ .................................................. Over 500!!!
Lets not kill the idea before anyone has tried to make something,
Everyone was worried about spinners, but in the UK champs it was the box type robot that won.
Lets keep the rules open as much as possible if walkers start winning everything (like flippers in the HW section) then lets think again.
Yup Craig you're right.Quote:
I may be wrong but I don't think there is any weight advantage for shuffle bots now.
This is the main problem though. If I turn up at an event with a machine that is in essence a cam with a leg attached (skuttle from technogames) am I going to get any weight advantage? I think most people would argue no but then where do we draw the line? Just to clarify I was meaning a very basic cam system for a few kilo. Anything with the complexity of the pilgrim would require a great deal more weight :)Quote:
A reliable combat walker, I don't want to appear rude, but after making Pilgrim I would like to see that.
Its very tricky to draw the line. Alan that walking cam mechanism looks good to me for being a walker. I know its good to have open rules however as you already know it requires a great deal of investment to produce a machine just to have it banned for its second event. I imagine Jonno was fuming and rightly so after putting in so much work.
I believe the foot / leg action meets the Walker criterion ...I would however get a ruling from the governing body before embarking on an an expensive build.
A walker is
1/ a machine that is supported by it's own legs and only it's legs 100% of the time including stopping and turning.
2/ The foot must move in a pattern that simulates a walking gate, (like a bird, horse, insect, spider or human etc) what is not allowed is a foot or leg that rotates around.
3/ shuffle type mechanisms are feet, pads, blocks or plates with no legs, run on a cam or crank systems, sometimes the feet do not leave the ground they do not replicate in any way, any natural animal type walking gate.
So in closing lets say a walker must have a pronounced obvious walking gate.
(this means the foot is placed on the ground the robot is propelled forward by the legs action,
the foot lifts of the ground is moved forward through the air and placed back on the ground completing the cycle.
Jonno have you any pictures of the walking mechanism that you had that was banned, I would like to see if my
definition would let this robot back in to play, or exclude it.
I think that it should be that if the input to the system turns continuously it's a shuffler regardless of what mechanism you use to walk.
If we use your criteria no rotational motive force at all, then I can't think of one UK robot that was a walker!
Craig does that mean the giant walking robot you brought to the uk champs is not a walker as that has an input to the system that turns continuously
I also would allow the walking mechanism that alan has drawn.
I think I misunderstand Jonno's statement/quote, so I will wait for his input, but it dose sound like that at first glance.
I have been thinking of how to use only linear actuators to make a walker, the cost, complexity and fragility of such a machine in the arena would make it a none starter.
http://i48.tinypic.com/16ablnb.jpg
The machine above looks great but did it ever fight? could it ever win?
http://home.pacbell.net/roninsfx/new...echadon4.0.jpg
This is another one that never won much but it did look good :mrgreen:
Hi All
Your input is fantastic, some of it getting very technical but at the end of the day what we are looking for is a simple definition of what is a walker. I am starting to think, but always open to suggestions, that if the foot makes a circular motion it is a shufflebot but if it makes an elliptical movement it should be a walker no matter what mechanism runs it.
We do have to come up with something that defines what a walker is without stiffling creativity and making easy for tech-checkers and the EO's to determine whether it is a walker or a shufflebot.
Keep it coming it's been a very interesting discussion so far.
John
to me a walker is something that has legs or so NOT WHEELS
thats it
In the new ruling will there be a weight allowance for shuffle bots john?
Any change to the weight ruling for shufflebots would have to go to the committee. What we're looking for here is clarification of the definition of a walker so that if anybody decides to build one they can do so & know it wont be classed as a shufflebot
I didn't start this topic with the aim of changing rules per se, I did so because I'd been approached by a team thinking about building a walker and they didn't want turn up to an event, have it classed as a shufflebot & then disqualified for being overweight
John
What did robotwars rules say? It would be nice to see a walker be competing well, something like mechadon in a featherweight would look awesome :proud:
I think a baby snake would look better. :DQuote:
Originally Posted by grant_ploughbot
Here's the RFL's definition.
Quote:
Non-wheeled: non-wheeled robots have no rolling elements in contact with the floor and no continuous rolling or cam operated motion in contact with the floor, either directly or via a linkage. Motion is €œcontinuous€ if continuous operation of the drive motor(s) produces continuous motion of the robot. Linear-actuated legs and novel non-wheeled drive systems may qualify for this bonus.
As far as Robot Wars stood on the walker issue, I'm not totally sure but I will endeavour to find out. Maybe Jonno could enlighten us as to Derek Foxwell's definition, as he appeared to make the decisions for Mentorn
John
are we not playing by our rules now ? its RR or RL or RC want or need ?Quote:
What did robotwars rules say?
and if we did we would have active weapons ;) lol
bearing in mind the issue of cost of building onlky to be disqualified etc which has been raised is it not sensible to put a proceedure in place where a mechanism design can be approved eg: three comitee members coming up with a unanamous decision or recommendations for modification or four out of five comitee members saying it's a walker.
John L - It's worth looking at what Robot Wars had as a rule because they have probably had more time, and more people to come up with something that works - If we find the rule and it sounds sensible and simple then it's worth using, if not then it might be worth adapting, or as you say make a whole new one.
http://members.toast.net/joerger/rules/RW7_rules.html
Quote:
2.1.2 Legged Robots ('Walkers') can weigh up to 200kgs/441lbs in the Heavyweight class. Walkers that employ a rotary camshaft to actuate feet will not qualify for the weight advantage (shufflebots). No walker must employ any device other than moveable legs to support its weight. No type of rolling or sliding mechanism will be allowed
i my book rules are for breaking ;)Quote:
If we find the rule and it sounds sensible and simple then it's worth using, if not then it might be worth adapting, or as you say make a whole new one.