Using Arduino to control solenoids... mosfets?

Hi,

I am currently designing a project where I want to use my arduino to control a struck musical instrument. I believe the best way to do this is by using solenoids (as used in player pianos) such as those by Black Knight. (6V Tubular push type Solenoid at Farnell, sorry,was going to post a link, but am not allowed as this is my first post).

After some reading around (my electronics knowledge is a touch limited) it appears that by using mosfets to control solenoids velocity control can also be attained. My real question is which mosfet?

Any advice would be greatly appreciated.

Have you seen this:- http://www.thebox.myzen.co.uk/Hardware/Glockenspiel.html

it appears that by using mosfets to control solenoids velocity control can also be attained

No velocity control is northing to do with how you switch it. You can apply a lesser voltage or PWM the control but this will not necessary give you a change in strike velocity, it is a function of the mechanical characteristics of the solenoid. I found there was no velocity effect I could get on my project.

Thanks for the reply. Yes, I checked out your project (which is very helpful, thanks for sharing it) and would have had a go at building it as what I want to make is similar. However, I then read this:

http://www.logosfoundation.org/g_texts/expression-control.html

What do you think? I've been trying to learn enough basic electronics to fully understand it. Unfortunately the mosfets used here are now unavailable.

Interesting link. What in effect he is doing is to make a two bit D/A converter. That is to control the profile of the voltage applied to the solenoid.

6V Tubular push type Solenoid at Farnell

Are they the cheap ones (comparatively cheap)? You have to find a way of returning the solenoid stroke. I used gravity but that limits the lowest strike velocity you can use. Maybe with an other arrangement say springs and mounting the solenoid horizontal you can get better control over the strike velocity.

Unfortunately the mosfets used here are now unavailable.

Not sure why you say this as you mentioned Farnell in your first post:- http://uk.farnell.com/jsp/search/browse.jsp;jsessionid=ARJEH0M1SFFGGCQLCIPZN4Q?N=0&Ntk=gensearch_001&Ntt=IRL640&Ntx=mode+matchallpartial&suggestions=false&ref=globalsearch&_requestid=321076 But any logic level FET will do.

Yeah, I thought it was also very interesting. Worth checking out all the instruments he's built:

http://www.logosfoundation.org/instrum_gwr/automatons.html

The solenoid I had in mind was this one:

http://my.farnell.com/ped/120-420-620-540/solenoid-tubular-push-6v/dp/1518223

Probably going to use them to move a beater with a lever mechanism, I think gravity will also do the job of returning the solenoid here.

As for the mosfets.... I guess I didn't check it thoroughly. Do you think that the voltage from the arduino pins is enough to trigger these?

Do you think that the voltage from the arduino pins is enough to trigger these?

yes the data sheet says 4 to 5V.

No that is not the solenoid I have used.

Impressive set of instruments on that link.

Thanks for your help. I've just ordered a few components to tinker with for now - just a basic setup, and will think about the velocity control later (one step at a time!). If you have any further thoughts, post them here, I'd be very interested.