Calling all Electronics Wizards and Open Source Hardware enthusiasts to help me fix my Motor Controller…

Okay. So, i’m a little embarrassed that this thing is still not working. I’ve made cool progress on it over the years, but not the part that matters… that it actually works. This should not be that hard. Since it’s basically an HIP4081A beefy full h-bridge controller and an Arduino it should not be all that complicated. I think what i need to do is just spend some money on known good components and true schottky diodes and mosfets and just breadboard this thing out. Once i can get this reliably working on a breadboard i can come back to the PCB design stuff. I know last time i messed with it i had a few PCB wiring issues and when i was testing the h-bridge i could only get one side to turn on. The other side was shorting out somehow.


Having said that, i’m still pretty happy with the overall PCB design and direction that is heading. I really enjoy the two PCBs that plug into each other via male and female headers ans sockets. I just put up my files (in their old unkempt state) onto GitHub for version tracking and in true Open Source Hardware fashion for others to hopefully help collaborate with me on this. I really really really want to see this thing work someday and turn into a cool motor controller that people use all over to build cool robots and stuff with in the near future.


So, please… If you are good with electronics and electronic theory, especially motor control, if you are an open source enthusiast, if your good with git, if you are good with EagleCAD, if you have an interest in a cool Open Source motor controller based on MOSFETS, if you were a user of the old FIRST Robotics, VEX Robotics, or IFI Victor 884s or 885s that this design is based on (now a defunct product to my knowledge), if you’d like a motor controller you can hack, use I2C or add a CAN bus or some other device such as a current sensing circuit, or who knows what else, then PLEASE PLEASE Help Me! Help me get this thing working and ready for market and usability and hackability. I’m not ashamed to ask for help or to admit that i need it. I’m proud of how far i got with as little electronics knowledge as i do have, but concede that there are so many other people out there that can help!




I have uploaded the last freeze of this project onto a new github project for you all to easily get the source files here:

I’ve also designed a neat little 3d printable base to keep this thing from shorting out. And i will track down the other design files that are relevant or that this design is based on in the next couple days / weeks.



*Bonus Offer: I have several old PCBs of V. 1.0 laying around. For anyone willing to help me with this project i would be willing to send you up to 3 copies of the top and the bottom boards each to play with (while supplies last). There are i think at least two potential PCB trace errors (that i can’t remember what at the moment) that are on the boards, but hey, free boards and it’s not that hard to cut a trace or two and rewire if needed. You would just need to obtain the needed mosfets, diodes, arduino, and HIP4081A h-bridge driver chip to work on the project. Heck, i’m even willing to entertain replaccing the HIP4081A chip to a different one if there are any better or cheaper options that do basically the same thing. Please Help 🙂


Continuing Progress on the XYZZY Motor Controller


I think i’ve finished the design for the XYZZY Motor Controller, which for me is a big statement. I embarrassingly probably even said it before too. But anyway both the top board and the bottom board are done in Eagle Cad and i think i’m satisfied. The top board relatively stayed the same since it’s design was fairly sound. All that was needed was a few safety diodes for the mosfets, some led’s, and some minor resistors which were not critical. The bottom board was another story however.

It required a complete redesign except for the basic underlying parts. Many of the items i had on the board were just potential “goodies” that were extraneous and non-critical, so i removed them. Not only did it help remove extra unrouted wires, it helped clear up some much needed room. In the end i ended up with some extra room that i turned into a tiny proto board area that i’m quite pleased with. Along the way i fixed a few errors on the schematic and routed things nicer than they were before. I think all that it needs now is to order up some PCB’s and do some more testing and programming.

The only things i would like to change are the screw terminals. The ones that are on the schematic now are much too small for a large amp motor. The problem is i can’t seem to find an Eagle Cad footprint for one. I may have to end up creating my own part in eagle cad eventually. If you know of one please let me know in the comments below! I’m looking for something like these: photo1, photo2, photo3.

The XYZZY Motor Controller is a modular open source hardware mosfet speed controller h-bridge. It has been designed to be able to handle high current motors with the parallel mosfet design. It has been designed to be hackable and DIY accessible (hence the all through hole design). It has been designed for flexibility. Since it has been created with the hope in mind of a built-in arduino brain it can be easily programmed for many things. I’ve routed one PWM capable I/O port to function as a PWM directional input (modeled after the IFI Victor 884 servo input design). But one feature i’m happy to include is an easily accessible I2C port. This port gives the motor controller many potential abilities. One idea is to use the I2C port to expand it’s capabilities (such as a current sensor), or i think it would be cool to use I2C to daisy-chain several motor controllers together to help save wiring and to provide real-time feedback to a master microprocessor or computer. Another cool “feature” is that possible boards could be fixed with half the parts. If for example the mosfets died for some reason, but the bottom components were fine (or vice versa) you could use the good parts with other good parts. Since my old top board is basically the same i plan to test it with a new bottom board sometime in the near future. I expect it to work fine.

The schematics are somewhat rough. I’ve tried to clean them up as best i can. But don’t expect them to be pretty. The reason one schematic has floating wires going nowhere on one side is that at one point these were part of one schematic. To create the two board system with the pluggable pin headers i had to split them into “two projects” at one point in time.

bottom_sch_v1.0 top_sch_v1.0

If you would like a copy of the current Eagle Cad files please let me know. This is an Open Source Hardware Design. I would love to see these in the wild or even improved versions of it. Perhaps someone with surface mount experience can create one with smaller parts. More prototype testing to come soon, i hope! 🙂

Update (9-15-15): I’ve updated it again only slightly. I’ve changed the resistors to have bigger pads using the adafruit eagle cad library parts, and instead of screw terminals i’ve decided to use spade connectors or quick disconnects. These make it less cumbersome to disconnect motors and power and no loosing of screws, but also saves space (which was more critical). I couldn’t find a library that had a spade connector already, i had to make it myself. It actually wasn’t too hard.

top_board_v1.0 bottom_board_v1.0

Updating and perfecting the XYZZY Motor Controller


I’m working on finishing and perfecting an old project of mine (by a few years). The XYZZY Motor Controller (H-bridge). The old design was only somewhat functional. Enough to prove proof of concept (barely), but i want a sleek, finished version that people can actually use. So i’m working on perfecting this prototype design. I’ve just updated several things on the top board, and i think it’s done. The biggest issue was a pretty major design flaw which was that i forgot to add the safety diodes for motor kickback. In simple terms that meant that when the motor stopped turning or i switched it from forward to backward the electrical energy would destroy the Mosfets! …oh.. noo… Yup.

Not to worry, they are there now. I will be wiring them in manually to some of my old prototype boards to test soon. This design is progressed enough to update it to V1.0 instead of Rx.x number. Although the top board is finished, the bottom board needs quite a bit of work and possibly major redesigning. from the looks of my old design for the bottom board it looks like one feature i wanted to implement was an I2C bus. That would make it cool to connect them together and then to a microprocessor to monitor them in real-time. The only sensors to monitor at this point was the inclusion of a crude temp sensor and monitoring the RPM of the fan. Although i was hoping to build an arduino chip built in. When i eventually purchase new PCB’s i think this revision is finally deserving for the color red! Although purple or black would look pretty sick too. Any comments are welcome.

This is an Open Source Hardware Design.

DSCF7247 DSCF7248



HP/Agilent 03458-66509 7V DC Reference Clone

This past week I’ve been helping my dad design some replacement boards for the HP/Agilent 3458A multimeter.  I don’t know much about what these actually do, but he says that this board is the heart of the 3458A. Apparently it is some sort of DC reference board which uses the LTZ1000.  Anyway the protoypes seem to have tuned out great. He thinks he might try to sell his boards on ebay. The cool thing is that we tried hard to keep everything pin compatible so they should work fine in an actual 3458A or standalone in a project like this one.