So, I've been working on the Toy Motor Controller. Over the past weeks, I have designed the mechanical case, revised the PCB and worked on the firmware. This device is still a work-in-progress.

Mechanical Case

The mechanical case consists of front cover, back cover, a couple of knob caps, a button and a power slider switch. The battery tray is affixed to the back of the top cover using a couple of screws via a couple of screw holes that comes with the tray.

It's the first mechanical case that I've ever designed in my life. I'm glad that it's working. And I'm happy that I can finally put the 3D printer that I've got into good use. :D

Here is some photo showing the mechanical case of the second revision of PCB:

Second Revision of PCB

I have revised the PCB design. Compared with previous revision, now that it has the following feature:

• More compact
• Wider input voltage range. Previous revision: 1.85-5.5V. Current revision: 1.4-5.5V
• Dual motor output port. Previously it only had one output port.

After spending hours of time, I have assembled a unit of this revision of PCB. I found that it does have minor issues, including a couple of capacitor footprints are having the size that's slightly off, and some silk mark issues. But they aren't anything critical so I can get away without fixing them for now. :P

Here's a photo showing the difference between the previous revision and the current revision:

Firmware Development Updates

As for the firmware development, the driver code is mostly completed. Now that it's time for me to implement the actual feature on top of the driver code that I've written.

I've also tested the hardware using the driver code. At this stage, there's no evidence of existence of major defect in electronic design.

Production

With the current development status, both the mechanical and electronic design seems to be working fine. I believe that I can go ahead and assemble 4-5 units of this device.

Due to the minimal ordering quantity of the PCB, I've got a few extra PCBs. I'm gonna find a time to purchase the components and solder them onto the extra PCBs.

This time over, I'm gonna purchase solder paste stencils as well. It took me hours to fix issues associated with putting incorrect amount of paste in my previously assembled units. I'd rather to spend an extra few dollars on getting stencils so that I can apply the exact amount of paste needed to avoid running into this problem again.

I don't think that this device would have any good amount of demand. I'll be using this 4-5 units to evaluate the demand and see if I should outsource the assembly or if I should continue to do the assembly on my own. I've done the math. Apparently it's well worth the cost outsourcing the assembly if the demand is >20 units per batch.

That's it!

That's it for the update on this project. I'll update you guys whenever there's any news. See you soon! :)