Benchtop Tests and Interference

Post date: Apr 20, 2015 3:0:45 PM

I tested my software with two axes this weekend. Initially nothing worked because of electrical interference, which I kind of expected. I made improvements to power distribution, cable shielding, and decreasing ground path impedance. I can still occasionally get a blip somewhere after running for 10-30 minutes. The feedback blip will cause a following error fault and the simulated machine will stop running. Next steps are to make the connections as short and well shielded as possible. SPI connections are supposed to be over very short distances, so with 4.5 feet of parallel port cable + 1.5 feet between driver boards and the computer, it wasn't really a surprise. I probably need to move everything into its final so I don't have to build everything twice. In the end, I expect 18-24" of total cable length to be used. Hopefully that will fix it without having to do anything exotic.