I finished a very simple and quick project recently. It is a programmable cat feeder device. The device is just made for one single portion, but it uses this slide which produces the distinctive sound if the pellets hit the bowl. It is no replacement for the usual feeding of the cat, but some flexible addition to give food out of the regular times.
The whole build was done in roughly four days, using a very quick prototyping and build method.
Design and Build Process
First I had to make a decision about the final size of the device. I used Autodesk Fusion360 to create a model of the device and try to fit all required parts into the device.
This is one of the last designs I made until I had the right size. I used a different mechanism as shown here, the important part was to get the right size.
Next I bought plywood in the right sizes for the outer shell of the case. I also got some additional panels fitting inside of the shell for the internal structure.
I created the shell with four sides, left the top and front side open. To work quickly I fastened the panels with hot glue in place. This has the benefit that you can remove panels using a hot air gun in the prototyping stage.
I just finished part 2 of the project description for the Outmoded Sequencer. In this second part I describe the steps from the prototype to the final device. I copied the preface from the page after this link .
Building the Outmoded Sequencer was a really interesting project where I learned a lot. It was the first project with a custom designed PCB. Usually I just solder everything onto stripe boards, because I only produce one single device. The complexity of this device with the matrix forced me to design a proper PCB, soldering everything on a stripe board is feasible but requires more space and a different approach for the matrix.
Not everything turned out as well as expected. First there was the idea with the matrix using steel balls as switches: Even with the magnets generating a certain force to the pads, the steel balls do not connect as reliable as I would like they do. As you can see in the demonstration video, it is still possible to have a lot of fun playing with the sequencer – however better connections would make the experience even better.
Should you build your work Outmoded Sequencer? Yes, absolutely! But you should definitely use a different approach for the matrix. Best first only experiment with the matrix part until you have a working solution there before you add the other parts around.
Should you use the provided PCBs? No, better design your own board especially implement the matrix in a different way.
Should you use the circuit design as provided? Yes, definitely! The design is, in my opinion, a very good start and should give you a reliable and working device with minimal effort. Keep in mind: This is a minimal design and there and many ways how to improve certain aspects of the circuit. So feel free to address the problems if you have components left, to spend on this project.
Hurray! I just finished the final Outmoded Sequencer device. The tuning of all frequencies was way faster than I expected, because I used a new method. Have a look at the following photo gallery before I tell you some details.
You can see the device is build like a control desk, with the PCB a little bit at an angle. The left knob on the top controls the speed of the sequencer and the right one the volume.
A did a few tests already and the idea with the steel balls is working, but not great – just ok. So sometimes they do not connect and you have to move them a little bit until they make contact again. Most of the positions are working always without problems.
It is a great fun to play with the device, changing the pattern while the melody is playing. Now everything is finished, I also can move two steel balls at a time which can create interesting variations.
Next I will do a detailed video, where I demonstrate the final Outmoded Sequencer. It should give you a better impression of the device in action. I will also setup a complete filter chain, so you can experience how easy you can use the sound of the sequencer as input to do various interesting effects.
I will also add the second part of the project page, where I explain some of the details about the magnet matrix and how the whole thing is built.
There are seven absolutely perfect PCBs left, so I think about to give them away if someone is interested into building the project. But be aware, this is no kit, just the plain PCB. You also have to use the exact same components as I did – or at least ones which perfectly fit into the holes. All components should be available to buy at various stores, and I will provide the exact part numbers.