IFMAR motor rules for brushless [Archive]

e_lm_70

08-26-2005, 07:07 AM

Hi:

Here are the rules from IFMAR ...
--------------------------
d) `05` size specifications
Can:
Overall maximum diameter is 36.02mm measured at whatever point yields the maximum dimension, excluding solder tabs or lead wires. Overall minimum diameter is 34.00mm measured at whatever point yields the minimum dimension, excluding solder tabs or lead wires. Maximum length is 53.00mm measured from the mounting face of the motor to the furthest most point of the end bell, not including solder tabs, lead wires or original manufacturer’s logo or name. Minimum length is 50.00mm measured from the mounting face of the motor to the furthest most point of the end bell, not including solder tabs, lead wires or original manufacturer’s logo or name. Motor mounting holes must be on 1.00- inch (25.40mm) centres.

Stack/Stator:
Stack minimum length 19.30mm, maximum 21.00mm. Stack inside diameter minimum 12.50mm, maximum 16.00mm. If a stack is used then it must be continuous. The laminations have to be one after the other without anything in between. The thickness of the stack plates is 0.35 +/- 0.05mm. All laminations must be of the same material.

Winding:
Only three slot (phase) “Y” wound stators are permitted. No delta wound stators allowed. Only circular (round) pure copper wire permitted. No turn limit.

Rotor:
Shaft diameter must be 0.125 inches (3.175mm). Only one piece, two pole bonded Neodymium or Ferrite magnetic rotors are permitted. Magnet minimum length 23.00mm, maximum 27.00mm. Magnet minimum diameter 12.00mm, maximum 5.50mm.
-------------------------

Anybody knows which brushless sensorless motor is compliant with these rules ?

Differently then ROAR, there is no more limit on winding turns ...

But still the sucking Y rule .... anybody know the technical reson of this Y rule ?

e_lm_70

kufman

08-26-2005, 08:03 AM

According to those rules, only Wye wound motors are allowed (although they call it "Y" wound). That pretty much means that only the novak motors and the Reedy motors are allowed. :-(

masterdummy

08-26-2005, 08:17 AM

what does IFMAR stands for?

Jev

08-26-2005, 12:07 PM

International Federation of Automobile Racing

ElectricThunder

08-26-2005, 12:12 PM

International Federation of Automobile Racing
What's the "M" supposed to be though?

CharlieS

08-26-2005, 12:48 PM

Model

kufman

08-26-2005, 04:06 PM

But still the sucking Y rule .... anybody know the technical reson of this Y rule ?

Some claim that the y-wound motors have a higher torque constant for a given motor geometry. Some also claim that the 3rd harmonic current seen by the controller is lower. Probably the real reason is that they are easier to wrap. I have two different WYE wound motors, and I don't see an advantage in either of them. I also own several DELTA wound motors and they are my best motors (basic 4200, mamba, Pletty Shadow, Feigao 10L). The rule doesn't make a lot of sense for another reason, all current production brushed motors are DELTA wound! I made a WYE wound brsuhed motor, it is possible, but I don't know why you would.

SpEEdyBL

08-26-2005, 06:49 PM

It seems to me that the only difference between wye and delta are the connections between each coil. They're are near the shaft end of the motor making an extra half wind. All wye wound motors have half winds, right? The laminations have nothing to do with whether it's wye or delta.

kschauwe

08-26-2005, 06:54 PM

From Aveox:
""Wye" wind Motor

Draw 3 resistors (or coils) radiating from a central point (The Wye tie). Label the three ends A, B, and C. These represent the three phase connections in the Wye motor.

In the controller, each of these has 2 pair of MOSFETs connected to it, a pair to source the current, and a pair to sink the current. The motor fires like this (simplified for clarity) A-B, A-C, B-C, B-A, C-B, C-A ad nauseam. The Magnets "chase" the rotating magnetic field. Notice that there are always 2 phases "commutated" at the same time, but the mix differs, and the current direction will reverse every other time. The motors resistance is the sum of any two phases i.e. measure from any 2 phases. The third phase is open electrically when any other 2 are commutated.

"Delta" wind Motor

Draw 3 resistors connected in a triangle (delta). Each of the vertices is a phase. When you commutate CA-AB, you get most of the energy on one coil, (A), but some on (A-C-B) side. (mostly imo losses). The net result of most of the current going through one set of coils at a time, instead of two is that the Kt <torque constant (tm)> is cut in half and Kv <motor constant, RPM/volt (tm)> doubles.

At Aveox, we have essentially deemed the Deltas as secondary to Wye winds in any application, except where a very high degree of uniformity in both directions is very important. Things like robots that move in both directions equally put up with the efficiency losses. Since the motors are very insensitive to timing changes (unlike the Wye winds), you don't have great performance in one direction, and poor in another(without adjusting the timing). You have good performance in both. (but it is not worth the losses in a model)

They have been discontinued at Aveox for a couple of years. We do what we can to get them out of circulation by changing them over at a loss. "

SpEEdyBL

08-26-2005, 07:11 PM

Interesting, but wouldn't that mean you would have to double to pinion size for wye wound motors to compensate for the rpm loss and torque gain?

sugs

08-27-2005, 02:06 AM

Didn't Mr. Novak say in a post somewhere that wye wound brushless motors were easier to "tech" than delta. I can't remember exactly where but I thought he said something like that. Could be wrong.

kufman

08-28-2005, 06:27 PM

sugs

08-28-2005, 10:31 PM

Yeah, doesn't make sense to me either.

jocktheglide165

08-28-2005, 11:02 PM

you guys are so technical how come you guys aint on the board making the brushless rules not being rude, but I dont know forums members seem to know more than the IF dudes probably got their due to political reasons not technical reasons?

Jev

08-29-2005, 04:50 AM

It sounds like wye=more tourque. That's much more important to cars. So it's good that we are braking away for the airplane motors that were never intended for cars.

Basically the bottom line is this: Aircraft manufactures don't care about the car racing scene. Otherwise they would have anounced a new legal motors in the works.

dj_ski69

08-29-2005, 05:18 AM

bottom line is this:
Both ROAR and IFMAR have both become far too political than technical....
Already this year we have seen how far ROAR is willing to bend to appease the corporate world and certian manufacturers!
Unfortunately the R/C industry is no longer just a hobby...just like football is no longer a game...thiere both just plane old buisiness'
ROAR is coming to the point of living out its usefullness....

On the other hand...Thank goodness there are still sensable track owners out there who can see through all the BS and let brushless be brushless...
These guys are the ones who matter most...Its up to them wether or not brushless motors can or cannot be ran in thier prospective races....
There are more local racers than national or regional big races....
I have not seen any track owners who weren't so completely ingorant as to not let people run there BL setups in whatever class they could best fit them in...
Remember we are in this for the FUN first....And without the FUN there is no hobby at all...

SkI

masterdummy

08-30-2005, 03:39 PM

I am lucky all track owners in my area let brushless race in mod class against 8T, 9T and mostly 10T usually a brushless guy finishes in the top 3 or 4th place at every meeting I have even finished 2nd in one of the heat races!

kufman

08-30-2005, 04:50 PM

At our local track, they allow any brushless to run in Open Mod. It works out pretty good. With my Shadow/U-froce combo I can usually place in the A-main (almost won it two weekends ago).

Video 20MB

http://www.kufman.com/img/Stuff/car_pics/AJs%202005%20Divx2.avi

I am Matt and I run the Red and White "VanHalen" body.

BobNovak

08-31-2005, 07:37 PM

I think some of you are missing the point here on why ROAR and IFMAR exist. The basic reason is to have a uniform set of rules that can be used and applied at ROAR or IFMAR sanctioned races. This gives a level playing field for all those racers that chose to participate in any of these sanctioned races. Remember these organizations are run for racers by racers. If you are not a member do not complain. If you are a member you have every right to complain, but you should do it in a constructive manner. Either talk/write to your reginal director or contact ROAR directly via E-mail. Better yet become very active and run for a position in ROAR.

Bob Novak

BobNovak

08-31-2005, 08:18 PM

I don't see how teching would be any easier on a wye connected motor. Three wires, three poles. If anything, wye would be harder since there is the potential for a 4 connection on the "common" terminal.
The main reason for choosing to have only one type of wind was to make technical inspection easier, especially if you use an inductance meter to determine the number of turns in the motor without tearing it down. As far as which type is better, Wye winds are simply more efficient than delta winds and that is why we chose to use them.
Bob Novak

sugs

09-01-2005, 01:15 AM

OK, I think I get it. Wye is more efficient, and from some of the talk around here it sounds like its a better choice than delta for cars because of the torque characteristics. Also, only allowing for ONE type of wind in the rules is what makes it easier to tech, because the person doing the teching doesn't have to determine if its a wye or delta wind before testing for the number of turns the motor is. Right? I'm assuming you have to use two different tests to determine turns for the two different winds.

e_lm_70

09-01-2005, 04:04 AM

The main reason for choosing to have only one type of wind was to make technical inspection easier, especially if you use an inductance meter to determine the number of turns in the motor without tearing it down. As far as which type is better, Wye winds are simply more efficient than delta winds and that is why we chose to use them.
Bob Novak

Thanks Bob,

Can you calrify me two points:

- Since the number of winds is open/free ... I don't see the mention advantage for technical inspection.

- Based on what are you saying that Wye winds is more efficient then delta ... based on the data from Lehner motor it look like the opposite:
1515-delta (http://www.lehner-motoren.de/diagramm/1515-15.9v_liste.txt)
1515-wye (http://www.lehner-motoren.de/diagramm/1515-15.9s_liste.txt)

In summary these two motor are identical, just with different winding type and tested with same voltage:
The delta offer a best efficiency 84.7% with a power of 158,8w ... still offering a good 82.9% at 300w mark.
The Wye offer a best efficiency 83.0% at 75.1w ... and is already down to 73.5% at 150w.

With same amount of wind the delta is twice more powerfull then wye ... and still more efficienent !

Thanks

e_lm_70

kufman

09-01-2005, 05:49 PM

- Based on what are you saying that Wye winds is more efficient then delta ... based on the data from Lehner motor it look like the opposite:

Is there data for a 15 series wye wound motor that has the same rpm/v as the 1515 delta? It would be interesting to see data for two motors with the same rpm/v with the same can geometry (15 series for example).

BobNovak

09-01-2005, 06:12 PM

Thanks Bob,

Can you calrify me two points:

- Since the number of winds is open/free ... I don't see the mention advantage for technical inspection.

- Based on what are you saying that Wye winds is more efficient then delta ... based on the data from Lehner motor it look like the opposite:
1515-delta (http://www.lehner-motoren.de/diagramm/1515-15.9v_liste.txt)
1515-wye (http://www.lehner-motoren.de/diagramm/1515-15.9s_liste.txt)

In summary these two motor are identical, just with different winding type and tested with same voltage:
The delta offer a best efficiency 84.7% with a power of 158,8w ... still offering a good 82.9% at 300w mark.
The Wye offer a best efficiency 83.0% at 75.1w ... and is already down to 73.5% at 150w.

With same amount of wind the delta is twice more powerfull then wye ... and still more efficienent !

Thanks

e_lm_70
If you look at that same motor in the Wye configuration at a higher voltage where the power is geting close to the Delta wind you will see that the efficiency of the Wye wound is 85.1%. You have to look at equal power ratings. An X number of turns of a Delta wind motor will always have a higher power output than an equal number of turns from a Wye wound motor. The other thing that comes into play here is that the Lerner Motors have a lot more electrical poles than the three pole motors that we are using and thus do not suffer as much from that third harmonic. Don't get me wrong, there is nothing wrong with the way these motors are built. As a mater of fact the German Brushless motors are some of the finest motors made. What we are trying to do with the style of motor that was approved by ROAR and IFMAR was to make a motor that was as close to the existing brushed motor that was already being used in these organizations. Even with this we are getting a lot of resistance from the traditional motor manufacturers.
Bob Novak

kschauwe

09-01-2005, 07:04 PM

Even with this we are getting a lot of resistance from the traditional motor manufacturers.
Bob Novak
hmmmm....Like Trinity :D

masterdummy

09-01-2005, 10:20 PM

I tell you what man... now that I have tried brushless motors I don't think I would ever want to go back to run brushed motors anymore... :)

e_lm_70

09-02-2005, 04:47 AM

If you look at that same motor in the Wye configuration at a higher voltage where the power is geting close to the Delta wind you will see that the efficiency of the Wye wound is 85.1%. You have to look at equal power ratings. An X number of turns of a Delta wind motor will always have a higher power output than an equal number of turns from a Wye wound motor. The other thing that comes into play here is that the Lerner Motors have a lot more electrical poles than the three pole motors that we are using and thus do not suffer as much from that third harmonic. Don't get me wrong, there is nothing wrong with the way these motors are built. As a mater of fact the German Brushless motors are some of the finest motors made. What we are trying to do with the style of motor that was approved by ROAR and IFMAR was to make a motor that was as close to the existing brushed motor that was already being used in these organizations. Even with this we are getting a lot of resistance from the traditional motor manufacturers.
Bob Novak

Thank Bob,

I did some research in the last day on internet, and it look like that there is a common agreement that wye and delta have the same top efficiency (assuming that both are build up at their best) . Strange stuff is that lehner motor seem to work better in delta mode. But this could be a lehner specif issue.

From what I can see, it is more easy to get high RPM per volt with the delta motor, and high rpm per volt is something nice for RC car (since the power control is more smooth).

Actually I don't see any technical reson for avoid delta motor in the IFMAR and ROAR.

e_lm_70

P.S: BTW Lehner motor are 2 pole motor (at least the 15xx, 19xx and Basic xx). Every motor, brushed or brushless (delta & wye) have better top efficiency with higher voltage.

P.S: It would be nice to allow in IFMAR & ROAR all generic motor brushed and brushless ... anyhow it is not the +/- 50$ of the cost of the motor that make any difference in the cost for partecipate to a race ! Keeping the limit to 6 NiMh/NiCd cell, this is already a limit on allow similar power among the competition !

Finally: The BL story in ROAR/IFMAR is an half empty glass story ... you can see in a positive way : thanks to Novak now it is possible to race also brushless in the car competitions ...or in a negative way: since Novak dictated the BL rules, then only specs friendly to Novak have been accepted (all the BL motor present in the market, a part from the Novak, have been defined as not legal !)

Jev

09-02-2005, 02:04 PM

I think a manufactures name stamped on the motor would have been in the rules even if Bob hadn't specified it. So all the other motors would have failed on that anyway.

nicholcgn

09-02-2005, 05:15 PM

Well I think that no matter who was first and had some specs that worked their system someone would be mad. Bottom line is that some of the vendors worked with the existing bodies and got the ball rolling. Someone has to be the bad guy in every new catagory. The rules will change over time.

My thanks goes to companies that have worked with to get it started. I think the systems will snowball and in 5 years they will be the dominate force.

To anyone who does not like the specs - work to get them changed. If enough of the racers want it changed it will happen. Just be careful because you may get what you asked for and more.

All orginizations have the duty to look out for what is the best for the user of their product. Roar and ruling organizations are no different. The great news is we are finally seeing some results. I am sure it will not be long before other styles of systems appear. If there is money to be made somone will fill the void.

CharlieS

09-06-2005, 07:34 PM

Its not about the efficiency, its about the power. At the same efficiency you get twice the power. At least from the chart I was looking at. You make more power you go faster. One style is completely different power from the other, so they aren't permitted. Also, this prevents each Brushless Manufacture that is Comming into the Car Market from having to make two different designs. The sensorless style manufactures really have no interest in the car market, if they did, they'd make sensored systems. :)

kufman

09-07-2005, 08:24 AM

The sensorless style manufactures really have no interest in the car market, if they did, they'd make sensored systems

There is a sensorless brushless in this race, bet you can't tell which one it is.

http://kufman.com/img/Stuff/car_pics/Race%20Start.wmv

tcolesen

09-07-2005, 08:43 AM

The sensorless style manufactures really have no interest in the car market, if they did, they'd make sensored systems. :)

I would have to disagree. If this were true, then could you explain Castle Creation's development of their controller that isn't even out? It should be so smooth that it is just as smooth as sensored, except on cheap batteries (that will make a rough ride for any sensorless system). And how about the U-Force. That controller is very smooth. It is "the ultimate 1/10 racing controller." The MGM controllers have a very good setup, and MGM is working to improve their controllers.

The only difference is that these manufacterers are not geared toward racing (as in ROAR and IFMAR) as much as sensored systems are.

masterdummy

09-07-2005, 08:58 AM

There is a sensorless brushless in this race, bet you can't tell which one it is.

http://kufman.com/img/Stuff/car_pics/Race%20Start.wmv

wow!!! can we see the whole race? I would like to say the sensorless system is the redish/orange car was quick on the start!

Rtsbasic

09-07-2005, 09:07 AM

Mtroniks make car BL kit. Its specifically designed for cars, and is sensorless. When I'm racing mine on the local track you cannot tell its brushless, let alone sensorless when you watch it (I'm using a Feigao 380 9s so its similar in power to 12-13t mod motors on the track I run). I very often use cheap batt packs (sanyo 3300 cells) because I've converted all my good GP packs to 7 and 8 cells which I can't use for TC racing. I think this contradicts your statement somewhat CharlieS.

e_lm_70

09-07-2005, 11:52 AM

There are two different type of markets for RC car : one is for bashing and one is for racing.

I think there is more cash in the bashing market then in the racing market.
As well in the bashing market there is no limitation in the fantasy of the designer of motor/esc.

In the name of keep price down in the racing environment a 150$ motor (like C40 or Shadow) is consider too advanced and/or too expensive.
But even a club racing guy is forced to have a lathe (150$ minimum) and spend 5$ in brushes every few recing events.

At least Novak is trying to change something in a smart way ... but clearly Novak is not "no-profit" comany ... so why they should help on allow Hacker and Plentenberg motors in the ROAR-IFMAR ... if these company don't want even to spend time on comunicate with the race entities ?

e_lm_70

P.S: What I don't get ... what the hell: why a Hacker motor cost less in US then in Germany ? I had to get my C40 from Japan for get for a reasonable price ... as well ... while it would cost me less to order a U75 from US, then locally in Europe ...

kufman

09-07-2005, 12:33 PM

wow!!! can we see the whole race? I would like to say the sensorless system is the redish/orange car was quick on the start!

The brushless was #2 on the grid and it is Red with White stripes(I think yo may have been talking about #3 on the grid). The whole video is on the first page of this thread but I will repost it here too

http://kufman.com/img/Stuff/car_pics/AJs%202005%20Divx2.avi

It is about 20MB

P.S: What I don't get ... what the hell: why a Hacker motor cost less in US then in Germany ? I had to get my C40 from Japan for get for a reasonable price ... as well ... while it would cost me less to order a U75 from US, then locally in Europe ...

I don't understand this either. I ordered my u-force from Australia and I think I will get my c40 from aircraft-world.com which is also outside the US. Even paying the heafty shipping from Australia, my u-force was still cheaper than anywhere else.

CharlieS

09-07-2005, 01:04 PM

Okay, I take it back then. :)

BobNovak

09-07-2005, 09:13 PM

Thank Bob,

I did some research in the last day on internet, and it look like that there is a common agreement that wye and delta have the same top efficiency (assuming that both are build up at their best) . Strange stuff is that lehner motor seem to work better in delta mode. But this could be a lehner specif issue.

From what I can see, it is more easy to get high RPM per volt with the delta motor, and high rpm per volt is something nice for RC car (since the power control is more smooth).

Actually I don't see any technical reson for avoid delta motor in the IFMAR and ROAR.

e_lm_70

P.S: BTW Lehner motor are 2 pole motor (at least the 15xx, 19xx and Basic xx). Every motor, brushed or brushless (delta & wye) have better top efficiency with higher voltage.

P.S: It would be nice to allow in IFMAR & ROAR all generic motor brushed and brushless ... anyhow it is not the +/- 50$ of the cost of the motor that make any difference in the cost for partecipate to a race ! Keeping the limit to 6 NiMh/NiCd cell, this is already a limit on allow similar power among the competition !

Finally: The BL story in ROAR/IFMAR is an half empty glass story ... you can see in a positive way : thanks to Novak now it is possible to race also brushless in the car competitions ...or in a negative way: since Novak dictated the BL rules, then only specs friendly to Novak have been accepted (all the BL motor present in the market, a part from the Novak, have been defined as not legal !)
First off let me say I did not dictate the rules. We only made a motor that was as close to an existing ROAR/IFMAR brushed motor as posible hoping that it would be accepted more readily by these organizations. The rules for this motor were than approved by most of the existing brushed motor manufacturers in the R/C car industry. These rules were than made public to all and we ran a provisional brushless class in ROAR for one full year. During that year there was absolutely no input from any of the other existing Brushless Motor Manufactors and therefore they were accepted by both ROAR and IFMAR the next year. The only way that these rules or any rules can be changed in these organizations is by inputs from racers or to some degree manufacturers to change them. This is the democratic way and I have no problem with that. But remember that motors in these organizations are spec motors and are based on a one type of design that all have to follow.
Bob Novak

nicholcgn

09-08-2005, 08:07 AM

Bob,

I would not worry too much on defending yourself. Most of us understand that you took a chance with a product and have made it successful. The people who are mad are the ones that took a chance on another company and basically these companies do not give a dang about the car market overall. So now they are left out in the cold at this time. Do I hope the other companies put out some products soon? You bet. Then more people will see who has quality products and who does not. My bets are still on the companies that currently support the car market to come out on top.

Why people always want to criticize someone who assessed a tech and found a way to make it work and get accepted is beyond me. If Novak could make its own rules then I am sure you would have seen many other rules made in their favor.

kufman

09-08-2005, 08:16 AM

Why people always want to criticize someone who assessed a tech and found a way to make it work and get accepted is beyond me

I am mainly irritated because the ss5800 is no way lives up to the original specs. It was advertised as being faster and more powerful than a 10 turn where in reality it was closer to a 13 or 14 turn motor. Also, alomst all the other brushless companies have specs that correlate to eachother and novaks don't. I don't know who is correct, but novak and the rest of the world are very different. It isn't just because I only have 1 ss5800, I have had 3 and they are all the same. I enjoy using the ss5800 for what it is, but there was a huge dissappoinment when I first drove it.

schenck77

09-08-2005, 08:57 AM

kufman,
I totally get were you are coming from. before I bought the novak 5800 I had a lehner basic 4200 and 5300. I am sure you already know were I am going with this. The novak was slower then the 4200 even if you geared them the same. Comparing the novak to the 5300 wasn't even close.

masterdummy

09-08-2005, 10:23 AM

well I heard someone in an interview saying that the ss5800 was never intended to be raced... :confused:

anyway novak makes great products I have always bought controllers and chargers from them my novak dually has been performing flawlessly since they last replaced it for free in year 2000 and it was my fault, never had any issues with my 410m-5, XXL and not either my millennium pro charger... this time i didn't go with the ss5800 because all the thermal issues and signs of a weak motor I read about instead went for a schulze/lehner very strong combo but I won't reject the idea of getting one of the newer generation systems like the 5.5 and 6.5 from novak.