Limitations of sensored motors?

Why is it that all the high torque high watt, low kv motors that you 8th scalers use are all sensorless? Why don't you see (m)any in sensored? Is there something with the design of a sensored motor that limits its capabilities? Or is there just not enough interest in them to justify building and marketing them? I'm assuming the novak HV is sensored, and I know they and LRP cater mostly to 10th scale racers and the sort. Also in some other forum, I was detailing what I have planned in my stampede build which included an lrp a.i. with a x-11 9.5 motor. Anyways someone listed one of the cons of that as it being sensored as well as underpowered. For what I want to do with the stampede, I really don't want that much power, but whats wrong with sensored motors? I have a mamba max system and I have this, though not running yet, sensored setup, and I have driven a few sensored setups and absolutely love the smooth control of it. So I'm confused, why is sensored considered a flaw? I wish castle would incorporate a sensored port with their speed controllers as I wish my mamba had the smooth take offs and low speed controllability that sensored systems have.

[tc3_racer_001]

well, thats where the mamba max pro comes in... complete with sensor port...


the reason why?? simple (in my eyes anyway, im no expert, if it works it works if it doesnt, try something else attitude) is ALMOST ALWAYS better. with sensored, u need a bit more stuff in the motor (sensors etc) and u have an extra wire to deal with. if you can get the same performance without these, WHY NOT???

sensorless were first made for planes and smoothness on startup (where sensored is sometimes better) isnt an issue at all... and there were no manufactures making sensorless/sensored motors for electric cars... so people naturally used the only thing available, for the better or worse :) since then sensored has (for some dumb reason) beed accepted as the racing standard... perhaps sensorless was too good :P

anyway, we are just using motors designed for planes and controllers (originally) with modified brakes and essentially the same hardware.

now there has been a revolution and many choices are available, but so far the efficiency and the KISS method are top priority, i dont care if its the slightest bit rough on startup and at crawling speeds, when will you be doing that on a racetrack!

ryan

The issue isn't whether the motor is sensored or sensorless in terms of power output. Aveox made some very powerful sensored motors when they were still in the RC game.

The problem is that motors like the HV4.5 and HV6.5 appear to be based loosely on their little brothers (ROAR legal motors, which have design constraints). These ROAR designs seem to be pretty power limiting (I don't know if that's because of the iron stator, wind type, or rotor size, or perhaps a combination of these three or even more variables; their tiny rotors don't exactly help with torque output though).

The best option I've seen so far is hybrid systems in terms of sensored vs. sensorless. I believe the Mamba Max Pro will be doing something like this, and ESCs like the Speed Passion GT ESC also use this. This way, you get the best of both worlds (low speed driveability and cog free operation, coupled with variable timing once the motor gets going that is associated with sensorless systems).

[zeropointbug]

I would think a purely sensored controller would be simpler than a sensorless controller... mainly because you wouldn't need all the "sensorless" sensors (IC's, etc). I honestly wouldn't mind having a sensored Neu over a sensorless version... heck, it would be ZERO cog, run with less issues, and maybe even more efficient?

Exactly. Obviously its the market then. You're using motors not specifically designed for cars, so why implement a hall sensor? But now that large scale vehicles are becomng more popular and you got companies releasing high current escs to do the job bundled with motors, why not redesign it with a sensor plug. Is one little wire really that much of a hassle? Maybe with the voltages you're running, you don't notice that much cogging, but I prefer the smoothest startup possible.