Looks more like a fork and report on the fork than a hijack to me. Assuming he started that project after 2 weeks ago. Makes sense to mention it here as it’s derivative. If the bad faith route–which is also perfectly reasonable considering we are speaking of humans 
--yeah hijack city.
Still, he is advertising his unfinished (presumably based on cfoc2) product on a CFOCv3 thread. Seems kinda weird to me. It’s like watching someone advertise their build on someone else s build thread without any additional added value to topic.
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The more people working on an open-source vesc that can handle 18s the better in my view. Also, it’s hard to see it as a “product”. As I understand it, the plan is to just release the schematics/BOM and pcb layout on github and let the community do what it wants. Watching both CFOC3 and F-of-C with keen interest.
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For the record, I lean more toward this take. Go forth and open source. I don’t have a problem with it although I do prefer any further discussion about F-Of-C then happens on that thread.
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Hey guys! I’m just getting into this whole thing partially because prebuilt VESCS are so expensive right now. I already got parts and PCBs ordered for cheap FOCer 2- and I’m very excited to begin the assembly. just a couple questions for anyone willing to answer: (A) I may or may not be planning on soldering the stm32 as well as the motor driver chip my self, for anyone whos already attempted this what are some suggestions and what’s the process? I do have experience soldering but I’m shaky. can it be done without a reflow station? (B) while I’ve seen a comment relative to this… I’m still a bit confused about the wireless interface. its got UART pinout correct? does that mean I could theoretically use any Bluetooth module (E.g hc05-06)? I want a remote so I’m not sure if that would be a 2.4ghz receiver then?
Hey, this is the thread for Cheap Focer 3, so it would be better to ask questions about the Cheap Focer 2 in this thread.
A) The STM32 is quite challenging to solder. Flux is a must and I would recommend a hollow tip like this. For the gate driver you will need a hot air gun. I am using this and it works fine.
It will probably be cheaper to just order the PCB’s with these parts already soldered on, unless you want the learning experience.
Here is a video of Benjamin replacing a DRV and this is a video of GreatScott attempting to solder his own VESC.
B) It has got a UART interface but the HC-05, … bluetooth modules are not supported. You need a bluetooth module with an nrf51 or nrf52. There have been a lot of reports lately of these modules coming from aliexpress not working correctly, probably counterfeit. So it might be better to buy one from trampa, or another reputable seller.
Remotes usually include a receiver that you connect to the PPM input, or somethimes to UART.
you can get vesc for 100$ from Mr.Bezos
People tend to forget what they’re paying for. Personally I’d stay away from any ESC at that pricepoint that I’m going to trust with my life.
The BoM of a vesc6 is roughly 85 bucks (pre-component crisis). Add a heatsink and some cables and you’re at the 100 USD mark. Sure, volume brings prices down. But I think the prices today very much reflects what you get in terms of reliability, customer service and warranty.
Compare the Vesc to lets say a curtis controller. The vesc is less then 1/10th of the cost. (while the curtis controller upholds alot more standards etc, buit you get the idea)
The cheap FOCer is a great alternative for the DIY savy but in most cases comes with time as additional investment 
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I’ve been using them with HC-05 modules plugged into the UART for a long time.
Hmm, also with the latest firmware? It used to be supported but I thought this was no longer the case. I haven’t tried it in a long time though
I’ve got it working with 5.2. Unfortunately, the protocol seems to change as firmware is upgraded. But the HC-05 modules just act like a wire in the end. So if you can talk to it wired, you can replace the wire with a pair of HC-05’s. I’m happy to share my code with anyone interested.
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one last question since I’m on a roll… I only got one remote/receiver kit and I plan on running two of the Cheap FOCers. I looked it up and saw someone mention a CANBUS port for communication/sync between the esc’s. does the cheapfocer have that? if not how would I go about running both ESC’s without 2 sperate receivers? I cant find the standalone receiver at the moment but I will continue my research.
Yes, it also has a can bus port, so you can connect 2 ESC’s together this way
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There are two ways to go, and each has their pros and cons. The simplest way is to simply make a Y-cable for the PPM signal that comes from your receiver. One branch of the Y will need power, ground, and signal. The other one needs only ground and signal. Do NOT bring a power line to both CFOC’s. Now your receiver plugs into both units.
Alternatively, you can control one CFOC with your receiver and control the other over the CAN bus. If you use the CAN bus, both CFOC’s have to be on the same power supply and come up together. Also, make sure and run ONLY the two data wires of the CAN bus. Do not run the CAN power and Gnd leads.
If you use CAN bus, you’ll also have to configure the CFOC’s accordingly.
@ziploc Could you clarify some of the pros/cons of dual wiring the remote vs CAN bus? If we’re using a UART based receiver do you have to use CAN bus or could we dual wire just the receiver UART TX? Is losing sync over CAN bus a common issue?
The upside to making a Y cable is that it’s simple, and in some ways more robust. If you have one CFOC fail, you can still limp home on the other (although you would have to swap the ends of the Y in the worst case depending on which one fails and whether you have to pull its power). One downside to the Y-cable is that you can occasionally end up in a situation where one is braking and one is in reverse if you’re using the reverse feature. Another downside is that you can’t do fancy things like traction control.
I’ve run both ways pretty extensively. I’ve blown enough stuff that I’ve decided to go low-tech for now and use the Y-cable. My board is an off-road board, and I carry a backpack with spares. The list of spares keeps growing. I’ve got nuts, bolts, bearings, chain links, tools, inner-tubes, and now I even carry a spare CFOC.
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@ziploc Interesting I found this at VESC Project while trying to find out more about Y-wiring vs using CAN bus between twin ESCs.
Never connect a receiver or other devices to multiple VESCs (e.g. Y-PPM). Use CAN-Bus instead.
Only connect CANH and CANL In the CAN connector. 5V and GND should be left unconnected.
Failing to follow these instructions may damage your VESC (s) permanently.
I assume the concern is creating a Ground Loop between the two VESC’s if the battery ground and the receiver ground aren’t the same. Although I could also see how without a solid ground between the ESC’s you could also experience loss of sync.
Yes, I think you want a common ground for battery, receiver, and both VESC’s. And my recollection (I don’t recall where I read it), is that both VESC’s should effectively be hardwired together for both power and Gnd. You don’t want one coming up before the other. Presumably, you could potentially push a ton of current through the CAN bus or the Y-connector otherwise.
without a solid ground between the ESC’s you could also experience loss of sync
I’m not sure what you mean by “loss of sync”.
@shaman I’m curious would a single microcontroller with two gate drivers instead of twin VESCs result in a significantly cheaper/smaller BOM/build for most, excluding one wheel applications?
@ziploc I’m coming from pre-built Boosted and Summerboard, so I’m still learning about DIY esk8 and VESCs. I saw this from @SpeedDemon and I’m not sure how common of an issue it is, but he had to swap out twin MakerX Go-Foc Minis for a dual Xenith due to CAN bus issues.
Having the two independent vescs turned out to be a bad idea. I kept getting CAN related issues where one esc would stop being detected and I’d have to do a firmware reflash to fix it.
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I’m certainly no expert on CAN bus, but following best practices (both VESC’s share ground, power up together, lift power and ground on the CAN bus), mine always seemed to work fine. One thing I never did get worked out is reading data from one VESC through the UART of the other. But I imagine I just had the commands wrong. In the end, that was a big part of why I went back to a Y-cable for the PPM.
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