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It's odd how technology moves to different hobbies at different times.
Here's a reference to a sensored brushless RC aircraft motor from Jan, 2002. It changed the entire RC aircraft industry overnight. That, plus Lipo batteries.
https://www.rcgroups.com/forums/showpost...stcount=60
Sensored brushless electronic speed controllers have always had 3-wires to the motor, and 2-wires to the DC battery.
I have no clue who that "Ken" guy is.
By the way. The brushless motors made those little warbird go straight vertical out of my han... er, that Ken guys hand.
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(4th-Jun-25, 11:09 PM)KensRedZed Wrote: It's odd how technology moves to different hobbies at different times.
Here's a reference to a sensored brushless RC aircraft motor from Jan, 2002. It changed the entire RC aircraft industry overnight. That, plus Lipo batteries.
I remember the first brushless/LiPo setup I bought, although it was unsensored my first reaction after driving for about a minute "this is a game changer, there's no going back"
...and so it came to pass
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(5th-Jun-25, 07:17 AM)Kevan Wrote: (4th-Jun-25, 11:09 PM)KensRedZed Wrote: It's odd how technology moves to different hobbies at different times.
Here's a reference to a sensored brushless RC aircraft motor from Jan, 2002. It changed the entire RC aircraft industry overnight. That, plus Lipo batteries.
I remember the first brushless/LiPo setup I bought, although it was unsensored...
Sounds like an X-rated film that hasn't been graded yet. You mean sensorless?
The very first brushless were sensorless. However, they were very small and harmless (almost. I still have one old clunker). You had to gently increase the throttle at first until the prop stopped dancing back and forth in both directions. The worst that could happen is the prop came loose.
The moment the large brushless motors started to hit the market. They had to be sensored or they could break the prop blades right off with the violent jerking back and forth.
All brushless ECS's in RC aircraft were sensored shortly thereafter. No more props unscrewing themselves from the main shaft mid-flight. Yay! Flying a P-51 Mustang dead-stick without a prop sucks.
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I said unsensored not uncensored
Those early ones we just called brushless motors it was only after the sensored ones became available that we started using the word unsensored
Sensorless/unsensored....potato/potato... tomato/tomato... It's the same thing.
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Can’t beat the simplicity of a DC motor and 2 wires. I think brushed motors will always have a place.
As for sensored/unsensored I wonder if you could use back EMF to detect timing, instead of an extra PCB and wires as mentioned?
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I'm sure the manufacturers would have used the cheapest/simplest/best options available already
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I was thinking probably but then I just googled “using back emf to detect timing on brushless motors” and apparently it’s possible.
I wonder if 3 wires will suffice and a purpose built ESC to suit can adjust the timing as dialled, essentially using the PCB to do the work based on BEMF detection and so no actual sensors in the motor are required? I like wiring to be as simple as possible.
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If you could integrate that into a digital chip you'd have a world first...and digital racers are already looking for this.
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It would be a pretty deep project overall and I already have enough on. It would be interesting though.
The MPD was kept single sided so all the extra BLDC components could go on side B. We have BEMF detection circuitry in place on the MPD, however it would need to be duplicated again on side B specifically to suit the brief.
Brakes and throttle map are in the Scorpius throttle. Frequency and timing could be set using the app.
You could also place a hall sensor on the brushless motor and plug it into one of the data ports on the MPD to detect timing pulses. I suspect the firmware for this would be pretty deep though with a lot of trial and error work (read time), but would be pretty cool.
It’s also technically possible to analyse the various aspects of the motor, ie torque, power, revs using the MPDs BEMF detection and perhaps the hall sensor could find a role also, ie wheel sensor.
So the MPDs potential diagnostic capabilities could one day be useful in testing and configuring the system to help speed up development.
The day will come where brushless become the norm and such a chip will be required. When that time will be is still unclear.
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It will become the norm if a £75 Slot car is still £75...I suspect with brushless and Ecom that's going to be nearer £150 in which case it won't become the norm but as a racing upgrade why not, it's already happened.
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