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hi all
i am currently in the process of designing a new robot. it wont be anything exciting just a push bot. but i need suggestions for motors, i may go with 2 or 4 wheel drive unsure st the moment. drill motors are slightly to big and im working on a small budeget, upto £40 for a pair. so what to use?
if addiontal info is needed ill post later
thanks alex
Gold motors are about the best bet, £25 each.
speed 900 are better, just £20 each, will run from 9.6v up to 36v no problem.
Speed controllers to handle them are alot though.
Gold motors with the right gear ratio give good results.
not really, at 12v you can use the cheapo ones Leos importing from Asia, so a working motor/speedo for £35.
Alexander only has £40 guys...if the motors cost £50, and he has to add gearing hes stuffed..
the drill motors will be the cheapest route.. Alex are they too big in physical terms or in power rating for whatever speed control you plan to use?
if in physical terms, then maybe consider taking off the chuck and fixing the wheel direct to the spindle, which will make them shorter..
Or go for 2 wheel drive on a 4 wheel robot, and put the drive wheels on opposite angles..
so front right, and rear left.. this works fine, and means you can have a wheelbase width of around 200mmm with normal blue wheels (I have done this on a sumo bot)
If you want basic speed control aradilte a a couple of microswitches to either side of a cheap 3003 servo, so in the centre it switches neither, and at either extreme it switches one way or the other..
this set up will costs about £6 for the servo, and £2 for the switches for each side.. so £16 for control, add a couple of £12 drills, and you have all you need for £40, minus the radio gear.
i think i know why the drill motors are too big. :)
i suggest you follow Robs suggestion of one drill in each corner. It works great on little hitter/flipper.
Are you looking to have the wheels contained within the robot or are you gonna make wheel guards for it? (Im assuming this is for the metal chassis :))
If youre going for the wheel guard approach, then Id agree with the diagonal drive system mentioned with the drills. If youre wanting the wheels contained then possibly the only option due to the height of the chassis would be zeobot motors (then again, theyre ~£40 each rather than £40 for two).
width of around 200mmm
Is that 200 milli millimetres then :proud:
if you are putting wheel guards on, you have no problem. 4 drill motors fit in that chassis, with the wheels outside like king buxton. adding guards is then easy.
thanks for the suggests
i was just wondering if i was to use the drill motors in suggested arrangement, how would you keep the other two corners from touching the floor? BTUs?
its just ive never seen this done before.
thanksa alex
Im not ruling out the other suggestions, but where would these be purchased from?
the speed 900s
or the gold motors
thanks alex
You put a wheel on each corner, but only 2 are driven.
look at this here robot wot I built...
http://killer-carrot.blogspot.com/http://killer-carrot.blogspot.com/
it shows the layout of the wheels, and the attachment.. obviously this is a sumo bot, so its ok to use old bits of pneumatic pipe as axles.. I suggest for fighting at 12kg you use something a bit tougher.. but the principle is the same
http://www.technobots.co.ukwww.technobots.co.uk for the golds
http://www.sussex-model-centre.co.uk/shopexd.asp?id=1206http://www.sussex-model-centre.co.uk...xd.asp?id=1206 for speed 900s (although its probably worth asking at a few model shops see if you can get them cheaper)
ok thanks ill research all the suggestions
cheers alex
just a few of suggestions based on the chassis as it was when you got it....
1- golds are too big, youd need to increase the height. means modifying the chassis shape.
2- 900s, bigger than drill motors and you still need gearboxes, so youll need to make or buy a gearbox, and they stll wont fit inside the chassis without wheels outside.
3 - just use 4 cheap drill motors with external wheels, and add 10mm polycarb sides to enclose them. You will need to cut these polycarb bits, and some bolt on brackets, but thats easy enough. I recommend this option.
sorry to pinch this thread but i am looking at drive for a featherweight and i would like to buy either mini ev motors or hti motors the hti motors i would gear at around 1:1.5 and im not sure wat i would gear the mini ev motors to. would you agree with this or do you think that these motors will not be powerful enuf (i would go for golds but these work out cheaper even with postage from the states and i dont have the 50 pound for golds)
thanx,
josh
If you are still building this robot, email me and I will send you some pics of one that I built for my grandson using one of Jamess pay to drive shells. Using two cheap Do it All drills and the batteries.
Dave.
Pic now on profile.
it was nice to see good old toxic rebuilt as a fighting robot Dave. you did a great job.
Those speedos look familiar.
did toxic get used? excellent! hope the paint job stayed!
no, Dave repainted it. Shame, but i guess sicky green with carrot bits in it isnt to everyones taste :)
It did fight, and seemed to run really well.
Even survived the spinner!!!:-)
excellent. ye the original paint job wasnt... erm lets say average was it lol. looked great though! hope to see it at an event