Another Arduino Drum Machine (a tough one)

hi! the title says almost enough, so here are a brief description and some photos:

i'm trying to build a DIY version of the roland octapad. i want my device to do mainly 3 things:

  • trigger midi notes as it was a midi drum machine
  • play midi notes on a given key on a given octave on a given channel (like a midi keyboard, but with pads instead)
  • do the same as above, but with some sound-synthesis capabilities
    i've almost completed all the hardware needed and the part of the firmware that deals with the display and menu. Now, i'm waiting for a proper enclosure in order to perform some tests on the pads and develop a reading algorithm (i want the pads to be velocity-sensitive).


this is only a developing enclosure: arduino and the display mounted on a plastic piece of tubing, i suppose. You can also see the splash-screen :stuck_out_tongue:


these are the multiplexer board and the buttons board, that only uses an analog input.


here's another pic showing menu navigation. my program allow a very complex menu organization, with possibly infinite levels of submenus.


in this one you can see a setting submenu: it allows you to change among different values (the key, in this case). Each setting submenu recall the same function, but with different parameters.


this is the last one: these are the piezo conditioning circuits, used to properly manage their signal. the two boards are identical, and each one controls 4 pads.

suggestions are welcomed :wink:

since no one replied, i'm wondering if this is the right forum area to post a project :roll_eyes:

suggestions are welcomed ... since no one replied

What is there to suggest? It looks like a well done project.

60 people viewed this topic since yesterday. Apparently, the horde agrees with me.

Hi,

The Internet is a strange place, there is one RC forum I used to visit a lot, if you posted something very cool that you had completed you would get a lot of views and no replies or comments. However if you played dumb and asked what colour should I paint x you would get two hundred replies overnight.

Strange place. Nice project.

If your after suggestions here are two - add beat reactive lights and something cool and unusual as an enclosure.

Duane.

rcarduino.blogspot.com

You might try reading some of the posts WilliamK has made also re: drum macines.

DuaneB:
Hi,

The Internet is a strange place, there is one RC forum I used to visit a lot, if you posted something very cool that you had completed you would get a lot of views and no replies or comments. However if you played dumb and asked what colour should I paint x you would get two hundred replies overnight.

Strange place. Nice project.

If your after suggestions here are two - add beat reactive lights and something cool and unusual as an enclosure.

Duane.

rcarduino.blogspot.com

you asked for a cool enclosure? what do you think about that?

with the smaller half being foldable. same size of an A4 shit of paper, just a bit thicker :wink:
of course this was only a quick rendering, just to get the idea. the real one is waiting to be painted a mounted, while, on the hardware side, i'm still having some troubles with cables.
i'm wondering what material should i use to make the pads themselves.. i want them to be softy but responsive at the same time, offering a nice "bouncy" feel.. any suggestion?

As a drummer, I always preferred something like 1/4" rubber on wood if an actual stretched drum head was not available.
Something like this is good.
http://www.rolandus.com/products/productdetails.php?ProductId=192

CrossRoads:
As a drummer, I always preferred something like 1/4" rubber on wood if an actual stretched drum head was not available.
Something like this is good.
http://www.rolandus.com/products/productdetails.php?ProductId=192

yeah, that one is quite the same kind of material i would like my pads to be made of. do you know where i can find it?

Google?

CrossRoads:
Google?

i know, the problem is that i don't even know what i should look for :S "rubber" sounds a bit too generic, doesn't it?

First, I want to say nice work and it is easy to tell you are really putting in some effort! Also, good job on making your own circuit board! As far as rubber, perhaps inner tube rubber would work. I am thinking of the tube that is found in heavy trucks, lawn mower tires, etc..

No, you need thicker rubber.
Like 1/4" thick neoprene maybe?
http://www.rubbersheetroll.com/neoprene-rubber-strips-commercial-grade.htm

firstly, thanks for the suggestions!! i'll try my best to get some of that stuff!
secondly, here some updates: i received the box that will contain all the boards and stuff, i had some trouble with the screen, and i have to find a way to glue the piezos. i'm a bit late with the time table. >.<

i have to find a way to glue the piezos.

Hot glue seems to work for a lot of things. :slight_smile:

cyclegadget:

i have to find a way to glue the piezos.

Hot glue seems to work for a lot of things. :slight_smile:

yes indeed, but i'm afraid i would get that if i hit one pad, each of them will play

quick update:

  • due to current feeding issues, i (temporary) dismissed the piezo pads and their boards in favor of a bunch of tactile switches
  • the software is c o m p l e t e!!

it took so long for me to reply because i was trying to build some kind of filter for the audio output. screen-shots coming soon :smiley:

Hi!

Do have a video? To see how it works?