dogshome

Model planes and helis (and cars) generally use brushless motors now. I know tanks don't use anywhere near as much current (and it's probably a daft question) but do tank drivers use brushless?

You could get some unstoppable climbing power and a very wide speed range [sm=confused.gif]

Norse

i think this was turned down before because the tanks need torque not speed

dogshome

The characteristics are very similar to DC motors, just more efficient?

heavyaslead

Brushless motors get their advantage from continous running usually at high speed, which translates to better efficiency.

Tanks typically start, stop and reverse often compared to cars on a racetrack or props in the air, therfore efficency and benefit is largely lost.

Planedev

Also reversable brushless motors need to be 'sensed' thus the reversable esc will be quite costly. Unless there is a cheap source of reversable BL escs out there I dun see how it will catch on in tanks.

patpatballball8888

That is exactly why brushless motors kept away from RC tank because of cost. I am no mechanic expert, but the speed can be transformed into torque via gear and its ratio. Am I right?

darkith

I think it's a case of:

Most cheap brushless ESCs are uni-directional (for planes/helis) and useless for tanks. Bi-directional ESCs are expensive right now due to limited volume/market.

Most brushless ESCs are sensorless because they're cheaper, but they stutter and lose torque at startup as they determine if they're running in the right direction, so they're useless for tanks. Some of the new truck ESCs have gone sensored for this reason.

Brushless motors are good for putting down lots of power without brushless/arcing. Tanks typically don't need lots of pure, raw power...they tend to need torque, so lots of gearing works just as well.

Tanks don't stress their motors very much at the low power levels (a couple of amps sustained), so brushwear is a minimal factor and the motors will last a long time. Can't say I've heard anyone complain about having to replace their tank motors frequently. Trucks/cars would normally be running in the dozens of amps and wearing brushes much more quickly.

Most of the electronics are built for brushed motors...so it's hard/more expensive to hook up brushless motors.

D.

dogshome

Thanks guys! I can't argue with any of that.

RC-Archer

I think that if you want to upgrade the motors, replace the 3 pole motors with 5 pole toy locomotive motors. The 5 pole motors runs slower with more torque. Maybe look for a motor used in a G scale train.

TexasSP

Just wanted to throw in that there is a lot of incorrect information posted in here related to brushless motors.

A)Brushless motors do not require sensors to have reverse, in fact most brushless systems are sensorless and use back EMF to detect rotor location
B)The cogging (stuttering) commonly referred to with brushless motors is virtually non existent today due to the advancement of software and hardware
C)Brushless motors create as much and more torque to any comparative brushed motor
D)Brushless motors are more efficient at all speeds low and high (some brushless motors have up to 99% efficiency, a brushed motor is hard pressed to reach 75% efficiency)

For the cost versus need I would not see the advantage of brushless motors in 1:16 and smaller tanks, how ever in heavier metal style tanks and in 1:6 and larger scales they would be very useful.

For the record I have been using brushless motors for 4 years in monster trucks and have a good bit of experience there. I need both torque and speed in my applications and brushed simply can't compare in any way.

For a good view of all the types of brushless systems on the market, check this site:

www.castlecreations.com

patpatballball8888

I did the experiment on my brushless motor for RC helicopter, and verify what your point. My brushless motor is sensorless and the speed controller is generic brand, cost for both is less than US20. There are 3 wires goes from the speed controller to the brushless motor, the motor will spin to one direction while if I swapped any 2 of the wires to the motor, the spin direction will be reverse. After all, what you need is a 'smart' ESC that can swap the output wires electronically to do forward and reserve.

TexasSP

I have three brushless speed controllers with built in reverse. There are several hundred models with built in reverse available. The reverse feature has been around for at least 8 years.

My speed controllers also allow programming of brake curves, throttle curves, drag brake (braking when letting off throttle), motor timing, start power, brake power, and several other parameters all via a PC interface. Brushless technology is top notch and has come a long way in the last 5-6 years.

patpatballball8888

Thanks for your info, since I just use the brushless on helicopter, so reverse is not necessary. and not realized ESC with reverse feature is available in market for long. Do you have a ball park price or any recommendation where I can buy those ESC?

** My speed controllers also allow programming of brake curves, throttle curves, drag brake (braking when letting off throttle), motor timing, start power, brake power, and several other parameters all via a PC interface. **

Yes, in that way, the motor behaviors will act more realistic to the actual tank/truck.

In my previous thread months ago, I already mentioned my intention to power the HL tank with Li-Po (already done) and brushless motor/reversible ESC, then I can use separated Rx with programmable Tx, with all the detailed settings on ESC and Tx, the HL will be running like a charm.

Planedev

I went to CC and also did a search on the internet for reversible BL ESCs, though it did not state if the motors and ESCs are sensored or not, the price for them are still in the zone of over USD$100. Which is why I stated that unless a cheap version of said ESCs are available to the masses, I don't see why BL motors and ESCs will be installed in tanks soon. Also with many ppl using the stock electronics of HL boards, intergrating the BL system will be complicated.

Lasty, we dun get much ppl complaining about wearing out the brushes on a tank, or sparking issues from the motors that causing performance of the tanks to drop, i.e. intermitten power, lacking of punch, etc... and if there is really an issue with teh motor and needs replacement, a replacement motor might cost you less than $10 if you know where to find them.

But seriously, has anyone changed a motor due to wear yet?

RC-Archer

I use brushless motors in my airplanes and helicopters and I have no complaints with using them there. There they're awesome!

The main advantage that brushless motors have over brushed motors is efficiency as well as no brush wear. But brushless motors are not very smooth at running at slow speeds. You will not usually find brushless motors in servos for example. So unless you're planning on taking off from a runway with your tank, I see no need for a brushless motor in your tank.

On the other hand, if you want smoother and better performance from your tank, you would be better off using 5 pole motors in your tank. You can still use the same HL boards. Look on eBay for 5 pole motors. I have a LGB Buhler motor that with a change of pinion, looks like a direct replacement. Unfortunately, I only have one motor.......

NoBrainer

On RC Crawlers, they use 55T motors, to get slow speed and high torque. Could those motors be used with tanks maybe?

[link=http://teamnovak.com/products/esc/55_turn_rooster_combo/index.html]Like this set from Novak[/link], it will cost you a lot of money, since you will need 2 of them and they are quite expensive.

I have tested with 480 Brushed engines on a HengLong Bulldog, with 2 Tazer 12T ESC's and the pure power is awesome!! The speed is now quite scale, I think I need some more teeth on the engine to slow the speed down, but the walker bulldog had really great torque.
If I could test with a brushless motor and ESC, I could compare the two, but right now I can't afford anymore parts...

I use a Futabe 10C 2,4GHz transmitter for my HengLong. My Tazer 12T ESC's are a bit "choppy" on the moves, so I don't think they are suited for the task.
Both ESC's can be programmed, but I only manage to "neutralize" one and the other ESC I need to use the trim's on. Can' quite get it to work the way I want it to.

But first of all I need a new hull for my bulldog, since the power from the engines tore off the front idler from my bulldog.

Planedev

Hi NoBrainer, how did you connect your 2 escs? Do you programe a sort of link in your TX to make it work like a vtail? If not, then probably you can try getting a vtail mixer circuit and connect itto your throttle channel and your steering channel. That way you can use one stick to move the tank forward and the other stick to steer her. That is off course if you have not already done that.

TexasSP

This not true as well. I can crawl with my brushless motor systems from dead stop as smooth as a brushed motor. I can crawl at low speeds and bring my 10lb monsters up to 45 mph with the throttle smooth as silk all the way. In the beginning there were smoothness issues, however those days are over. In fact many in crawling have been switching to brushless over the past several years. There are also crawler specific brushless systems.

I in no way said any of it was cheap and for small scale tanks they are not really needed. My main point was to correct the false information being put out there about brushless in general. Most people repeat what they hear with no actual experience.

NoBrainer

I fell for the BLING-BLING and went out and bought me a Futaba 10C FASST
Right now I don't remember how I set it up,but it was some sort of Aileron setup, the 10C got a hole lot of different setups so I had to check most off them out.
I can post how I did it later.

I use Aileron/Elevon stick to move my bulldog. The thrust/rudder is intended for turret and main gun. Works like a charm except for 1 ESC is stuttering a bit.
If it wasn't for the price, I would have bought crawler engines and esc's for brushless setup.

I haven't looked into turret movement yet, but considering a winch servo for boats, so that the servo can go 360. Using micro servo for the main gun elevation.

NoBrainer

My Futaba 10C setup just for driving a tanks.

I got 2 Tazer 12T ESC's. Connected to ch1 and ch2.
I got ELEV: Reversed (probebly because I have made a little mistake when I fixed the motor)
Setup with ELEVON Wing-Tail mix and I have changed the Rate-ail1 L:0% R:+80%, and Rate-ail2 L: -80% R: 0%

This is not a perfect setup but it works.
I havent gotten the time to check it further, because my front idler broke off...

I assume you have to adjust things your way if you use any other transmitter / reciver, but this is a lead in the right direction.

Dongskie

Dude NoBrainer,

You have to show me how you set-up the radio, i have a 9CHP from my heli and it's hanging around here waiting to be installed, as well my 2 esc's..

Good luck bro happy tanking!

NoBrainer

I hooked up my 2 ESC the way the manual said when I was to use Elevon Wing-Tail mix. Don't remember which channels, but read your manual.
Activated Elevon Wing-Tail mix.

RATE-AIL1 L:0% R:+80%
RATE-AIL2 L:-80% R:0%

ELE1: +100%
ELE2: +100%

I had to reverse the channel 2: Elevon, others are normal

This way I get to a kind of superspin. But not as much as original Heng Long.
I have 100% throttle forward, I reduce speed on 1 belt when turning.

Like I said I have used Tazer 12T ESC, but those "SU*KS". If your going to do this, I would buy some ESC that I could program, like the [link=http://www.castlecreations.com/products/sidewinder.html]Castle Creations Sidewinder 1/10 Sport[/link].
And then you need a [link=http://www.castlecreations.com/products/castle_link.html]programming interface[/link] for the sidewinder. The reason for this is that Tazer's responds weird. I don't like the way the break. I don't like the way they handle gain in throttle. If your having problems with stuttering and such, you might need a BEC, and the [link=http://www.castlecreations.com/products/cc_bec.html]CC BEC[/link] is a good choice.
With the Sidewinder, you can controll this much better. AND Sidewinder can use both brushless and brushed motors, so you don't need to buy another ESC if you want to use it in a stadium truck or what ever you like...


Note!!

Brushless motor connected to the sidewinder makes a lot of noises when you change direction or stop or start. I didn't like sidewinder with brushless because of the noise. But with a brushed motor it is so smooth and great.

Planedev

Just too bad it will be too complicated to add these nifty toys in a Tam or HL tank.

NitroAssassin

i run brushless hardware in my r/c trucks/cars and believe me the torque is unreal.. Brushless motors have more torque than brushed motors, no comparison.. Brushless motors can take alot taller gear ratio than a brushed motor because of the torque.. I've been into R/C all my life and until I experienced brushless motors combined with Lipo power i couldn't believe it. I have a stadium truck that will do 70mph, it will begin a wheelie at 50+ mph and get 40+ mins of runtime on a single 6000mah 11.1v lipo battery.. I can't even imagine trying to run something like this in a HL tank lol The reduction would have to be insane to calm down the top end, and the torque of those motors would really put a strain on the drivetrain.. If you're having track problems now you would be trashing alot more with brushless power..

If anybody is interested in seeing a video of a brushless setup in action I can post a video of a 70mph run I did this past summer... just to give you an idea and idea of the torque and hp. [8D]

swathdiver

I always thought it would be cool to do fish tails and jump ramps with my BullDog at 10mph. Brushless is the only way to go to do that. I cannot imagine the cost though! [:-] Post the video link if you have it, everyone loves videos!