I am currently attempting to take advantage of one of the first consumer-available FOC controllers (Zubax Myxa) on vehicles powered by Arduplane. Although there are numerous interface options available, I have chosen CAN for its advantages in monitoring battery and ESC status. There are a few issues that have come up as barriers.
#1. Ardupilot does not currently log or transmit UAVCAN ESC information to the autopilot. I am interested in viewing current draw and RPM information from a GCS in order to monitor the propulsion system health. Logging is also important, however I understand this is an ardupilot feature problem, not a zubax problem.
#2. There is no automated brake feature available at idle. This is critical for safety and landing reliability. When props spin at 0 throttle (freewheeling), they can often dig into the ground and damage themselves on belly landing planes. This is a problem for both folding props and fixed props. Although phase manipulation works to really lock in the props, other traditional inexpensive ESC’s do a good job of allowing a little slow movement while resisting speed. They act more like an extreme damper more than an active brake, and it really helps knock props into a safe position even if they contact the ground on landing. In the current setup, it’s actually better to keep the props spinning at minimum speed rather than let them freewheel to a much higher velocity.
#3. Kucher is only available to Linux. The quick-start guides are good for anyone who knows linux intimately, but not for a standard/advanced windows user. These devices can only be set up by the linux program, and unfortunately that is significantly restricting the market. I am quite computer literate, but I still had to have a programmer friend of mine help. I was also informed that updating any of the programs on ubuntu would result in Kucher not working, so now I have to be mindful of what I do. The windows program really needs to be developed - it’s been proposed for over a year from what I read, and it’s still not done. In addition, the Kucher program does not allow saving or uploading parameters to multiple devices - you must individually enter each and every parameter for multiple devices. On something like an octopter or for multiple builds, this would get annoying fast. Most set-up programs (like blheli suite) have a save/load parameters feature that is very helpful.
#4. Parameters have little/no documentation. Although they have good names, there is no description on most of them unless you happen to stumble on them in the quickstart guide… on the forum. A forum is no place for reliable documentation in my opinion, and I can’t seem to find a resource for the other parameters or what they do.