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there is no way a 1.1kg bottle will fit in a feather. 600g bottles are too big, as the robot has to be big enough to contain it, but we have to make do!
the main problem the designing of delta is making the robot small enough to contain the bottle.
my 1.1kg bottle for my middle weighs 2.1kg EMPTY, also its about 40cm long.
like stu says keep dreaming!
Arr - i knew it was over 2kg empty. Nice to confirm Alan, Thanks.
Not dissing you Ian etc - like everyone else, just warning you now before you go into a hyper. I do it, everyone does it. You go into some sort of hype what everyting will work, then you start to do it and thing - oh dear. If thats either putting it on CAD or making it hands on as a prototype.
Like Alan Said - even the 600g bottles are too big really. They can just fit in after a push and lot of stpid weight used to make the bot big etc.
Mr Stu
I dont mean to dis you guys and i totaly respect your opinion and respect yous (after all yous have built a working feather) but i think if you do use a 1.1kg co2 bottle you would be unstopable. It would give you litterally hundreds of flips before becoming empty.
Am I correct in thinking that at the end of a fight the 600g bottles are usually empty?
Thanks for that tip stu I did not know that that was the idea of the buffertank.
My thoughts are:
You could build a fully driving and controled base plate for about 1.5-2.5Kg(Bosch 35w Motors, Electrolise Controlers, 12v 2000mah Ni-mh).
You then start to add the chassis to support such a strong flipper which is another 2kg ish. Thats give or take 5kg.
That still leaves 7kg for Pneumatics. 2kg for the 1.1kg Bottle leaves 5kg which I am sure is possible (maybe not with much armour but hey hey)
Maybe I am way wrong and if so Please feel free to say not a hope but Like Henry Ford once said:
Whether you believe you can or you cant, you are right!
Regards
Ian Mc Donald
Ian, your rather gueshish weightcalculations arent bad, but you will run in the Roboteers axomia.
Everything is bigger than messured, weights more than weighted,and costs more.
No, a 1.1 kg CO2 bottle is fine in a middleweight or a low powered heavy, but for a feather its way oversized.
And for yours.. even idioticly totaly over the top too bloody BIG.
Calculate with Uncle Mario.
1 Kg of CO2 is 500 L gas on 1 bar(I know its more, but I use 500 kg to have some room and not to make the mistake like in the early days -overentousiastic positive calculations)
550L gas on board then.
A 63mm diameter 100mm stroke ram uses at 10 bar 3.1 L of gas. The mentioned double acting system uses about double(minus rodvolume)so 6l each stroke. 550/6=91 flips.Now I would say, 70 as a good compromise, due losses in all the parts.
5 minutes are 300 seconds. so every 4.3 seconds you can fire your ram, the complete fight.
Now, we go for a armheight of 30 cm
this system has then a 100 kg lifting capability
Now, we go for the hypothetical BIG BOY on the block, a HUGE FP system bore 70mm stroke 80mm Full pressure ram.(single acting)
600 Grams of CO2= 300L gas
Gasuse each stroke 15.4L
19 actions. So 15 actions(this will be more, due the fact the pressure drops as the system cools down, but with 2 tons on 50 bar,you can afford to lose some pressure-30 bar means this monster still has 1.1 tons)are a good budgetted thing.
300/15= 20 seconds. Every 20 seconds a flipping action ,capable to overpower a heavy.
Lifting capability on 30 cm 513 kg. -This means in featherweight norms about thesame power as Gravity has on the ram, not on the flipperedge.
So the size and volume of a 1.1 kg is even for a gasguzler in featherclass way overdone.
As for the I have 5kg to do this etc i did that, and i was in trouble with FlowRate being studpily over weight by about 2kg. But drastic actions have been done - so should be fine now.
I did your sums and i got about 5kg left over for - batteries, motors, chassis, armour, wiring, speedos. I foud out that my 2 x electronize speedos are about 400g for both. along with RX and team delta to swtich valve on/off - thats half a kg just for electronics. I only left about 200g for all my electtonics, how wrong was i.
Bosch 35 are about 550g each.
So 1.1kg for drive
1kg for Battery
and a structure to cope with a 80mm bore ram and 100mm stroke. Hmmm - unless you use thick ali or nromaly thickeness welded steel or thin ti - i cant see that happeneing.
as for the comment You have built bots, i havnt this is where im trying to help you. I have gone down this path with my pneumatics, done the same things as you. Oh i got this much for this, should be fine well it aint for my stuf, and if your sutff is even bigger, your gona find it EVEN harder. My rams are custom made - VERY light, the i use drill motors and Marios VERY LIGHT drive pod/gear boxes - and im still struggerling for weight.
And another thing - not to get personal or anything, just helping out - what about money Ian? Bosch 35 motors are about £55 each, elec speedos are £30/40 each, valves will be OVER £70, battery will be over £40. All the pneumatic parts like push fits etc all add up in price fast. High flow regulator - mega over £80 at least. Ram will be alot also unless you get that free somewherel.
Dont rely on oh i will get it sponcored either.
Do you have the means to fill your co2 bottle up? Is there somewhere in Ireland for you to fill ur co2 bottle up? Dont say ill find somewhere or theres this place i will ask - make sure your are sure.
Maybe I am way wrong and if so Please feel free to say not a hope but Like Henry Ford once said:
Whether you believe you can or you cant, you are right! Whatever - this is roboteering :proud:
Hope some of the above is helpful.
Mr Stu
Id have to say, it has mostly been verry entertaining :)
I have been thinking of a fether flipper among other things. But reading this I know competition is already fierce, maybe a little too fierce.
Its scary realy. Ill keep on dreaming then, shall I...
Dont keep dreaming- design and build!
How good a robot is on paper counts for very little in the heat of battle. Driving and tactics are everything. I would put my money on a simple, basic, low pressure system with a good design and good driver, against a wimba wamba elephant hurling FP feather any day of the week.
That said, stick a good driver with a wimba wamba elephant hurler, and your laughing:-)
2 years ago the thought of pneumatics scared the proverbial out of me, but having been playing with low pressure stuff a lot over the last year or so, and having someone like Mario to talk to, custom building a full pressure system has become do-able. Thats why I love robotwars- you learn new stuff! And so much of it! I cant think of any other engineering disciplin (for want of a better word) that teaches you both how to build a speed controller (or at least feel confident enough to start toying with the idea) and allows you to work with full pressure pneumatics, learn about manufacturing processes, everything from moments of inertia to knowing tricks for cutting polycarb and so on. I love it:-)
Random as the above may sound with relation to pneumatics, its really just saying that the best designs come through playing and faffing, or at least thats how i get most of my ideas.
I agree with stepan- entertaining and enlightening:-) Good conversations like this are top dog on forums, lets keep it up :D
Here Here.
Mr Stu
i have to say im starting to have doubts about my feather
weighing the stuff at malvern and having 7kg for armour and eletroncis i thought would be cool but you forget about all the little things like screws and conectors and things that add up.
i threw myself in the deep end with ants building a pneumatic flipper.i was pushing it with weight to get it in the limit and over the year and a half of fighting it i have got it lighter and lighter.
my feather is a scaled up version of the ant and im trying to keep at simple as possible but ive been finding its just not that easy!
and ian. i know how you can be. you get quite over ambitious about what you want to do. start simple and build on that. you robot is sounding way to heavy.
jus think about what your going into and take the advise from these people. mario stu eddy alan and stefan have all been in this game for a long time and no wat they are talkng about..
anyway good luck.
(heres a pic from a couple of months ago... argh these motors are gunna be heavy)
http://www.featherweights.org/featherweights/rebel_feather.jpghttp://www.featherweights.org/feathe...el_feather.jpg
Ive got about 1kgs worth of Bolts and Nuts and washers in FlowRate.
I didnt allow a full kg for stuff like that.
Mr Stu