Using drill batteries in robots

Hi all,

could someone instructed me on how to covert drill batteries, to useable battteries in a robot?

thanks alex

Drill batteries come with a charger and a drill. If you are not taking the drill apart to make your drive train then get a discarded drill (tips are good), take it apart and you will find inside a clip that fits on the battery terminals. That way you can use your drill battery for your robot but it will still fit into your charger and you can use it in your drill too.
Drill batteries are fine for a first robot but battery packs designed for model cars and planes give better performance. But they cost more and require specialized chargers which you already have with your drill.

this may give you an idea, sorry the page is not as compleate as i would like. time is always of the essence

http://mysite.wanadoo-members.co.uk/thorak/football.htmhttp://mysite.wanadoo-members.co.uk/thorak/football.htm


--------------
James - thorak.co.uk

well we have so far taken the casing off, of the batteries and now dont know what to do (or didnt)

JOhn, we are going to use the motors for the drive system and the batteries for the power.

James i saw you disassembled the batteries completely, and then put them to gether how you prefered. what i wasnt clear on was how you then connected them to the chargers?

thanks alex

Cheap chineese drill batteries dont do very well in fetherweights:
http://www.bugs.nl/media/album/view.php?&path=L3J3L2N1aWprMjAwNS9ubC1jYXJsaWpuL0h QSU0xNzQ5LkpQRw==http://www.bugs.nl/media/album/view....bC1jYXJsaWpuL0 hQSU0xNzQ5LkpQRw==
Batterydrills have some nice current limiting to prevent these kinds of problems :)

But you can alway use them for a transmitter:
http://www.bugs.nl/media/album/view.php?&path=L3Byb2plY3RzL2Z6bjEvSU1HXzA2MzIuSlB Hhttp://www.bugs.nl/media/album/view....SU1HXzA2MzIuSl BH

i dissmantled the chargers, wrapping the circuit board up so it cant short. and connected them directly to the batteries via a two way switch. one way connects the batteries to the rest of the robot (on) the other switches to the charging circuit. the mains transformer just plug into the socket from the charger board. nice and simple.

Best not to take the batteries apart, leave them as is so you can fit them into the charger. Its true that cheap Chinese batteries are not ideal but they will certainly get you through a featherweight match and the price is right. If you put two of them in series and so overvolt your motors (provided your speed controllers are rated for the voltage)your robot will go like a bat out of hell.

with idk (the football robots) we didnt even have to over volt them we used 9.6V motors and batteries. we used the battery packs form both drill and remade them and had them in paralell with each other

so you just put them in seris when they are in the casing? and then charge them as if you using them for their main purose?

thanks alex

Yes, you can leave the battery packs untouched, charge them just as if they were going into a drill and then put them in series.

which is what i did in the r2d2 project. its fine as long as you dont want too much current. we left donut tyre marks on the kitchen floor with these batts running 12v drills on a 30kg robot, so there is performance to be had.

how would you connect the drill batteries while they are still in the cases?

take the connectors out of the drill case and use them

ok

thanks

i was wondering if some one could tell me, how many drill battery packs i should use for this set up:
4 12 v drill motors
they came with the batteries

but how many do i use?

thanks alex

I beleive that Push N Shove had a setup quite the same as that, and used 2 x 12v battery packs. One 12v pack per SIDE along with 1 Speed Controller per side.

Mr Stu

thanks

for talon i disgarded the drill batteries and went for one 3.3Ah sanyo pack

is it alright to chop the casing down a bit on the drill batteries?
i.e. keep the connector bit but cut the main housing off? it just the batteries wont fit otherwise in my robot

thanks alex

Yes.

On the underside of your battery pack you should find some screw heads. Undo those screws and the battery case will come apart. You might want to wind some tape around the now exposed batteries just to keep it all in one piece.

thanks

i have a question regarding the drill casing, the black bit of casing that has the chuck numbers on, i noticed it can move but can it be taken off without interfering with the gearing and other stuff?

thanks alex

Yep
that is the slip clutch ... a torque relief device that allows the drill to be used as a screwdriver.. the harder its tightened the more power gets transmitted to the screwdriver bit.. until it slips.. preventing the screwdriver bit from tearing up screw heads..

obviously as a drive system for a robot you dont want it to slip at all.. so either have it wound round to the drill setting.. OR
remove it, and lock the slip clutch.

to remove it you need to unscrew the Chuck, the screw unscrews the wrong way.. dont lose the screw !
then unscrew the 2 screws holding the slip clutch plate .. slide it off.. shake out ALL the ball bearings.. then get a 5mm bolt and gently wind it into one of the holes until the driveshaft doesnt slip..

what an appalling description.. Im sure someone else will do better

so this improves performance and reduces the size of the drill?

alex

Hehe, still not finished: http://www.micro-maul.co.uk/howto_drills.htmlhttp://www.micro-maul.co.uk/howto_drills.html

Yup, it will help if you do that aslong as youve got an appropriate way of locking the clutch with screws or through the way that the drill is mounted.

All the best

http://www.wa4dsy.net/robot/drillmaster/index.htmlhttp://www.wa4dsy.net/robot/drillmaster/index.html

Ignore the O Ring fix and use the screw method mentioned by Rob.

so with the drill batteries, i just need to wrap them up in tape and the are ok to use and charger? if i keep the connector on top

thanks alex

also i need to change the lay out of the cells, at the moment it is the usual drilll battery arrangment, 3,3,2 and 2 on top. but how do i detach one from another then reattach?

hope this is clear

thanks alex

Its best not to detatch them, But if you have to..

You wont be able to solder ontop of the cells very easily, its not adviseable either, If there are tags on the cells holding them together, cut them in half in the centre, you can solder onto the tags easyer then on the cells themselfs.

I Wouldnt advise it though. But if you have to, try avoiding heating up the cells as much as you can, when you re-join the packs, use a very hot iron and try and get it done quickly.

Could i cut in half and connect them together with wire and 2 connectors the half tag going into the connectors?

alex

Thats what i ment, yes.

I have encountered a problem, the tags that attach the cells together are arranged ib such a way that the shape the cells are in cant be altered, does this mean i have to do the cutting tag and reattach with connectors technique for every cell? or is there an easier way?

thanks alex

do you have any pictures? its more than likely that atleast half of the cells could be left as they are, and bend them into place, and cut/re-attach the other cells.

I havent any to hand but ill get some for tomorrow

thanks alex

Ive uploaded a picture on to my profile, i did have 3 suitable ones but i dont know how to put up all 3 at once

thanks alex

You could combine all 3 photos with Paint or a similar programme .
Instructions for Paint.
Open one photo with Paint .....then click image and reset attributes to 3 times the width shown.....then click on edit pick paste from ...and import/paste into position the other 2 photos......SAVE AS.

On the battery front what configuration would suit you?

either them all to be in one line or 2 lines of five, is this do able?

ill try the paint thing, and upload all the pics together

thanks alex

Is this do able ...short answer yes.
Its difficult to suggest the best way to reconfigure your pack without actually having it in front of me .... so ......Id suggest cutting the batteries into blocks of 4 or 2 and then resassemble into a pack.

(Message edited by woody on January 05, 2007)

Its a lot easier to resolder onto the cut tags than to try and solder wires (or battery bars) direct onto the batteries.. which takes a fair bit of heat...
just remember to make sure you solder back + to - and leave a terminal free at each end or things will get very very hot.