looking for some info about magnets for kinetic sculptural project

[slatepipe]

hi there

i am a practising sound artist and have in mind a large sculptural piece for my next project.

the piece will be based on a magnetic pendulum type of executive toy, similar to the image link below, and i anticipate it will be about 2.5m-3m tall

the magnets will have sensors in them which will send on/off signals wirelessly to a computer when the pendulum interacts with them. this will then trigger sounds and form a kind of random composition.

i have been doing a little research on the internet and found this forum and thought it seemed like a reasonable place to put some ideas forward and ask some questions :

i want the ball on the pendulum to have a magnet in it so that it can be attracted and repelled by the magnets on the base. i want the magnets on the base to be able to switch polarity so that the course of the pendulum's swing can be altered while in use. i think perhaps this could be done via a remote control of some sort. the magnets on the base need to be movable so different patterns of swing by the pendulum can be performed. they also need to be able to be attracted or fixed to the base so that they do not 'jump' onto the pendulum's magnet.

can anyone give any advice on types of magnets that they would consider to be suitable? i am thinking that they will have to be electro magnets, possibly battery powered,so that they are freely moveable, but i realise other forms of power could be viable. price is a factor to consider, i can afford a reasonable amount but i dont want this to cost the earth.

many thanks in advance for any help and advice.

 

[EdStainless]

Use a strong permanent magnet in the pendulum. There are ways to build this as an assembly to get higher working field strength.
Use electromagnets on the field plate. Maybe have various sockets to plug them into to power them.
You could actually use the coils as sensors to know when the pendulum is near and when to turn on.


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Plymouth Tube

 

[slatepipe]

hi there
many thanks for your reply
please excuse my apparent lack of knowledge on the subject but could you please give a little more info on what you mean by 'ways to build to get higher working field strength'.
also could anyone possibly point me in the direction of some types of electromagnet that they think may be suitable for the task?

many thanks for your help

http://www.slatepipe.co.uk

 

[EdStainless]

You need as high of field strength as possible.
Rather than just using more magnet you can put pole pieces on the magnet to focus the field.
You can do the same with the electromagnets winding wire around steel cores to help focus the field.


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Plymouth Tube

 

[slatepipe]

hi there

sorry for the delay in replying

can you provide some guidance from somewhere on building what you would consider to be an appropriate electro magnet for this intended project? can you point me in the direction of anything online that you would consider to be useful?

"put pole pieces on the magnet to focus the field" - forgive my ignorance but this is all a new area of interest for me, can you explain a little further what this means ?

many thanks for your help and information

http://www.slatepipe.co.uk