Cycle Analyst V3 preview and first beta release

[Stealth_Rider]

Hi Teklektik,
I appreciate the new manual especially the addition of the detailed tuning procedure in the section "Speed Adjustment for Higher Powered Bikes" on page 46 of the manual.

I have installed the CA V3 (Ver3 Prlm 5 on both bikes) on two Stealth bikes that I own: the Bomber and the Fighter. Here's a picture gallery for the bikes:
1. Fighter: http://www.fareinc.com/65/CAV3_install/index.html
2. Bomber: http://www.fareinc.com/65/CAV3/index.html

I'm trying to tune the CA V3 on my Fighter and I was following the procedure from the manual:

"3.Increase PSGain to the point where a single modest overshoot occurs before the speed settles.If no setting produces overshoot, this procedure is not appropriate - instead use the procedure for lower powered bikes. Note: The low power procedure is presently under development."

I raised PSGain to its highest value, 9.99, and I was unable to obtain an overshoot. I'd like to experiment with the under development procedure for lower powered bikes and would appreciate a recommendation of where to start on this so I can try it and provide some feedback.

Can you help?

-Jim

 

[teklektik]

I raised PSGain to its highest value, 9.99, and I was unable to obtain an overshoot. I'd like to experiment with the under development procedure for lower powered bikes and would appreciate a recommendation of where to start on this so I can try it and provide some feedback.

Can you help?

Unfortunately, not too much. I was working this a few months ago and got interrupted so things are not in a good state of affairs at this end . I was doing the development on my bike running a single motor and was getting just so-so results - I think in part because the bike is so heavy. It was pretty easy to get workable settings, but the procedures I tried led to different settings depending on the phase of the moon. I was still looking for easily identified unambiguous characteristics (overshoot, undershoot, oscillation, ratty power (rapid oscillation)) to guide the process - only marginally successful. Oddly, the high powered procedure was much easier to work out.

That said - I believe that you will find that the error term (IntSGain) is going to play the biggest role for low to moderate power bikes. I really hate to make any recommendation without testing it first, but you might try setting PSGain around 4 or 5 and then move on to step 5. If you have difficulty getting the overshoot under control, you can try increasing PSGain by 1.0 at a time and then re-starting with step 5 again. I was testing strategies similar to this and was able to bring the bike to any number of workable 'tunes' - some with more overshoot than others, etc. It wasn't hard to get the bike tuned, just hard to specify a procedure that would give the same tune twice....

Frankly, control theory is not my area of working expertise and tuning PID controllers is an art form (I'm at the 'crayons' level ). Anyhow, hope this helps a bit...

 

[izeman]

i installed my pas and i works nice. set it to autopas and i works. it kicks in really fast and accurate. but i'd like to stop it INSTANTLY if i stop pedaling. that's why i also set "ThrO -> Down Ramp" to 0.05s/V as i want the motor to stop immediately if there is no input.

as i can not adjust pas power level (yet) i set it to 700w, which i good enough to climb little hills, but almost to much for low speed cruising.

so i wanted to test "Torq PAS". as i understood this uses PAS input to set watts related to rpm > 55 relatively. so at 55rpm it kicks in and raises watts the faster you pedal. correct?

i set the following parameters:

PAS -> PAS Mode - Torq PAS
PAS -> MxThrotSpd - 99km/h (don't know if this is relevant)
Trq -> Trq Sensr Type - Custom
Trq -> Trq Scale - -200 Nm/V
Trq -> Trq Offst - 0V (reset while shorting pin2+5)
Trq -> Asst Factr - 1
Trq -> Asst Start - 0 Watts

but there is no power added, no matter how fast i pedal.

EDIT: just found it: you have to adjust "Trq -> Trq Scale" to 25 to get 700W output. don't know how i could overread that. it's such a big spreadsheet

maybe a little request:
could the values "PAS -> PAS Watts" and "Trq -> Trq Scale" be saved per preset as well, and not globally? it would make sense to have lower power/rpm on a "legal" setting, and higher on a "fun/offroad" setting.

 

[teklektik]

as i understood this uses PAS input to set watts related to rpm > 55 relatively. so at 55rpm it kicks in and raises watts the faster you pedal. correct?
EDIT: just found it: you have to adjust "Trq -> Trq Scale" to 25 to get 700W output. don't know how i could overread that. it's such a big spreadsheet

Not quite - it kicks in according to PAS->StrtThrsh and stops according to PAS->StopThrsh. The assist is the same up to 55rpm, then begins scaling proportionately with rpm.

Sounds like you have this figured out - hope it works well for you. I am liking the AutoTorqPAS setup a lot and find myself using PAS more and more. Quite a different riding experience - much more natural and bicycle-like .

maybe a little request:
could the values "PAS -> PAS Watts" and "Trq -> Trq Scale" be saved per preset as well, and not globally? it would make sense to have lower power/rpm on a "legal" setting, and higher on a "fun/offroad" setting.

That's an interesting point - we'll have to see where Justin goes with the idea, but it does seem to make sense.

It sounds like you are thinking about making PAS adjustable. As an alternative to the global variable change, there are a couple of ways to go to get a PAS assist knob limited in 'legal mode' with a little tinkering. For instance, the diagram below shows a preset switch (from the Guide section 6.3) with one legal preset and two unlimited presets. R1 and R2 are 4.7K resistors and do the preset selection. We use a DPDT toggle switch with center off (legal mode). The PAS adjust is based on the technique described in section 7.5. The second switch wiper enables the limiting trimpot R3 (5K) so that the external PAS adjust knob R4 (2K linear pot) can adjust over 0-100% (Offroad and Unlimited) or anywhere from 0-30% to 0-100% (legal mode) depending on the R3 adjustment.

Here you would select a TrqScale that gave you the max Offroad wattage you desire, then go to the legal preset and dial down R3 until the max PAS assist is legally compliant (a one-time setting). You would need to mount the preset switch and PAS knob someplace convenient. Other similar arrangements might be more to your liking, but you get the idea....

 

[izeman]

as i understood this uses PAS input to set watts related to rpm > 55 relatively. so at 55rpm it kicks in and raises watts the faster you pedal. correct?
EDIT: just found it: you have to adjust "Trq -> Trq Scale" to 25 to get 700W output. don't know how i could overread that. it's such a big spreadsheet

Not quite - it kicks in according to PAS->StrtThrsh and stops according to PAS->StopThrsh. The assist is the same up to 55rpm, then begins scaling proportionately with rpm.

yes. sure. it starts immediately, and at 55rpm starts to raise. that's what i wanted to say
thanks for explaining the different methods to control it. i still want to install a 3 way switch, so this is maybe what i'll use it for.
but the one question remains unanswered: can i tell the motor to stop immediately if i stop pedalling? i don't like it to still engage even though i don't pedal anymore, this feels REALLY unnatural.

 

[izeman]

one more thing to mention: pas-torque works GREAT. just as i was always wanted that feature to be. pedal slow and you get a little support, pedal fast and you fly
what did not work to my satisfaction was the almost instant full power. even 500w kicking in can be way too much when maneuvering. then i rethought it, and set "ThrO -> Up Ramp" back to 2s/V. now it's super smooth. but of course this makes the thumb throttle super laggy as well. maybe those two could be adjustable seperately?
i know i ask for much, and this makes setup even more complicated, but i think it's more convenient to have throttle ramp up/down be different for pas and thumb/twist throttle.
btw: setup right know is REALLY complex. and i LOVE it. it's a real geek gadget if you want it that to be

 

[teklektik]

it kicks in really fast and accurate. but i'd like to stop it INSTANTLY if i stop pedaling.

one more thing to mention: pas-torque works GREAT. just as i was always wanted that feature to be. pedal slow and you get a little support, pedal fast and you fly
what did not work to my satisfaction was the almost instant full power. even 500w kicking in can be way too much when maneuvering. then i rethought it, and set "ThrO -> Up Ramp" back to 2s/V. now it's super smooth. but of course this makes the thumb throttle super laggy as well. maybe those two could be adjustable seperately?
i know i ask for much, and this makes setup even more complicated, but i think it's more convenient to have throttle ramp up/down be different for pas and thumb/twist throttle.
btw: setup right know is REALLY complex. and i LOVE it. it's a real geek gadget if you want it that to be

First - thanks for the feedback - very useful!

As far as the immediate PAS cut-off is concerned, you can try increasing the StopThrsh setting. I had much the same issue and am running with (start,stop) = (5,20) with a 16 magnet wheel. But - I am not running Prelim5, so I'm not sure what such a wide value spread would do on the newest firmware. Something to try, though....

Unfortunately, UpRamp is applied quite late in the processing as Throttle OUT goes out the door. It applies to everything and the particular identity of the cause of the voltage changes is lost by then - making PAS-specific ramping not a really easy addition. This isn't to say some magic couldn't be worked with an all-nighter or two from Justin, but...

A few folks have reported the issue with sudden full power application. UpRamp is one way to address it, WGain is another. I was originally thinking about having some of these settings preset-specific, but I don't think that addresses all the problem scenarios and it sort of uses the presets as a crutch to get different behavior for PAS vs throttle operation. I think that a PASWGain setting may be a workable solution and not too hard to implement. This would separate the PAS and throttle terms and give each their own gain coefficient. PAS could be set with a low gain for slower power application and the throttle could be set higher for snappy response (in the same preset).

Yep - there sure are a lot of options - but Justin has arranged things so that the features are pretty compartmentalized and distinct - it's not a patchwork of overlapping functionality and trick settings. It's big but it all makes sense. Quite an accomplishment...

 

[teklektik]

even 500w kicking in can be way too much when maneuvering.

thanks for explaining the different methods to control it. i still want to install a 3 way switch, so this is maybe what i'll use it for.

I understand completely - I use a 3-pos switch myself. No wanting to flog this to death, but if you don't want to go with fully adjustable PAS, a simple addition is to put a switch from the CA-TRQ input to Gnd. If you are configured for AutoTorqPAS, this will let you easily turn off PAS for slow speed maneuvers.

Or - if you don't want to mess with fabricating a switch mount, you can order up a second 3-pos switch and wire it up to the TRQ input to get {100%PAS, 50%PAS, noPAS}. The resistors are 4.7K and can jumper pins in the back of the CA-TRQ/PAS JST connector and hide them under some heatshrink.


Many possibilities...

 

[Merlin]

For me works the Regenerative Button on slow speeds to disable the PAS.

But be Carefull...Pedaling and release the Regen Button will give full Throttle 0,1s
maybe not important on low powered Bikes. Just a little Kick....

I learned it the hard way on a 5KW Throttle ... now i wait a second without pedal and then release the regen button.



Tekle teaches me to play with the gain/speed settings. And i found my personal 98% Perfect Settings WITH Prelim5.

I will Post my Settings next Time i Plug my now Loading BAttery on.
With these Settings i would say it is the Perfect German Throttle Layout


edit: Maybe Tekle can Explain the 3 Switch Mode for PAS Assistant for non Proffessionals?
I see all time Pictures of Electro stuff but what i need is:
take this, take that, take a switch, this wires and solder it

 

[teklektik]

For me works the Regenerative Button on slow speeds to disable the PAS.

Maybe ... explain the 3 Switch Mode for PAS Assistant for non Proffessionals?

Sure - no problem. A question or two first. I'm thinking that you are using a simple PAS wheel, AutoTorqPAS as described here, and we are talking about a 3-position switch with these settings: {100%PAS, x%PAS, and No-PAS}.

1. Do you want the "x%PAS" setting to be adjustable with a little trimpot? This could be the long thin kind that could be part of the cabling and covered with heatshrink except for the screw adjust on the end. Set it and forget it.
2. If you want a fixed value for "x%PAS" instead, what do want for the percentage? I will select some resistors to get as close as possible (For instance 50% or 33%, etc)

Happy to hear you installation has worked out well!
(I tried to add material to the Guide that would cover the questions you brought up - thanks!)

 

[Merlin]

1. Do you want the "x%PAS" setting to be adjustable with a little trimpot? This could be the long thin kind that could be part of the cabling and covered with heatshrink except for the screw adjust on the end. Set it and forget it.
2. If you want a fixed value for "x%PAS" instead, what do want for the percentage? I will select some resistors to get as close as possible (For instance 50% or 33%, etc)

The Trimpot would be the best solution for the "future"

What percentage will be 100%? the Auto-Pas Max Power? Like 500w?
and from this 500w(100%) i will have 50%(250w) and maybe 25%(125W) ?

My experience with my bike is that i need
250w on flat for 25kph cruising.
450w for ~40 kph cruising.

so what i want on a 3 speed switch is:
1: 250w
2: 450w
3: 750w (for Hills)

What happens when iam in "PreSet 2"where the Auto Pas Max Power is Set to 500w? I think the Max will limit the 3 Speed Switch to maximum 500w right?

 

[teklektik]

What happens when iam in "PreSet 2"where the Auto Pas Max Power is Set to 500w? I think the Max will limit the 3 Speed Switch to maximum 500w right?

Yes - 3-pos switch max will be the configured power level, but remember that the max PAS assist is a global parameter and is the same across all presets (level is set by PAS->PASWatts if in AutoPAS mode or Trq->TrqScale if in AutoTorqPAS mode).

To be sure what you have - are you using:

1. plain AutoPAS mode where the max wattage is set by PAS->PASWatts (described on page 29 of the Guide)? Here the 3-position switch is connected to AuxPot which would control PAS level.
2. or the trick AutoTorqPAS mode (assist increases with pedal rpm) where the max wattage is set by Trq->TrqScale (described on page 38 of the Guide)? Here the 3-position switch is connected to the TRQ input and does not use AuxPot which can be used for another purpose (to control throttle current/power or as a preset switch).

Just want to make sure I understand your setup....
(Actually, the switch is built the same for each case, but is just hooked up to a different input - so you could change your mind later if you want...)

 

[Merlin]

iam going with door number 1 for now =)

AutoPAS with 500w max (because PreSet 1 (the Legal one is limited by 25kph) can accelerate with 500w to 25kph. PreSet 2 ( the allday) can go with this 500w to 40-/45kph) Preset 3 has everything open with no PAS.)

When i am able to build this 3 speed switch to set 250-450-750w i would change the AutoPAS max to 750.

Not Perfect for the Legal one....But i would be ok. Maybe in Future Firmware will the AutoPAS Max for Each Preset setable

 

[TreksterJim]

I have been using the CAV3 in the PAS mode. Here are readings from today's ride:
HWhrs 162.1
AvgHW 87
time 2hr10m51s

Dividing the HWhrs by the time yields: 74.3294 average watts. This is different than the CAV3's AvgHW of 87. Why is this?

 

[hjns]

I have been using the CAV3 in the PAS mode. Here are readings from today's ride:
HWhrs 162.1
AvgHW 87
time 2hr10m51s

Dividing the HWhrs by the time yields: 74.3294 average watts. This is different than the CAV3's AvgHW of 87. Why is this?

Probably because you put in some peak Whrs. Having a lot of low Whrs, and only some peak Whrs will result in a lower average Whrs, whereas total Whrs is the same.

 

[TreksterJim]

I have been using the CAV3 in the PAS mode. Here are readings from today's ride:
HWhrs 162.1
AvgHW 87
time 2hr10m51s

Dividing the HWhrs by the time yields: 74.3294 average watts. This is different than the CAV3's AvgHW of 87. Why is this?

Probably because you put in some peak Whrs. Having a lot of low Whrs, and only some peak Whrs will result in a lower average Whrs, whereas total Whrs is the same.

I am referring here to average watts not watt-hours (Whrs). Shouldn't dividing watt-hours by hours be the same as the watts (AvgHW) reported by the CAV3?

Jim

 

[hjns]

Sorry for my confusing previous post.

Capacity (Wh) = Power (W) * Time (h)

Let's assume you give a very constant 50 W for 1 hour, you would have spent a total Capacity of 50Wh. Your average Power would be 50 W as well.

Now, let's assume you give a very constant 40 W for 1 hour (40 Wh), and a single high power effort of 100 W for 6 minutes (100W*0.1h= 10Wh). That would be the same as 40 Wh + 10 Wh = 50 Wh during a period of 1.1h This would bring your average Power of 45.5 W, even though you spent exactly the same 50 Wh as in the first example.

It follows that your average power does not reflect the total energy capacity because it is really dependent on how you distributed that power during the time you spent it.

 

[TreksterJim]

It follows that your average power does not reflect the total energy capacity because it is really dependent on how you distributed that power during the time you spent it.

I totally agree with this statement. However perhaps my original post was confusing and misunderstood.

After one of my rides I noted the following reading:
Human watt-hours (HWhrs): 162.1
Average human watts (AvgHW): 87
Time: 2hr10m51s
View attachment 1

Perhaps some of the confusion in my previous post was due to a misinterpretion of the AvgHW value. I think AvgHW means average human watts and not average watt-hours.

So back to my original question. Why do I come up with a different average human watts value if I divide the reported human watt-hours by the reported time.

This discrepancy happens on every ride. Is this due a glitch in the CAV3's firmware or am I not reading the results properly?

Thanks for your help.
Jim

 

[cloudcover]

There is no means for the bike to 'know' how much power is required to accomplish the task, whether you are assisting or not. How does it know if adding 5 Amps or 50Amps of assist is doing the job?

yeah, sorry, my question was quite poorly worded. maybe this will help. in thinking about it further, the "feel" i'm looking for is that i'd like to be able to pedal at a given/constant cadence but have my pedaling effort not exceed a certain maximum. the analogy for a non-motorized bike would be shifting down in gears so as to keep pedaling torque below some comfort level. i'm interested in a more automated version of that with an ebike, where i can choose a gear on my bike and then just pedal at a constant cadence with the motor adding in power to keep my pedaling torque from getting too high. that's why i thought that maybe a torque sensor could help. i thought that maybe if it sensed that the torque exceeded some threshold, it would increase the motor power until that pedaling torque decreased back to below the threshold. does that help clarify what i have in mind? or is it still asking too much of electronics? :?

also, maybe another way for me to understand how the v3 works with the thun sensor: what's the cycling "feel" from that setup? how might you describe it in relation to a non-motorized bike?

thanks again!

 

[Kepler]

one more thing to mention: pas-torque works GREAT. just as i was always wanted that feature to be. pedal slow and you get a little support, pedal fast and you fly
what did not work to my satisfaction was the almost instant full power. even 500w kicking in can be way too much when maneuvering. then i rethought it, and set "ThrO -> Up Ramp" back to 2s/V. now it's super smooth. but of course this makes the thumb throttle super laggy as well. maybe those two could be adjustable seperately?
i know i ask for much, and this makes setup even more complicated, but i think it's more convenient to have throttle ramp up/down be different for pas and thumb/twist throttle.
btw: setup right know is REALLY complex. and i LOVE it. it's a real geek gadget if you want it that to be

I had the same thing with my 3000W Fighter. Thumb throttle was too mushy once I had AutoTquPAS dialed in. To improve the thumb throttle feel I set the UpRamp to 1.0S and the fastRamp to 0.5S. I then used Wgain to tone it down. Set Wgain to 15 on mine. This gave me good throttle response and smooth PAS.

Also found that setting the downRamp to 0.5S smooths things out a bit without sacrificing throttle response.

 

[izeman]

@kepler: thanks. will try that. another annoying thing (which may go away with your settings) is, that you pedal, get assistance, decide you need more power, push the throttle, and the power does what? IT GOES AWAY. then comes back. i wish the throttle would just add up to the level that is already present w/o cutting the power first for (half?) a second.

 

[Merlin]

yep, here same. hope this can be fixed.

with high ramp up time (2sec) it sucks alot, because pushing throttle will start the ramp up time "again"...

 

[izeman]

yep, here same. hope this can be fixed.

with high ramp up time (2sec) it sucks alot, because pushing throttle will start the ramp up time "again"...

should be easy to solve. if there is already a throttle signal then start using this output value and not zero. at least this is how i think it could be done

 

[Kepler]

@kepler: thanks. will try that. another annoying thing (which may go away with your settings) is, that you pedal, get assistance, decide you need more power, push the throttle, and the power does what? IT GOES AWAY. then comes back. i wish the throttle would just add up to the level that is already present w/o cutting the power first for (half?) a second.

Yep, I get the same thing too. This is where I found the downRamp helps. Its not the answer but it helps. I made a few similar suggestions to improve this to tek. Good to know we are on the same page. Last thing Justin wants to be doing is fixing problems for one off cases.

 

[teklektik]

Maybe Tekle can Explain the 3 Switch Mode for PAS Assistant for non Professionals?
I see all time Pictures of Electro stuff but what i need is:
take this, take that, take a switch, this wires and solder it

1. Do you want the "x%PAS" setting to be adjustable with a little trimpot?
2. If you want a fixed value for "x%PAS" instead, what do want for the percentage? I will select some resistors to get as close as possible (For instance 50% or 33%, etc)

The Trimpot would be the best solution for the "future"

...what i want on a 3 speed switch is:
1: 250w
2: 450w
3: 750w (for Hills)

Merlin-
Apologies for the delay - I looked at a few different means to accomplish this and tried to select something that would be simple to construct and useful for other folks who want a 3-position switch but with different values. The next post describes a solution that uses fixed resistors but is adjustable via V3 Setup.

The idea is similar to the trick used in this post about throttle curve shaping for the V3 where the MIN and MAX values are adjusted to move an interesting part of a response curve into a relative voltage range where the CA can use it.

This approach lacks the appeal of trimpots, but with the settings table provided below, it's not very difficult to do the one-time setup. Hope this moves your PAS efforts along a bit...