Future Proofing

General
3

Hello,
Indeed, a major update is on it’s way for the motor driver electronic. This will be referred as “uDriver V3” or “uOmodri”.

This board promise a lot of new hardware changes and features such as:

  • Powerful MCU with many communication peripherals (EtherCAT, SPI with proper FIFO and DMA, FSI, CAN-FD) and 3 separate CPU cores for control loop, user code and communication.
  • All open source FOC algorithm instead of the current Texas Instrument proprietary libraries. Using now floating point arithmetic for ease of development.
  • More efficient DRV gate drivers and better Mosfets → less thermal losses
  • Higher frequency PD loop from 10k to 40kHz
  • Better velocity estimation
  • Extension port for future shield such as EtherCAT, absolute encoders, etc.
  • 2 x 16bits ADC inputs for optional torque sensor (useful for our big torque controlled actuators)
  • RGB status LED

We also plan to implement new software features such as:

  • Motor temperature estimation from online coil resistance measurement
  • Anti Cogging algorithm
  • Automatic motor R-L identification
  • Better safety shutdown and error reports
  • USB debug port with capability to dump 40kHz values for FOC investigation, sensor noise etc.
  • optional CAN-FD com port to work without masterbaord in some specific scenarios

I might forget a lot of things, but you got it, the expectations are high !

The form factor of the board is the same (50x50mm) but slightly taller, we might need to modify one or two 3d printed part to accommodate for it.

The status of development is quite advance, as we have a batch of working prototype:

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And we are able to control the ODRI motors on test benches:

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We still need to implement a few things to be 100% compatible with the previous version uDriverv2 SPI protocol, we then plan to integrate 6 boards on one of our solo12 by the end of next month.

All this design will be of course open sourced. For now, only the hardware side is public:

We need to do some cleanup on the firmware to be sure we do not publish TI proprietary stuff.

Now, the sad news is that the supply chain of some key parts is not in good shape. The main MCU is out of stock, as the DRVs, and a DC/DC converter. We hope things will get better, we started this design 1.5y ago, when the main CPU was just release, and tried to only choose widely available references, but things have changed.

Apart from this, no update to the electronic is planned.

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