Finalized! - Longboard Alien Drive Systems - single C6374

[made_in_the_alps_legacy]

thxs for your feedback - well yep, there is a whole world to be discovered if we start to reduce our "reliability factors" to become lighter... maybe 4S / 80A would please most of us for flat tarmac ride applications... it's not that clear what you mean by peak power... at least from the esc specs point of view : 150A is continuous allowable current...
( I agree about not taking too seriously the motor rated power, maybe it overheats at this load... and I am fine with "overdesigned" builts : they "have to be" reliable -

can we really say "overpowered" since we don't reach the rated power of any of the components but only a 1/4 of it ? )

 

[666yeti666]

Overpowered indeed yes, however it's nice to drive away on the board without having to push it firstly.
I'm curious to its climbing abilities when I drive it on a bridge too the office.

Anyway, yesterday I’ve checked the settings of the hobbywing Ezrun 150A and they are as follows (of which not all are important for the matter):

1: forward&brake
2: drag brake 0%
3: voltage protection 3.2V/cell
4: “DRRS” punch , level 1 => this is the amount of punch when driving off and can be programmed until level 9. So I’ve programmed the lowest punch, which is fine for driving off easily
5: brake force : 50% => speaks for itselves and I think it should be increased. Now I have programmed it to 75%
6: reverse force 25%
7: initial brake 0% => It is also called “minimum brake force”, and it refers to the force when the throttle stick is located at the initial position of the backward zone. The default value is equal to the drag brake force, so the brake effect can be very smoothly => programmed to 0% but maybe has to be changed ???
8: neutral range 9%
9: “AMTS” timing 5 => this equals 15degrees (default value) and can be changed from 0 to 26.25 degrees in 3.75degree steps
10: not present (?)
11: motor rotation CCW
12: lipo cells 6 cells / 22.2V

So for the brake sound I will experiment with the motor timing, however this also influences speed and heat in the ESC as well, which is of more importance then the sound of course
For brake behavior I can change 5 and 7.

Anybody already experimented with above settings ?

Thanks
Regards
Sebastien

 

[made_in_the_alps_legacy]

see the following topic...
http://endless-sphere.com/forums/viewtopic.php?f=35&t=57068
...where your ESC settings could be adressed.

 

[666yeti666]

Ok, thx will do so.

Below some nice datalogger graphs of two sessions in the (very crowded !) park.

Explanation of the graph :
Horizontal axis is time in minutes

Left vertical axis :
Power [W] , orange line
(Cumulative) current consumption [mAh] , blue line

Right vertical axis :
Current [A], brown line
Batteryvoltage [V], dark blue line


Session 13 is of riding 3 rounds in the park of about 1.2km each. The second part of each round contains some kind of hill which is recognized by the power increase in the second half.

Nice to see is that the average current draw is very very low, with peaks untill about 26A
The power has peaks until 650W which is true of course since the batteryvoltage equals about 25V.
The battery is holding up great, which is seen by the nice flat curve. Even at high power peaks it almost does not drop.

(the peak at 12minutes must be some failure measurement since it’s going infinite…)

Roughly it can be said that under the applicable conditions of that session (flat smooth road), the current consumption for 1.2km is only about 500mAh (during about 9 minutes).
With an average batteryvoltage of 25V, this would lead an energy consumption of about 83W/hour.

I wonder how the power increases when climbing the bridge to my office …
To be continued…
Regards
Sebastien

session 13:


session 14:

 

[torqueboards]

I was originally using 10S on 6374-192kv motors and it was overpowered. I would barely ever use full throttle and use it at max speed. I been using the same dual motors 6374 on 6S and it works just as fine. I'm switching out my 63mm motors for 5055-280KV SK3 motors as the 63mm motors are meant for a higher voltage system. However, 10S is very fun just not practical for a commute. I want a much lighter board. I climb tons of hills uphill and downhill on a daily basis. I'll repurpose my dual 6374 w/ a 12S setup for fun.

It's probably most easiest when switching to just change the gearing ratio from about 1:2 to around 1:3.

My ideal board is going (2) 5055-280KV SK3 motors on 6S. I'm just waiting on my mounts. It will be much lighter than the 6374 motors (they are heavy). Should be very light.

 

[Murfix]

Nice data!

What did you use to log it?

 

[made_in_the_alps_legacy]

My ideal board is going (2) 5055-280KV SK3 motors on 6S. I'm just waiting on my mounts. It will be much lighter than the 6374 motors (they are heavy). Should be very light.

common' go 42mm diameter motor, someone has to try (just kidding )

 

[666yeti666]

Nice data!

What did you use to log it?

http://www.eagletreesystems.com/index.php?route=product/product&product_id=54

Only I am using previous v3 version which I had on the shelf.

 

[Cyberiarvo]

Hi guys, i just want to know if the SK3-6354-260kv motor which is rated 8-10s lipo can run on 6s?

Im a bit worry because i will be using Hk150 esc which is 2-6s lipo only.

Pls help.

 

[torqueboards]

Hi guys, i just want to know if the SK3-6354-260kv motor which is rated 8-10s lipo can run on 6s?

Im a bit worry because i will be using Hk150 esc which is 2-6s lipo only.

Pls help.

Yes, the motor will be fine using with 6S.

 

[Cyberiarvo]

Thnks TB for your reply.

My setup:

Sk3 6354 260kv single drive, HK 150 esc, pulley 36T and 14T, using 5a 6s lipo.

Will i have enough torque on uphill with this setup? Any comment or suggestion?

This is my first build and im hoping for your help.

 

[torqueboards]

Thnks TB for your reply.

My setup:

Sk3 6354 260kv single drive, HK 150 esc, pulley 36T and 14T, using 5a 6s lipo.

Will i have enough torque on uphill with this setup? Any comment or suggestion?

This is my first build and im hoping for your help.

Yes, you should be fine. Dual motors is better but single is fine as well. I would suggest making your own thread rather than hijacking this thread.

 

[Cyberiarvo]

Thnks tb, lol sory for the hijack.

 

[666yeti666]

So for the brake sound I will experiment with the motor timing, however this also influences speed and heat in the ESC as well, which is of more importance then the sound of course
For brake behavior I can change 5 and 7.

Thanks
Regards
Sebastien

Now that I have thought about it; the timing will not influence the PWM frequency of course and as such it will not change the braking sound.
The manual states it has "ABS braking" which means "pulsed braking" and most probably this pulsing is causing the braking sound...

Sebastien

 

[666yeti666]

Hi guys,
well I have to admit I’m as happy as a child can be Today I drove to my work and back and everything went well !
The board drives really good and stable. It has lots of torque and it climbed the bridge without any troubles , I even could accelerate significantly.
Total distance was 8km and I used 3000mAh in total (so 20% left in the 6s 5000mAh package). When I arrived back in my street, just in front of my garden, the low voltage alarm went off and I can tell you, that makes lots of noise.

I made a log of course as well as GPS tracking. On the long ends the speed was between 16 to 19km/h , with a total average of about 15km/h, and for me that’s a nice and SAFE speed. Maybe in future when I get more aquainted with the board the speed will increase but for now this is satisfying to me.

Below you can see the pictures of the left over capacity and what went in again.

I had changed the brak setting to 75% which gives much better braking, even driving down the bridge.

So I can say that this project is successfull ! Now let’s see how well the mechanics hold up after time. I will not drive this thing in the rain since that’s asking for troubles...
I will post some updates in the future

to be continued ....

Sebastien

Datalog file :

 

[torqueboards]

Awesome yeti. I'm sure, you'll enjoy it. These eboards are a blast of fun. You should be reaching higher miles with a 5000mah pack. I use (2) 3S 5000mah packs in series for 6S and I usually get about 6-8 miles with my terrain and riding style. This is also with dual motors. I assume with more conseritive speeds you can reach 12-15 miles for a 5000mah pack. I have over 900 miles or so on my eboard now and it's a blast every time. Have fun!

 

[made_in_the_alps_legacy]

what power reading did you get along this hill ? I see one spike at 2.7kW is that correct ? or is it MAX 539.52 W ?

 

[666yeti666]

@ torqueboards,
thx!
Well higher milage on a 5000mAh pack .... maybe possible, but I prefer too leave about 15-20% of capacity in the package for better life-time of the package (don't ask me how I know ...).
Maybe I will switch over to 8000mAh packs to get a little more 'headroom' , but for now let's see how it works.

@ alps_legacy,
the power curve is in orange, so the maximum power peak equals indeed 539W.
The other peak is for the maximum current ; 24.7 A
(the right y-axis is for power and current consumption, the left for current and batteryvoltage)

The peak was not from riding the bridge, that is somewhere in the first part of the graph, so between 2 and 16 minutes. And I think it is starting at the 6th minute. At the 8th minute I crossed the bridge and walked down the stairs at the other side.
At 11.5 minutes I stopped and checked the current consumption.
At the 16th minute I arrived at the gate of my work, checked the current consumption again, resetted the GPS and drove back.

The high current peaks are from driving off from a dead stop (eg. waiting at the traffic lights) and I can recognize I'm getting more brave when driving off :lol:

regards
Sebastien

 

[torqueboards]

6-8 miles is with my pack at 3.5-3.7v left on each cell.

 

[666yeti666]

6-8 miles is with my pack at 3.5-3.7v left on each cell.

mmmm .... well ...when did you measure that voltage ? When you wait some time, the voltage will recover a little, so for me, my reference is the amount of current that will go into the battery again. In my case, that was about 3000mAh. I think the volage is a less accurate reading.

 

[torqueboards]

6-8 miles is with my pack at 3.5-3.7v left on each cell.

mmmm .... well ...when did you measure that voltage ? When you wait some time, the voltage will recover a little, so for me, my reference is the amount of current that will go into the battery again. In my case, that was about 3000mAh. I think the volage is a less accurate reading.

Sometimes both. If at 3.5v it might end up being 3.7 afterwards maybe few hours later I would check. What are you using to calculate the mah left? On a side note - How fast are you charging your batteries?

 

[Cyberiarvo]

Hi yeti,

Seems like we have the same track and wheels size, can you tell me the distance or gap of your motor to the deck? Did you put some plate to make your trucks extended?

 

[666yeti666]

6-8 miles is with my pack at 3.5-3.7v left on each cell.

mmmm .... well ...when did you measure that voltage ? When you wait some time, the voltage will recover a little, so for me, my reference is the amount of current that will go into the battery again. In my case, that was about 3000mAh. I think the volage is a less accurate reading.

Sometimes both. If at 3.5v it might end up being 3.7 afterwards maybe few hours later I would check. What are you using to calculate the mah left? On a side note - How fast are you charging your batteries?

Well, with my on-board datalogger I can read out the consumed current, so I can estimate what's left in ( although a lipo battery rarely can deliver 100% what is mentioned on the label...)

@Cyberiarvo:
there's 15mm left between the motor and the deck, see pictures. I'm using 10mm risers between the deck and the truckbase, otherwise I would get wheelbite and launched off the board during sharp turns.

 

[Cyberiarvo]

Thnks Yeti!

 

[666yeti666]

On a side note - How fast are you charging your batteries?

Usually charging with 2C, so that means for my 5000mAh package, with 10A (1C = 1 time the capacity, 2C = 2 times the capacity etc.).
However this cannot be done with all lipo batteries. It must be mentioned on the lipo.
But usually the ones with higher C ratings (> 30C) are suitable. This has to do with the internal resistance which must be low to prevent battery overheat issues. The higher the C rating, the lower the internal resistance will be.

Sebastien