EtherCAT
The hades revision has integrated EtherCAT communication for real time capabilities with higher bandwidth. The communication also allows for the devices to be connected in series to allow one master device to control multiple actuators. The RJ45 connection also introduces isolation between each motor driver ensuring communication.
Hades (second revision)
All in one solution
With the proven functionality of our first revision, Zeus, we combined the motor control hardware, microcontroller, and EtherCAT all together. The board also includes resettable input protection, voltage regulation, CAN, and interfaces to our custom encoder board.
Motor Control Hardware
Hades is designed to run off 24V to 48V with a continuous output of 10 amps. To save on cost we moved from individual half bridge drivers and current sensors to the DRV8323 which also added additional features such as variable current gain and slew rate control of the gate drivers.
Microcontroller
The microcontroller used is the TMS320F28379D which is specifically designed for motor control applications. It features a 200MHz dual core with 16 bit 1MSPS and high resolution PWM. This gives a sizable of headroom allowing us to run the motor control loop at 40kHz while also using a real time operating system to handle communications, safety systems, and various housekeeping.
Current Status
After the mess of delays caused by COVID-19 we have finally been able to start assembling and testing Hades. As of the beginning of June we have started testing the voltage rails.