Preview of version 2 of the hub motor / ebike simulator

[rwright]

Welcome to the forum rwright. To simulate the addition of 100w of leg power, just click on the load line at the point where it would intersect 100w higher.

If I understand correctly, I manually move the cursor up in speed from the default load/power intersect and the difference between "Mtr Power" and "Load" is the power supplied by the legs. And the rest of the results, most importantly for me "range", are updated correctly. (Note: Acceleration is incorrect, but that's to be expected.)

I still need to repeatedly move the cursor as I iterate the throttle until I reach the desired conditions, but that's still a lot easier than faking the aerodynamics.

Thanks for the good suggestion psycholist.

 

[justin_le]

Welcome to the forum rwright. To simulate the addition of 100w of leg power, just click on the load line at the point where it would intersect 100w higher.

If I understand correctly, I manually move the cursor up in speed from the default load/power intersect and the difference between "Mtr Power" and "Load" is the power supplied by the legs. And the rest of the results, most importantly for me "range", are updated correctly. (Note: Acceleration is incorrect, but that's to be expected.)

That is correct. Everything in the stats would be correct except for the 'accelleration' value, which should be zero but will instead show the deceleration you would get if you stopped pedaling.

I still need to repeatedly move the cursor as I iterate the throttle until I reach the desired conditions, but that's still a lot easier than faking the aerodynamics.

We'll be modifying the simulator soon enough to simplify the process of getting these numbers. The plan at the moment to have two new fields, one for human power level, and a checkbox to select "auto adjust throttle".

If "auto adjust throttle" is selected, then as you move the cursor left and right to different speeds, the simulator will automatically find the right throttle point which results in the motor +human power curve crossing the load curve exactly at the cursor position. It will run a bit slower because the code will have to iteratively hone in on the right throttle value, but it will still be a lot faster than doing these adjustments manually!

-Justin



Thanks for the good suggestion psycholist.[/quote]

 

[andreym]

We'll be modifying the simulator soon enough to simplify the process of getting these numbers. The plan at the moment to have two new fields, one for human power level, and a checkbox to select "auto adjust throttle".

the phase current limit field would be also VERY useful in a new version

 

[rwright]

We'll be modifying the simulator soon enough to simplify the process of getting these numbers. The plan at the moment to have two new fields, one for human power level, and a checkbox to select "auto adjust throttle".

If "auto adjust throttle" is selected, then as you move the cursor left and right to different speeds, the simulator will automatically find the right throttle point which results in the motor +human power curve crossing the load curve exactly at the cursor position. It will run a bit slower because the code will have to iteratively hone in on the right throttle value, but it will still be a lot faster than doing these adjustments manually!

-Justin

That sounds like it should work well. And the auto adjust throttle will be useful even without human power.

 

[miuan]

One more thing to update.. the vehicle weight is a crucial thing on steep hills, it would sure be essential to enable a similar setting as throttle, i.e. set up a default value of 100kg, but enable any integer number from 50 to say 400kg.
I struggle to get usable plots for my 125kg bike+rider setup.

 

[justin_le]

One more thing to update.. the vehicle weight is a crucial thing on steep hills, it would sure be essential to enable a similar setting as throttle, i.e. set up a default value of 100kg, but enable any integer number from 50 to say 400kg.
I struggle to get usable plots for my 125kg bike+rider setup.

At the bottom of the vehicle weight dropdown table is an option for "custom weight", which lets you type in any value in kg or lb without restriction. You can even put in a negative weight to simulate riding with a blimp strapped to your back.


Is this not working for you? -Justin

 

[miuan]

Is this not working for you? -Justin

Sorry, I just completely missed that option! Great!

 

[rwright]

Hi Justin, any update or further thoughts on adding the human power and auto throttle?

Welcome to the forum rwright. To simulate the addition of 100w of leg power, just click on the load line at the point where it would intersect 100w higher.

If I understand correctly, I manually move the cursor up in speed from the default load/power intersect and the difference between "Mtr Power" and "Load" is the power supplied by the legs. And the rest of the results, most importantly for me "range", are updated correctly. (Note: Acceleration is incorrect, but that's to be expected.)

That is correct. Everything in the stats would be correct except for the 'accelleration' value, which should be zero but will instead show the deceleration you would get if you stopped pedaling.

I still need to repeatedly move the cursor as I iterate the throttle until I reach the desired conditions, but that's still a lot easier than faking the aerodynamics.

We'll be modifying the simulator soon enough to simplify the process of getting these numbers. The plan at the moment to have two new fields, one for human power level, and a checkbox to select "auto adjust throttle".

If "auto adjust throttle" is selected, then as you move the cursor left and right to different speeds, the simulator will automatically find the right throttle point which results in the motor +human power curve crossing the load curve exactly at the cursor position. It will run a bit slower because the code will have to iteratively hone in on the right throttle value, but it will still be a lot faster than doing these adjustments manually!

-Justin

Thanks for the good suggestion psycholist.

[/quote]

 

[justin_le]

Hi Justin, any update or further thoughts on adding the human power and auto throttle?

Not yet I'm afraid, but we have two new people with software/programming backgrounds who will be starting work in April and the plan is to have one of them focus predominantly on upgrades and enhancements to our web apps, and the good 'ol simulator is the most overdue so would get first priority.

 

[chas58]

I use that thing all the time, it is wonderful.

It could use the popular Q100H model - as a lot of people here use it. However, the 328rpm motor can (to some degree) estimate the lower RPM motors by changing the wheel type.

To simulate a 201rpm motor on a 700c/26” wheel, enter a 16” wheel size
To simulate a 260rpm motor on a 700c/26” wheel, enter a 20” wheel size

 

[MadRhino]

To simulate a 201rpm motor on a 700c/26” wheel, enter a 16” wheel size
To simulate a 260rpm motor on a 700c/26” wheel, enter a 20” wheel size

That trick will produce false results, in heat and torque especially.

 

[justin_le]

To simulate a 201rpm motor on a 700c/26” wheel, enter a 16” wheel size
To simulate a 260rpm motor on a 700c/26” wheel, enter a 20” wheel size

That trick will produce false results, in heat and torque especially.

Correct, that is NOT how you would simulate different rpm/V windings. To simulate a different winding type reasonably accurately, you should change your battery voltage and battery current limit in proportion, not the wheel size which should stay the same.

So for instance, if you have the 200 rpm motor and you want to see the behavior with 48V battery pack with a 15A motor controller, you can choose the 328 rpm winding that is on the simulator, but then set your battery voltage to 29.3V (48*200/328) and set the controller current limit to 24.6A (15 * 328/200). THAT would then show quite accurately the output performance of the 200 rpm motor 48V 15A setup.

A 200 rpm 48V 15A system will behaved identically to a 328 rpm 29V 24A setup.

It could use the popular Q100H model -

Anyone is free to donate a motor to have it fully dyno characterized, modeled, and put up on the simulator page. That's how the MXUS motors (TeslaNV), the MAC motors (Damon directly), the Cromotor (Sterling from Bend Electric Bikes), the Leaf, BMC, and several others got on the list.

 

[chas58]

To simulate a 201rpm motor on a 700c/26” wheel, enter a 16” wheel size
To simulate a 260rpm motor on a 700c/26” wheel, enter a 20” wheel size

That trick will produce false results, in heat and torque especially.

Correct, that is NOT how you would simulate different rpm/V windings. To simulate a different winding type reasonably accurately, you should change your battery voltage and battery current limit in proportion, not the wheel size which should stay the same.

So for instance, if you have the 200 rpm motor and you want to see the behavior with 48V battery pack with a 15A motor controller, you can choose the 328 rpm winding that is on the simulator, but then set your battery voltage to 29.3V (48*200/328) and set the controller current limit to 24.6A (15 * 328/200). THAT would then show quite accurately the output performance of the 200 rpm motor 48V 15A setup.

A 200 rpm 48V 15A system will behaved identically to a 328 rpm 29V 24A setup.

Good to know, thanks!!!

That does yield different curves

I must be doing something wrong.
My 200rpm Q100 has a road speed of ~15-16mph, and a noload speed of 18mph.
using the 16" wheel on a 328rpm Q100 matches these numbers.
Using the formula, it doesn't seem to match

With battery = 36*200/328= 21.9
Current = 15*328/200 = 24.6

it shows the road speed of 13.4 and a noload speed of 17mph. A little low (although close)

Or running at 48v, the road speed is ~20mph and noloads speed of ~24mph.
using a 20" wheel is pretty close to these speeds.
USing 48*200/328 = 29.26
Current = 15*328/200 = 24.6
gives a road speed of 17.4 and a noload speed of 22.5. Seems a little slow...

Maybe my measurements are slightly off...

 

[justin_le]

That does yield different curves

It's quite possible that it's not the same hub unfortunately, the 328rpm cute motor that I dyno characterized a few years ago had an effective pole pairs of 65, while the latest one that a customer brought into our store was closer to 114, so a much higher internal gear reduction, not the same motor with a different winding even though both were called Q100s.

In any case, the technique of changing the voltage AND current in by the ratio that you want to change the KV's as I described IS the correct way to simulate a setup with a different winding speed. If you found that the results were a little lower than your measured unloaded, then simply increase the voltage (and correspondingly decrease the battery amperage ) until they do match. This will be much more correct in terms of the predicted thrust and efficiency than changing the wheel size.

-Justin

 

[chas58]

Thanks justin. I agree.

Obviously the speed is controlled by the voltage, so the math is spot on. I can tweak it from there to get my measured speeds as you indicated. Good feedback!

 

[ScooterMan101]

Simulator First ?

I put in a Request for the Software Programmers to , First work on Web Videos on how to adjust the C.A. V 2.3 and C.A. V 3.0-3.1

Example on My C.A. V 2.3 that I bought from you I gave you the Ohm of my controller , 1.10 M Ohm , So it came adjusted for that controller.
However
I now have a new controller that I want to use that is , 1.98 M Ohm

I have read twice through the Manual for the V2.3 and find no instructions on how to change the C.A. to work with the new controller .
The advanced section of the Manual is even very confusing to me, With a Video , Step by Step, done slow enough to show each press or series of presses on the buttons would be they way I could learn any of the Advanced Settings .

A video on How to Change what ever needs to be changed on the C.A. to work with a different controllers is , I am sure needed .
Can it be done with the Buttons on the Face of the C.A. ? Does it need a Cable ? Done with Chrome O.S. ?
Many people are now using Android , and Chrome .

Hi Justin, any update or further thoughts on adding the human power and auto throttle?

Not yet I'm afraid, but we have two new people with software/programming backgrounds who will be starting work in April and the plan is to have one of them focus predominantly on upgrades and enhancements to our web apps, and the good 'ol simulator is the most overdue so would get first priority.