I am building a PMDC powered 4th axis for my machining center. I bought an old stepper motor powered 4th axis and retrofit an odrive brushless motor and optical encoder.
I’m thinking about whether it would make sense to design an Odrive hardware variant that makes integration with machines like this easier. My VMC (like many designed for big fat brushed servo’s) has a 90V DC bus that gets stepped down from mains to power all the drive servo’s. Most of the brushed machines I’ve worked on are similar (70-120v). It uses differential signal encoders for all the axes. In the case of this machine, the motion controller outputs a digital velocity command. Most machines use a +/-10v analog signal for velocity control.
The current Odrive-HV could be used for this but putting in an additional 48v power supply is a bit inelegant especially since the machine already has a beefy DC bus (wiring the differential encoders and control signal up is inconvenient but doable). A variant like this would make retrofitting full scale CNC machines with brushless motors a lot easier since you could reuse the existing power system and connect easily to the original control (or convert to LinuxCNC). Although overkill it could even be used for brushed motors. I wondered if anyone else was considering similar projects.
One question is what max voltage would be most popular. Seems like 120V would cover most older (up to ~mid 2000s) industrial CNC machines that originally came with brushed DC servos. Newer CNCs that use AC servos tend to have even higher DC bus voltages (some over 300V). Supporting that is likely less practical, and maybe unnecessary anyway since the newer machines are high enough performance that converting them is usually a major downgrade.