So needing temp sensors is the kind of thing I was asking about earlier for understanding the hardware dependencies for ASS. Is it really a requirement or is it just something that helps?
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https://vesc-project.com/node/2859
I’ve also asked for technical details on the vesc project forums so that maybe Ben can provide answers for this kind of stuff. I have yet to receive an answer. @Trampa I understand he is massively busy but can you ask him to post some of these technical details in a public space so that we know what we’re dealing with and how to properly test it? It will help our quality of feedback if our testing approach is solid.
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I tried it on an old VESC 4.12 and it wasn’t really working at all. Using HFI tracks the motor a lot better. I was also wondering if I have done something wrong, but looking at the results @tipsy gets with the HD60T that is advertised being A.S.S. ready and also not working that great I came to the conclusion that it isn’t ready yet.
I would love to see a video from Benjamin like he has done about HFI where you could see what performance can be reached. Maybe me and @tipsy are just doing something wrong and it really is a lot more advanced, we just didn’t set it up correctly.
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So much this
My experience with HFI though is that the tuning is extremely sensitive to motor temperature, so maybe they’re using temperature in the maths to make this work.
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Temperature-sensitive features most likely need an accurate and somewhat real-time Resistance measurement and can theoretically be kept happy with the temperature compensation. There’s a pretty linear relationship between motor temp and motor resistance.
Maybe some kind of function could be made that measures motor resistance at a known(user inputted) motor temp. Then the controller can do temperature compensation from then on assuming this linear relationship. I think there was talk of this but I’m not sure
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A.S.S is senstive to the motor temperature, since the resistance changes with temperature. There is also a method to catch the motor temperature via HFI bleeps, but temp sensors are the way forward at this stage. They are easy to add to non sensored motors and two thicker temp sensor cables are a lot less likeley to fail than 6 thin and fragile wires. Also fixing a broken temp cable is a lot easier than a six wire hall cable. For initial tests I upgraded a non sensord motor with an off the shelf 10K ptc on a cable. Took me 15minutes and a smile…Another advantage is that broken or shorted Hall sensors can take down a motor controller, a broken temp sensor will not do that.
After coding a little HFI bleep into the A.S.S code, BV confirmed that he can now get perfect startup in every single try. An updated Beta software will be available soon.
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I agree that two extra wires are better than six extra wires, but still a lot worse than zero extra wires, which the name “sensorless” implies. Statements like the following and having a “sensorless” in A.S.S. is just false advertising at that point. Something you criticize on a lot of VESC based controllers.
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Can you explain that? When the 5V that is needed for the Hall sensors short to ground its the same damage like when the 5V for the temp sensor shorts to ground.
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Frank, any good source on how to do this?
might aswell go with sensors at this point
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In the mobile version, is there no way to enable live packets (heart) so i can run foc_openloop?
The Issue with a broken motor sensor is not the risk or bringing the 5v rail down, its the risk of getting an incorrect position reading and trying to drive the wrong motor phases as a result. This cause cause huge currents through the ESC which can damage fets or blow the DRV.
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In theory yes, but in practice the Hall PCBs and hall hall probe legs were more likely to short out than a simple probe that is pretty well insulated and uses thicker and more sturdy cables. Also there are 3 Hall probes vs. one temp probe. And there is a 10K resistor in the Temp line while PIN 6 of the SESNS port has a direct connection to 3.3/5V.
Second problem with sensors is the wrong signal reading they can give and that can cause potentially HW damaging effects.If we can save away causes for trouble, it is a good thing. One part less to worry about…
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sturdy wires probably doesn’t help with temp sensor noise, which is the reason a lot of us have disabled the temperature sensors.
I may have misinterpreted, but felt like jeff was just saying, with a lot of motors… we’re just f’d. 
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Simply cut the wire and glue the temp sensor to the front side of the coils for example. Running the sensor cables above the spools is no good idea. Our motors had the hall pcb in front of the spools to avoid this issue. Fast spinning stong magnets above a wire carrying a signal is not the best design choice. Riding without temp feedback is also no good idea.
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A new beta software is online: Firmware 5.03 | VESC Project
Sensorless startup should now be almost perfect if it’s a VESC HD or VESC6MKV or 75/300.
It also features a new wizard for e-skateboarding.
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I‘m not sure if it wasn’t already addressed before, but I very often have issues to setup my vesc based escs via can.
Mostly when starting the input wizard I get the „all vescs need to have the same FW“ message, which doesn’t allow me to go further with the setup.
Switching on of the escs, starting the vesc tool new or switching the esc I’m connected to usually fix that.
I do have this issue with all kinds of vesc based escs as well as with a set of vesc 6+.
FW is 5.1, not yet ready to change to a newer version 
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This is exactly what I’m getting trying to do detection with the new 5.03
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So “HFI Start” mode is sensorless + a little HFI blip?
Do I have to do any of that annoying HFI tuning process for it to work as intended?
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