Highly Liquid Forum facebook twitter google plus rss feed
  #1  
Old 01-15-2015, 03:12 AM
twf twf is offline
Junior Member
 
Join Date: Jan 2015
Posts: 2
Default Triggering solenoids

Hi there,

I'm a musician who knows nothing about electronics. I want to use the MIDIWidget to trigger an array of 5v solenoids, each corresponding to a MIDI note. How would I wire that, and do I need any extra components?

(I should probably learn something about electronics before embarking on this project but I'm keen to just get something working quickly).

Thanks for your help.

Tim F
Reply With Quote
  #2  
Old 01-15-2015, 02:41 PM
John's Avatar
John John is offline
Moderator
 
Join Date: Jan 2009
Posts: 3,007
Default

Quote:
Originally Posted by twf View Post
Hi there,

I'm a musician who knows nothing about electronics. I want to use the MIDIWidget to trigger an array of 5v solenoids, each corresponding to a MIDI note. How would I wire that, and do I need any extra components?

(I should probably learn something about electronics before embarking on this project but I'm keen to just get something working quickly).

Thanks for your help.

Tim F
Hi Tim, welcome to the forum. You will do yourself a great favor by learning the basic electronics concepts of voltage and current. Here are some links that will help:

http://forum.highlyliquid.com/showthread.php?t=14

The solenoids most likely can't be driven directly by the MIDIWidget because they draw too much current. The MIDIWidget can only supply 24mA per output.

However, you can use an NPN driver circuit to solve this problem.

The basic idea can be seen here (the MIDIWidget is just like the MD24 for your application):

http://forum.highlyliquid.com/showthread.php?t=3

Note that the first diagram assumes a solenoid with a 9V operating voltage. You would naturally use a 5V supply for your 5V solenoids.

I hope that gets you a start. Beyond that, Google will get you lots of info. Here's the same concept, but written for Arduino. An Arduino digital output is very similar to a MIDIWidget output.

http://playground.arduino.cc/uploads...oid_driver.pdf

You can also try using an ULN2803A IC, which is an array of 8 drivers. So you could wire up to 8 MIDIWidget outputs and 8 solenoids to a single inexpensive ULN2803A.

http://www.ti.com/lit/ds/symlink/uln2803a.pdf

All of this has the caveat that you need to know the current draw of your solenoids and make sure that the drive circuit can handle it.
Reply With Quote
  #3  
Old 01-15-2015, 11:15 PM
twf twf is offline
Junior Member
 
Join Date: Jan 2015
Posts: 2
Default Thanks

Thanks very much John,

I'll do as you suggest and learn some basics before attempting this.

Cheers
Tim
Reply With Quote
  #4  
Old 01-29-2015, 02:24 PM
Torre1 Torre1 is offline
Junior Member
 
Join Date: Jan 2015
Posts: 4
Default

Sorry to piggyback on this thread but I plan to do the same this as the OP to drive 21 relays. I assume this is simple hookup?

Quote:
Originally Posted by John View Post
....The solenoids most likely can't be driven directly by the MIDIWidget because they draw too much current. The MIDIWidget can only supply 24mA per output.....
Couldn't this be solved by using optocoupler relays which require very little current and an alternate 5v power source?

I plan to use this to play organ chimes similar to what a former forum member did a couple of years ago.

Thanks,
Mark
Reply With Quote
  #5  
Old 01-29-2015, 09:16 PM
John's Avatar
John John is offline
Moderator
 
Join Date: Jan 2009
Posts: 3,007
Default

Quote:
Originally Posted by Torre1 View Post
Sorry to piggyback on this thread but I plan to do the same this as the OP to drive 21 relays. I assume this is simple hookup?



Couldn't this be solved by using optocoupler relays which require very little current and an alternate 5v power source?

I plan to use this to play organ chimes similar to what a former forum member did a couple of years ago.

Thanks,
Mark
Hi Mark,

Welcome to the forum. I'm going to publish a circuit that uses the ULN2803A chip to drive relays. It is a simpler and cheaper approach than using photorelays to control the coils of the larger relays. More soon. Please bump if a few days go by with no follow-up.
Reply With Quote
  #6  
Old 01-29-2015, 10:44 PM
John's Avatar
John John is offline
Moderator
 
Join Date: Jan 2009
Posts: 3,007
Default

Let's say you have relays or solenoids that require 9VDC to activate. You can use a ULN2803A IC to drive them as shown in the attached diagram.

The ULN2803A can sink up to 500mA per output, or up to 2.5A in aggregate for a brief time. It is best to keep the current flow much lower than the maximums to avoid overheating.

This would work equally well if the relays or solenoids require 5VDC or 12VDC. Just change the power supply in the diagram accordingly.

For more details on the ULN2803A, check out the TI product page:

http://www.ti.com/product/uln2803a

It's widely available, and costs less than $1 per IC.
Attached Images
 

Last edited by John; 02-22-2015 at 06:40 PM. Reason: Edited to provide more realistic current recommendation.
Reply With Quote
  #7  
Old 01-30-2015, 02:48 PM
Torre1 Torre1 is offline
Junior Member
 
Join Date: Jan 2015
Posts: 4
Default

Thanks John.
Since I will be controlling 21 relays, I would need three of these, correct?
Also, I assume outputs 8-23 on the MIDIWidget would be connected the same way to output the 21 notes?

You may recall forum member Jeff had done this with the MD24 several years ago. He was gracious enough to help me start my project last year and sadly passed away in the Summer.

Thanks again,
Mark
Reply With Quote
  #8  
Old 01-30-2015, 04:49 PM
John's Avatar
John John is offline
Moderator
 
Join Date: Jan 2009
Posts: 3,007
Default

Quote:
Originally Posted by Torre1 View Post
Thanks John.
Since I will be controlling 21 relays, I would need three of these, correct?
Also, I assume outputs 8-23 on the MIDIWidget would be connected the same way to output the 21 notes?

You may recall forum member Jeff had done this with the MD24 several years ago. He was gracious enough to help me start my project last year and sadly passed away in the Summer.

Thanks again,
Mark
Mark, yes, just add two more ULN2803As and repeat the pattern for outputs 8-15 and 16-23.

This is the first I have heard about Jeff passing away. I'm very sorry to hear it. It was a pleasure to correspond with and do business with Jeff over the last few years. I'm glad to have his contributions here on the forum.

Last edited by John; 01-30-2015 at 04:53 PM.
Reply With Quote
  #9  
Old 01-31-2015, 02:04 PM
Torre1 Torre1 is offline
Junior Member
 
Join Date: Jan 2015
Posts: 4
Default

Thanks John.

I didn't know Jeff personally but like I said, he was very gracious to me when I asked him questions about his work.

If you are interested http://www.findagrave.com/cgi-bin/fg...GRid=132747201
Reply With Quote
  #10  
Old 03-13-2015, 09:18 PM
John's Avatar
John John is offline
Moderator
 
Join Date: Jan 2009
Posts: 3,007
Default

Here are a couple of my experiments controlling solenoids with the MIDIWidget.

https://www.kickstarter.com/projects.../posts/1163262

https://www.youtube.com/watch?v=P2_bHn62eY8

https://www.youtube.com/watch?v=E_2Yo0d4fTk
Reply With Quote
  #11  
Old 05-13-2015, 02:23 PM
NoahR NoahR is offline
Junior Member
 
Join Date: May 2015
Posts: 2
Default Triggering solenoids with multiply midi channels

Hi guys,
I'm thinking about using the MIDIWidget for a player guitar that I'm building. I need to activate 2 solenoids per note one to push down a string and another to strum the string, the solenoids that strum the strings need to be triggered by multiple midi channels, I'm wondering if it's possible to set this in the setup of the board to automatically happen or if it needs to be done with multiple MIDIwidget board.

Suggestions are appreciated.

Thanks,
Noah
Reply With Quote
  #12  
Old 05-13-2015, 03:18 PM
John's Avatar
John John is offline
Moderator
 
Join Date: Jan 2009
Posts: 3,007
Default

Quote:
Originally Posted by NoahR View Post
Hi guys,
I'm thinking about using the MIDIWidget for a player guitar that I'm building. I need to activate 2 solenoids per note one to push down a string and another to strum the string, the solenoids that strum the strings need to be triggered by multiple midi channels, I'm wondering if it's possible to set this in the setup of the board to automatically happen or if it needs to be done with multiple MIDIwidget board.

Suggestions are appreciated.
Hi Noah, welcome to the forum.

Each MIDIWidget output can be configured to respond to events on an independent MIDI channel, so no problem there.

However, if you want to automate complex gestures, probably with a delay between the different aspects of the gesture (push down on string, wait xx ms, then strum string) and trigger them with a single MIDI note, then the MIDIWidget might not be a good choice.

As I see it, you have two options:

1) Control each of the different mechanisms with independent MIDI messages, and then use MIDI sequencing to generate the complex gestures you need. This can be done with a single MIDIWidget board. Or,

2) Use a full-blown electronics prototyping platform like Arduino or Teensy to allow for custom, complex actions based on individual MIDI events.

Does that make sense? I hope this helps. At the very least, scenario 1 should be the quickest way to start prototyping.
Reply With Quote
  #13  
Old 05-15-2015, 04:20 AM
NoahR NoahR is offline
Junior Member
 
Join Date: May 2015
Posts: 2
Default Triggering solenoids with multiply midi channels

Thanks John!

That was my thought process as well.
Reply With Quote
  #14  
Old 05-20-2015, 02:15 PM
Cisplatin271 Cisplatin271 is offline
Junior Member
 
Join Date: Apr 2015
Posts: 3
Default Pinball solenoids.

I'm pretty excited to expand my drum kit with this 24 line design. I used an older highly liquid board that has 8 outputs. My kit uses solenoids I ordered from pinball supply websites.
I had some challenges that anyone thinking of this option should be aware of.
1: these solenoids were the best ones for a decent price that I found. They were strong enough to move drumsticks, and mallets like those used on a field bass drum. Very fast, very low latency.

2: there are different strength solenoids. The medium strength ones were sufficient for everything but mallets, for those, use the long field pinball solenoids.

3: they run on 70v with high current. This is enough to do light welding. I bought a 70V 20A p/s for a CNC router. 20A is dangerous! I'm an EE, so I don't recommend this to anyone who does not have experience dealing with high voltage.

4: relays will weld shut at this value. I built mosfet based high speed switches after trying 2 different relays rated for this power from Digikey. They get hot so the mosfets most be thermal coupled to a heat sink.

5: familiarize yourself with inrush current, and the inverse of this which is when the field colapses. The magnetic field converts back to a voltage in the opposite polarity, and it needs somewhere to go. If you don't use diodes and resistors to absorb this, it will damage something eventually. Pinball solenoids include 2 coils, one for the drive, and the second for holding the flipper energized. I have not tried removing the holding one yet, but it may help with heat. I get a lot of arcs here. Opening this helped.

In the end my kit runs really loud. I can do rolls on a snare that are intimidating using 2 solenoids and sticks. Good luck with your kit. I can't wait for delivery...
Reply With Quote
  #15  
Old 08-15-2015, 03:15 PM
Praxisaxis Praxisaxis is offline
Junior Member
 
Join Date: May 2013
Posts: 3
Default

I'm starting a similar project.

Just a thought. . . using contact mics for percussion may mean less energy required to generate an acoustic sound, so the solenoids won't have to be extremely powerful. Piezos are easy to build up into contact mics and very cheap.
Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 05:25 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.