Perpetual Ball Roller

About: I can't be the only person who spend their whole time making stuff and then never using it?!

This machine is controlled by a PicAxe Microcontroller. A servo (used for steering in R/C cars) is used to tilt the track for a ball to roll round. The degree of the tilt can be controlled by a potentiometer in manual mode or in automatic mode preset instructions on the microcontroller tell the servo how to move.

You can find more about it on this website along with the code for the Picaxe microcontroller.

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    14 Discussions


    4 years ago on Introduction

    I like this as a project and would like to make one, however, it isn't a good example of an instructable without all the information available to enable you to make make it.

    The link with the picaxe code no longer works.

    4 replies

    Reply 4 years ago

    I'm not sure what you mean, I sent a link that works (for pictures and the code) and explained I don't have a schematic (circuit diagram).


    4 years ago

    Sorry, I no longer have it and I didn't bother making a schematic. It's just the standard 8M picaxe download circuit with a servo and pot attached. the code will define which pins to use. if you are not familiar with picaxe just use your favourite microcontroller, it's a very simple project that doesn't require any special libraries.


    6 years ago on Introduction

    This NASCAR style track is interesting, But I would like to see something more on the lines of a Formula One track.


    8 years ago on Introduction

    What about having something like a circle of sandpaper that has ball bearing on top of it, and a track like the one you have here on top of them to keep them in place. Then resting on top and being guided by the track you have some flat object. The sandpaper is rotated by the micro controller which uses friction to spin the ball bearings in place, all in the same direction, which causes the flat object to move round and round the track. I thought it would be cool to see something that's not rounded, and therefore would normally be stationary, drive around in circles.

    1 reply

    Reply 8 years ago on Introduction

    I can half understand what you're suggesting but it's a tricky one to visualise! One day I'll mess around we this concept. People have given me a bunch of ideas for it but unfortunately there has always been something else to do!

    I'd like to see something like this, except using magnetism to pull the ball around the track, I think it would just look cool to see a ball whirling around and no apparent force pushing it.

    1 reply

    I've played with rolling bearings and magnets a bit and the main problem you find is the inverse square law. Nothing. . . nothing . . . nothing . . . nothing . . . WALLOP! Everything happens very suddenly. One possible way is to use a large bearing on a track with the gauge of the track nearly the diameter of the ball to give the effect of a small axle and a large flywheel. That way you can build up rolling momentum but you'd need accurate machining - my experiments tended to bend apart!


    10 years ago on Introduction

    I like this! I just played with a servo for the first time last week (controlled by a PicAxe of course). Great little things and opened up a whole new set of ideas. So many projects . . . So, it's perpetual motion until the batteries run out ;¬)

    1 reply

    Reply 10 years ago on Introduction

    Magnetism would indeed look cool but add a whole load of complexity. I like the fact it is transparent. It's obvious how it works even if you didn't understand what all the parts do. Servo's are brilliant! Probably my favourite "electronic" thing. Dead cheap and very easy to use and like you say open up a whole set of ideas. I too get the so many projects feeling. I was tempted to add the "motion" in the name but I decided it probably wasn't worth the hate mail! "Lisa, in this house we obey the laws of thermodynamics!" @AndyGadget - glad to see your 2nd on Tic-Tac-Tunes. I still haven't managed to get to Maplin to buy the small potentiometer so I can fit it in the box. I must go back and try and code some stuff for it I got distracted with this and other projects.