KDE KDECAN ESC Review

I’m putting this in rants and raves because it has some of both. I’ll split this up into different categories to focus the discussion a little. This will be coming from a user of the KDE-UAS85UVC ESC purchased from KDEDirect roughly 10 months ago. Keep in mind some things might have changed with respect to the physical product and the shipping since then. Our use case is with fixed wing aircraft and non-KDE motors.

The box and contents

The overall design of the box is nice. The cardboard and foam were well selected and both have a good fit. The box that the ESCs shipped in was adequately packed and everything arrived without issue.

There were no CAN terminators included. Terminators are included with the full cable set (sold separately), but for a fixed wing aircraft that means that only half of the purchased cable set will be used. We ended up purchasing terminators from another vendor after emailing KDE asking to purchase the terminators separately. I would like to see this particular product line expand buy 1 or 2 more SKUs having kits with short and long CAN JST-GH 4 pin cables with a JST-GH 4 pin terminator to target fixed wing/single ESC use cases.

There are are 3 smaller female bullet connectors and 1 larger pair provided. This is only a small downside, but adds one more thing to be purchased from another vendor. This should be changed to either ship matching pairs or ship nothing. The reputable vendors for bullet connectors sell in pairs which just creates more waste.

The ESC hardware

Our use case is fixed wing aircraft ranging in weight from 10 lb to 20 lb. Each setup has a different propeller and motor and creates different demands for the ESC operation. Everything worked as expected once the settings were correct.

The enclosure is nice and is very robust. It is well machined (maybe those deeper grooves chew up ball mills though) It has been fully post processed with only a few machining marks present in places. I would fully expect the ESC to survive a crash and be able to pull logs if that is needed. It’s bulky and heavy though for placing inside a smaller aircraft. We did consider using these “naked” with a heatshrink wrap but decided against it to reduce how much work we do to a COTS product during aircraft integration.

The port cover is only really useful if CAN is not connected. Maybe having a 2 stage cover or separate plug for the USB to keep junk out during a crash?

The Instruction Manual

Fine. It’s slightly out of date, but things are moving rapidly with this technology so that is understandable. Maybe changing to a web based manual with an offline download option would be better.

The GUI

I did just download the version available on the website to check that everything I am talking about is still the same status. It looks fine and provides helpful buttons and tools to get and set all of the data. It works well and has yet to crash. It is quick to recognize the correct device when an ESC is connected.

There are no notes on what each setting does which means that you will probably need to reference the manual a few times to get up to speed on what each knob does. Each of those knobs has several detents, but the meaning of each of those is vague. In the manual several of these are very clearly a number, but that number is no where to be found in the GUI. Take Drive Frequency for example. The GUI has Precision, Dynamic, or Balance. I have to go look at page 6 of the manual to find that the numbers are 30-32, 16-18, or 8-10 kHz respectively. Why? The Drive Frequency setting is not alone in this regard. Put the number in the GUI. I’m paying for a high quality ESC. I know what each of these settings are supposed to be for my motor because motors are speced with numbers. Give me the number without making me reference a document.

It takes up a lot of screen space. Can this be made smaller somehow? It’s almost off the screen on some field laptops that have the scaling turned up for quicker reading of flight data.

Can this be signed software please? It makes the IT people nervous.

KDECAN

This is a rapidly evolving topic that might suffer from some convention issues from the initial release of KDECAN ESC firmware for a while. These ESCs use their own CANBUS protocol. That was at a time the UAVCAN and other CAN protocols were very new to ArduPilot and just making their way into the wild.

4.0 had intermittent telemetry. 4.1 seems to be more consistent. Numbering of ESCs starts at 2 (not 0 or…shudder…1) That will probably be weird until there is a breaking change.

Can we use DroneCAN in the future at the some point now that things are settling down a bit with the types of devices that are supported? That would allow for a single CAN port to be changed together with one of these ESCs as well as any number of other devices. As it stands right now, 2 CAN ports are needed with other DronCAN devices are present because mixing protocols is not allowed. That also puts a limit on the autopilot hardware than can be used.

TL;DR:

This is a great product. There are some fit and finish things that still need work with most of the issues I have with the product being solvable.