Flipper (pneumatic) VS Lifter (electric)

[billy breach]

Re: Flipper (pneumatic) VS Lifter (electric)

I have a spare 14.4v dewalt xrp drill lying around so it'll be it....and boasting lol.

[ewan]

Re: Flipper (pneumatic) VS Lifter (electric)

As Gary said you should have more than enough torque for lifting be it a cheap argos drill or a dewalt, what you might want to look as is increasing the potential speed of your actuator though - obviously the faster the motor rotates the faster it will lift but also the larger the thread pitch (e.g. 12mm thread has larger pitch than 10mm). Also bringing the point the threaded rod/actuator meets the lifting arm closer to the pivot point (and adding an intermediate linkage to increase potential movement arc) are things to think about!

[typhoon_driver]

Re: Flipper (pneumatic) VS Lifter (electric)

If you were after a threaded rod with a high pitch and good power transfer then you could even look at using ball screws,

http://www.ebay.co.uk/itm/Machined-Ball ... 1c1c922830

These are using in computer controlled mills and lathes to control the axis. Precise and a 5mm pitch would be very useful but the price reflects the machining precision you get with them

[billy breach]

Re: Flipper (pneumatic) VS Lifter (electric)

Those ball screw things look good. Would a 5mm pitch be a good enough pitch to make the lifter fast? Ie. So I it would take less turns to travel the distance?

[RogueTwoRobots]

Re: Flipper (pneumatic) VS Lifter (electric)

Yeah with a larger pitch your lifter would move further for the same amount of turns as a thread with a finer pitch. A 5mm pitch would most likely be fine - even the pitch of scissor jack threaded rods, while less than 5mm, are larger than standard M10 or M12 threaded rod:

[attachment=0:3dxp1kyd]k3_build (36).JPG[/attachment:3dxp1kyd]

Not the clearest of pictures but you can see the threads are more spaced out compared with standard rod; this is one reason Kaizer's lifter has a good speed. The threads are also thicker and more durable, and the threads on a machine ball screw would be even more so.

[typhoon_driver]

Re: Flipper (pneumatic) VS Lifter (electric)

I would start out with a regular threaded rod. It's cheap and simple to implement. Get used to building a bot and get it into the arena. Then look on ball screws or an acme thread as an upgrade later down the line. Believe me, you will have enough worries getting a robot running in the arena!

For reference, say an M12 threaded rod has a pitch of 1mm. It means that for every one rotation of the rod, the nut will move 1mm along. A 5mm pitch will mean that the nut moves 5mm along for every rotation. But there is a cost, it does mean that the motor will have to work harder to lift the same amount of weight at the end of the arm.

If you do get around to using ball screws then I would recommend covering the rod in an extending metal coil and don't open up the nut, ball screws work in a very interesting way by using small ball bearings to travel along the rod. They are a pain to get back together correctly if you take them to bits.

[billy breach]

Re: Flipper (pneumatic) VS Lifter (electric)

one of these

http://www.ebay.co.uk/itm/1-Tonne-10...item3f02488ddb

cut down be ok? I figured that the thread pitch on this must be ok as it doesn't take long to raise on of these by turning it by hand.

how did you connect the jack threaded rod to your drill motor with that set up? did you use a collar or weld it or....?

[maddox10]

Re: Flipper (pneumatic) VS Lifter (electric)

M12 does have a tread of 1.75mm.

[Laser]

Re: Flipper (pneumatic) VS Lifter (electric)

My lifter looks a bit like jamies
here's a pic
[attachment=0:3afxhwcm]untitled 2.png[/attachment:3afxhwcm]

[billy breach]

Re: Flipper (pneumatic) VS Lifter (electric)

Thanks for the photos, has given me a good idea of what to do/ expect.

I think my lifting system will be similar to this now:

[Laser]

Re: Flipper (pneumatic) VS Lifter (electric)

have a look at my thread, this is what I used to build my robot
viewtopic.php?f=111&t=3440

[billy breach]

Re: Flipper (pneumatic) VS Lifter (electric)

Thanks for the link i've just sat and read through it all. You mentioned putting a limit switch on it so when it was fully extended it would cut the motor off.. What did you do in the end? If you were using a speed contoller surley you could have stopped the power to the motor using that?

[Laser]

Re: Flipper (pneumatic) VS Lifter (electric)

I didn't in the end as it was too complicated to do. I just used my eye to see when the lifter met it's end point of lifting

[billy breach]

Re: Flipper (pneumatic) VS Lifter (electric)

I see. Did u just use toggle switch connected to a servo or did you use s speed controller.

[billy breach]

Re: Flipper (pneumatic) VS Lifter (electric)

CONTROLLING THE LIFTER MOTOR
=========================

I ' m thinking of using a servo with a toggle switch or similar to turn the motor on - off - backward, rather than a ESC. Would there be any advantages using a ESC rather than a switch to power on - off - reverse?

Would two micro switches glued to a servo work? if so can anyone help me with the wiring, so that the motor can be on - off - reverse?

Thanks Guys
Billy