Anomalies Present in Enertion Video / Data Logging Software?

[devin]

I watched a data logging video recently which was produced by electric skateboard company Enertion, and in the video I noticed some strange numbers in the logging data which in my opinion appear to be possible anomalies or errors in the logged data.

I am at a loss to explain how these numbers could have been possibly been produced in the data log of the Enertion video.

This belief is based on a comparison of the Enertion-produced video with another logging video produced by Benjamin Vedder, inventor of the VESC Brushless Motor Controller, as well as my understanding of VESC pulsed power physics (described in detail at website MotorAmps.com ).

As evidence for the anomalies, in the Benjamin Vedder video, a simple ratio exists at all times to a high degree of accuracy between "Battery Current," "Motor Current," & "Duty Cycle."

The ratio between these numbers is completely described by the formula:

motor amps x (duty cycle / 100) = battery amps

In the Enertion-produced video however, the numbers vary from this formula by a wide margin, indicating to me possible faults or bugs in the logging software?

Anyone have an opinion?

This topic was originally posted at: http://buildelectricboards.com/showthread.php?tid=165

Benjamin Vedder produced video:
https://youtu.be/nGb-zt2Jp9k

Enertion produced video:
https://youtu.be/Pfu2BoXPB7Q

 

[devin]

I analyzed a random frame from a random VESC logging video from youtube ( https://youtu.be/R8FO4BkfFZ4 ), and looked at these numbers described by the formula:

motor amps x (duty cycle / 100) = battery amps

In the Enertion-produced video, the numbers vary from this formula by a wide margin (10.36 Amps).

In this random video, the variation is much smaller (0.04 Amps) -- smaller even than the difference in the Benjamin Vedder video.

Random VESC Logging Video #1:
https://youtu.be/R8FO4BkfFZ4

Benjamin Vedder produced video:
https://youtu.be/nGb-zt2Jp9k

Enertion produced video:
https://youtu.be/Pfu2BoXPB7Q

I analyzed another random frame from a random VESC logging video from youtube ( https://youtu.be/bxSrCjUnLUc ), and looked at these numbers described by the formula:

motor amps x (duty cycle / 100) = battery amps

In the Enertion-produced video, the numbers vary from this formula by a wide margin (10.36 Amps).

In this random video, the variation is much smaller (0.07 Amps) -- smaller even than the difference in the Benjamin Vedder video.

Random VESC Logging Video #2:
https://youtu.be/bxSrCjUnLUc

Benjamin Vedder produced video:
https://youtu.be/nGb-zt2Jp9k

Enertion produced video:
https://youtu.be/Pfu2BoXPB7Q

I analyzed another random frame from a random VESC logging video from youtube ( https://youtu.be/eaLUqa4avyA ), and looked at these numbers described by the formula:

motor amps x (duty cycle / 100) = battery amps

In the Enertion-produced video, the numbers vary from this formula by a wide margin (10.36 Amps).

In this random video, the variation is much smaller (0.01 Amps) -- smaller even than the difference in the Benjamin Vedder video.

Random VESC Logging Video #3:
https://youtu.be/eaLUqa4avyA

Benjamin Vedder produced video:
https://youtu.be/nGb-zt2Jp9k

Enertion produced video:
https://youtu.be/Pfu2BoXPB7Q

I analyzed another random frame from a random VESC logging video from youtube ( https://youtu.be/VYFn2Pcjlng ), and looked at these numbers described by the formula:

motor amps x (duty cycle / 100) = battery amps

In the Enertion-produced video, the numbers vary from this formula by a wide margin (10.36 Amps).

In this random video, the variation is much smaller (0.01 Amps) -- smaller even than the difference in the Benjamin Vedder video.

Random VESC Logging Video #4:
https://youtu.be/VYFn2Pcjlng

Benjamin Vedder produced video:
https://youtu.be/nGb-zt2Jp9k

Enertion produced video:
https://youtu.be/Pfu2BoXPB7Q

I analyzed another random frame from a random VESC logging video from youtube ( https://youtu.be/gPOxwxR8cfk ), and looked at these numbers described by the formula:

motor amps x (duty cycle / 100) = battery amps

In the Enertion-produced video, the numbers vary from this formula by a wide margin (10.36 Amps).

In this random video, the variation is much smaller (0.01 Amps) -- smaller even than the difference in the Benjamin Vedder video.

Random VESC Logging Video #5:
https://youtu.be/gPOxwxR8cfk

Benjamin Vedder produced video:
https://youtu.be/nGb-zt2Jp9k

Enertion produced video:
https://youtu.be/Pfu2BoXPB7Q

 

[Ackmaniac]

That's unacceptable. Somebody should call the cops.
Or we found a new source of free energy.
Little hint, check what happens when a float get's converted to a int.

 

[flat tire]

He asked a legit question, I would be curious about the discrepancy too. Not everyone writes code or even knows what a float is.

 

[devin]

That's unacceptable. Somebody should call the cops.
Or we found a new source of free energy.
Little hint, check what happens when a float get's converted to a int.

He asked a legit question, I would be curious about the discrepancy too. Not everyone writes code or even knows what a float is.

@Ackmaniac

how would someone go about proving that the test data in the Enertion promo video wasn't deliberately falsified or modified?

after all, their marketing slogan claims their boards to possess the "Most Powerful Direct Drive."

surely there is a way to independently verify the claim.

if someone else logged data from an Enertion board, would it also not follow the motor amps x (duty cycle / 100) = battery amps formula -- or does it only not follow the formula when the testing is performed by Enertion?

 

[Ackmaniac]

Has nothing to do with Enertion.
When a float is converted to a int then it rounds it down.
Means 8,6542% duty cycle get's converted to 8%.
In Vedders video (BLDC) the duty cycle has a precision of 1 number after the comma.
In the Raptor 1 Video my app only shows a precision of full %.
So if you see 8% then you could also calculate it with 8,99% and if the data is then in between it is correct.

The Raptor 2 video runs in FOC. And in FOC the duty cycle which is shown by the VESC firmware is not correct. In the firmware the duty cycle get's divided by 2/3 * ∛2 which is (0.86602540378).
In reality the duty cycle is then when you see 95% at 82.27% because you apply current to all 3 phases.
When you take that into account then you get much closer to the real value. And be ware of the float int issue.

BTW i am the developer of this app that is shown in the video.
@ Flat tire: sadly there is never a legit answer to any of devins questions. At least not for him.