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Hi, im wondering if its possible to use windshield wiper motors, when you remove the worm gear sistem and put a chain sprocket on them -chain drive.
These motors should be quite slow, but i dont know anything about the power.
Is it worth a try? I have lots of them and im on really low budget.
By the way, i made one motor, it looks like a real thing ! :proud:
Going to make some more and test them out.
http://img14.imageshack.us/img14/2923/asjad.jpg
you could but you would have to find a sprocket small enough , and you would almost certainly have to weld it.
you say you r on a buget just use drill motors lighter and maybe cheaper all you have to do is put a wheel on them see other posts about that or email the coppers :)
why e-mail the coppers?
why involve the police John? :mrgreen:
i have some used but perfectly fine 'blue' wheels which are made by robo challenge they just screw right onto the drill
interested????
(btw drill motors much easier :talker: )
clive hmm jsut a typo i tink
Freudian slip more like :wink:
jsut a typo :rofl:
Mart, if the windscreen motors have gearboxes on them you could try attaching a wheel directly to the shaft. You would get a very slow robot with the sort of windscreen motor/gearbox combos I am used to but you could speed it up a bit with bigger wheels and by overvolting the motor. It's not ideal but it might be the way to go if you have severe budget constraints.
Ive tried attaching them directly to the wheel, but it was too slow for me.
Motors w.o. the worm gear stuff would be a completely bad idea?
If you just attach a wheel directly to the motor it will spin very fast but won't have much torque and so will stall when you put a load on it [like trying to drive a robot]. If you double the voltage to your windscreen motors they will run twice as fast and develop 4 times as much power. That will heat them up but they should last for the five minutes of a robot fight and give you a slow machine but one with lots of pushing power. Another approach is to make a gear or gear/chain reduction for your motors so that they can run at full speed but the output from your reduction unit is much lower speed and has much more torque. That might be harder though. As others have said, drill motors solve these problems because they have gear reduction units built in.
Do you have anyone else to fight in your part of the world?
if your using windscreen wiper motors , rexes robot guide is a great starting point ,
heres the link :) http://rrc.dannysrobots.co.uk/
Oh, ofcourse i would make reduction if i would use motors without worm gears! I just want to know if anyone had done same thing. I dont know if these motors are efficent for their size and weight. But i dont know how big? reduction i should make.
Somewhy the drill motors seem weak and small for me, for a fw (2 motors).
Another chance is to gear up the original worm geared motors, maybe 4:1 would be fast enough for a 100mm wheel?
I know all about the rex´s competition! :lol:
There are some events held in Finland.
oh sorry :lol:
Hi Mart,
It is certainly an option to use just the motor part of the windscreen wiper motor; I know of only one person who has tried it but didn't use it for anything more than one competition I don't think?? (help me out here Gary :lol:)
I chose to try this method too and got as far as removing the gearbox, with the plan being to use a small gear sprocket on the motor and a larger one on the wheel. I was aiming for around a 3:1 reduction but I never did use the motor for two main reasons;
1. It seemed underpowered so I wanted to get a more powerful motor
2. With the gearbox cut off there was no easy way of mounting it
I read that you are unsure about the strength and power of drill motors being suited to a featherweight. From my experience, a standard pair of drill motors have never really struggled to move a featherweight around the arena, they can usually cope. Obviously if you want more power in your drive, you could have four or more drill motors.
The other option if you're still not keen on drills is to go for the popular 'gold' motors (very similar in size to wiper motors but more powerful) or Speed 900 electric boat motors perhaps. Both would require your own gearing system but you seem to be happy to go down that route as you have planned to do so with your windscreen wiper motors.
Best of luck :)
Thanks, but the motor has 2 speeds. Is the slower one more powerful too? (mounting doesn´t look difficult for me, i think :lol: )
No reason not to gear up. Might be easier.
Design mustn´t be very simple, because im only new to combat robots. I have been messing around with mechanics quite a bit.
But what do you people think about gearing up the windshield wiper motors? How big would the gearing have to be for a 100mm wheel for a normal speed??? 1:3, 1:4, 1:5, 1:6 ?
Maybe i wrote the gearing wrong. Should be written like that, i think.. 6:1 5:1 4:1 3:1 -for lower speed on motor and higher on wheels.
i can see your logic in using just the motor part of a windscreen wiper motor , but really , your not going to get much better than the gearing it comes with , as said before, its going to very hard to mount , and other better , and possibly cheaper motors are available.
Ive never personally used them , but they look like they should be perfect for what you need
http://www.technobots.co.uk/acatalog/On ... rs_76.html
1st and 2nd one :)
Sorry, i didnt write enough. I meant gearing up COMPLETE wiper motors with reduction.
why would you wan to do that lol , the power / speed ratio is almost perfect for a FW as is , they are a bit slow in my experience , but with wheels bigger than 150 mm , they are really quite fast , the gearing would be very minimal to speed them up enough , so IMHO , i think you should just use them as is . That was ment in the nicest way possible and im sorry if it dosent seem like that :).
Ive tested these motors for a direct drive bot, but they were verrrrry slow for me.(0,5 ms or something like that :crazy: ) And i need speed, beacause im going to make a lifter.
My bot´s chassy is made for 100mm wheels.
if the spaces for the motors are too small for drill motors , then all i can suggest is overvolting them :( . sorry i cant be of more help.
Ok, i´ll just build the bot and post some pics of the gearing. :proud:
If you are using 100mm wheels, I would recommend using a 2:1 ratio (or 1:2 ratio, whichever way round it goes :)). So having, for example, a 40 tooth pulley or sprocket on your wiper motor output shaft and a 20 tooth pulley or sprocket on your wheel will give the equivalent of having a 200mm wheel attaching straight on to the wiper motor. If you're running on 24V this will be fast enough to have a competitive robot but one that is also controllable.
My old robot that used windscreen wiper motors had 178mm wheels (lawnmower replacement wheels from a DIY shop) and seemed only moderate in speed, but once I replaced the second-hand batteries with new ones, it was surprisingly nippy. So having a 1:2 ratio on 100mm wheels should provide a very decent speed.
Don't bother trying to build a new gearbox for a wiper motor. It was originally designed and built with the gearbox attached in mind for its application.
You will encounter several problems. The motor shaft will have a worm machined into it. You can either file this down to a small shaft or try and attach something to it as it is. Both methods will break in the arena and won't be reliable.
When you remove the gearbox, you remove the motor mounts. Trying to build a mount to hold them is a pain.
Wiper motors are underpowered more so than drill motors for featherweights. If you want to use a motor that size then use gold motors with a custom gearbox arrangement. More power and similar pricing.
My overall advice is to throw wiper motors on ebay and use the cash on robots.
i dont think he wnats to remove the wiper motor gearbox , just add a small chain reducton after that to make it a bit faster
Yep, that is my plan. 4/1 reduction. I hope it will be fast and powerful enough.
certainly be fast , but im not sure it will be very powerfull . have you got any pics of your setup? :)
Im building my setup at the moment! :proud: I´ll get four 05B (what ever it means) chain sprockets tomorrow morning and going to make the 4wd system work. Then im going to get some sprockets for the gearing between motors and wheels.
What do you people think about gearing? 4:1 or 3:1 (100mm wheels)
Personally, I would opt for a 1:3 gear ratio. 1:4 would give you a very fast top speed but your ability to control the robot accurately could be compromised. With that much of a gear ratio you're likely also to lose a lot of the torque from the wiper motor; I couldn't say for sure but the chances are you'd go to ram another robot and you would be struggling to applying any pushing force.
1:3 would still give you plenty of speed in an arena but would provide you with more available torque, so it would be my choice
I also thought that 3:1 would be better , im probably going for that too.
How many amps these motors take i have one mamba maxx speed controller, but would it be enogh for 2 motors?
Maybe i can do some testing by putting a like 50 amp fuse between the ESC and motors. If it burns, i´ll put a bigger one, so i can see how many amps it takes. I have a no idea where to get ampmeter. (im going to have a switch steering)
for the short time when i used wiper motors in my FW (i use drill motors now) a 15 A cotinous and 100 A peak speedo was fine , never mesured the amps being pulled , but the thing barely got warm
Hi, did some testing today and found out that 3/1 is quite slow on 12 v, but it will do it. But the problem is, that i dont know how good she system will be, if i woult put a 34mm sprockets to the wheel shafts and 100mm sprockets to the motors, i dont want to use many gears because i cant get all sizes.Going to the store tomorrow and look what they have.
so if I'm reading this right, you are taking a wiper motor which gears itself down only to gear it up again?
Scrap them and use drill motors or similar. You are going to spend 3 times the cash and time on those wiper motors