Sensored Outrunner motors- Revolver S

[JohnRobHolmes]

I have been playing with sensored outrunners a bit lately and happened to run across a guy who is building his own sensored DC motor controller, and he is also converting a large outrunner to sensor based commutation since it is easier than building a sensorless controller.

I took apart a Tekin sensored motor today to find that it uses 120 degree separation of hall sensors. I also ordered some sensors from digikey http://search.digikey.com/scripts/Dk...me=480-1999-ND

Hopefully I can fit the sensors between the teeth on the stator with no modifications. I don't know if I will use a Revolver Black motor or the Crawlmaster first. At any rate, this will be a good long term project. Here is the diagram that was made to determine where the sensors should go on the larger outrunner, he used 45 degree spacing. On my motor they will be spaced 120 degrees apart and placed between each phase, this will allow for universal endbell changes in the future.


This is all new research for me, so I am going to hope for a bit of luck on this. I will use the Tekin RS speed control for first testing. If this pans out we could have sensored outrunners!


Edit: Look for pre production pics, page 10!

[Tupers]

Hmm most of that went right over my head but it sounds like and interesting idea. What would be the advantage of a sensored outrunner??

[Rockpiledriver]

Originally Posted by Tupers

Hmm most of that went right over my head but it sounds like and interesting idea. What would be the advantage of a sensored outrunner??

No cogging and huge amounts of torque.

[JohnRobHolmes]

HUGE amounts of torque. Inrunners typically spin 50k or 60k max. Outrunners typically spin 10k. Same power for the same weight, but the outrunner produces the power at a higher torque value.


I have two different sensors on the way now. One of em will fit right in the teeth of the crawlmaster. Score for part one!

[mysharona]

If you pull this off, this will make me go brushless!

[Mnster]

It all has to go within the can not designed around it, man that is going to be tight. Super cool idea though I love tinkering with electronics, I'll be watching this thread for sure.

[JohnRobHolmes]

This is not my pic, but this is what I will attempt.

[EGRESSor]

Plettenberg has used optical sensors
should work with outrunners too

[TheHeadHunter]

I understand about %30 of what you are on about ...looks mega exciting
hope you come up with the ultimate crawling motor

whats different with having sensors?????



best of luck !!!!

[JohnRobHolmes]

Sensors will allow lower startup speed for brushless motors.

[brushlessnut]

will this be like running a hall sensor in a car? if so what do you plan to do to help cut down on singal nosie im droping tach singal from my hall sensor at 6,200 rpms in my drag car i was told to put a 10k resistor in line with the VR signal..from my under standing of the hall sensors these will be almost the same as what is in a car but with a wider nosie pickup ?

[Nick77]

could i send yuo my bm 16 brushless and you do that to it for a fee?

[JohnRobHolmes]

Originally Posted by Nick77

could i send yuo my bm 16 brushless and you do that to it for a fee?

I don't know yet, but it should be possible.

[Stormin2u]

That smooth controlable sensored start up on a outrunner would put them back in the crawling game IMO.

[Nick77]

sweet, i will keep in touch with you about this.when do you think you might know when you could do it

[Reflection]

Originally Posted by TheHeadHunter

hope you come up with the anotherultimate crawling motor

Fixed it for you.

Hey John,what do you think the sensors would do for my 3025? Adding sensors to a certain motor,wouldn't change the wheel speed and power levels at a given gear/voltage would it? Your not changing the winds or physical size of the arm. I can see how the sensors will make it allot smoother on start up.

[JohnRobHolmes]

I don't know time frame, first I have to get the sensors in. I ordered them yesterday, why aren't they here yet???


Nothing will change about performance, except the slow speed startup. This should bring the average outrunner motor from 200 to 500rpm startup down to 10rpm or so, depending on magnet strength and consistency.

[Nick77]

joh the pic you posted of the motor, where did you ge that? that is a bm 16 brushless,someone has already done it.so we know mine can be done

[Reflection]

Originally Posted by JohnRobHolmes

I don't know time frame, first I have to get the sensors in. I ordered them yesterday, why aren't they here yet???

Dude,I'd be pissed. They should have been there right after breakfast.

Originally Posted by JohnRobHolmes

Nothing will change about performance, except the slow speed startup. This should bring the average outrunner motor from 200 to 500rpm startup down to 10rpm or so, depending on magnet strength and consistency.

Thats kinda the way I was understanding it. Smooth starts even at taller gearing???? That would be AWESOME! May have to dust of my outrunners again.

If I send you my motor,could you add sensors and get it back to me before our comp tomorrow?

[brushlessnut]

so dose a smallr hall sensor make it pick up less rmps..i know the one im running in my car will only pick up 35rpms and up non the less i still got some brushlessmotor that will need to try this when you get it worked out