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ICBM project reached revision zero.


I’m pleased to announce that Interactive Controller for Brushless Motors reached the “revision” phase. I finished implementing and verifying the core functionality and now have a handy tool to test and compare brushless DC motors. In addition to basic abilities to spin a BLDC and change A4960 parameters, demonstrated in this video, the controller now has the following:

    Untethered operation. Basic functions like start, stop, brake, and motor speed change can now be performed via controls on the board – no terminal connection necessary.
    Separate power bridge. Power MOSFETs have been moved to a second board; this allows me to use the controller to drive loads with different power requirements. Also, replacing burnt MOSFETs is easier this way.
    A heartbeat LED indicator is added – when a code crashes I can see it right away :-).

The circuit is built on a single-sided homemade PCB. The copper on the other side is kept intact and it serves as a ground plane and a heatsink. The Eagle CAD files as well as QM model file and PIC24 code generated from it is hosted on github. PDF files for two boards are also in the tree, the files can be printed on a laser printer and used in toner transfer process.

The following pictures show details of the project. Please take a look – and stay tuned for the updates.



Interactive Controller for Brushless Motors PCB – first draft

I finished laying out the first revision of the PCB for ICBM. In addition to what is shown in the video I decided to add rotary encoder as a second control to change PWM duty cycle. RUN/STOP and BREAK functions will have their dedicated hardware buttons as well. The MOSFETs are mounted on a separate daughter board, this way I can have drivers for different power requirements. The first one I routed accepts DPAK-packaged transistors. The Eagle files plus pdf schematics for both boards are on github. Enjoy!

Oleg.