Cycle Analyst V3 preview and first beta release

[Hyena]

Sweet, I should have known Justin would be all over such a thing

 

[electricwheels.de]

How cool would it be to wire up the e-brake cutoff to your trigger shifters,...

D'oh!
This is a much simpler solution than (1) or (2) that I mentioned in the post above about shifter/interrupters. I automatically shy away from involving the ebrake inputs because of DD regen considerations, but I didn't think this through - regen cannot be a consideration in the mid-drive case. The ebrake approach has the advantage of involving the CA in ramping/gain control.
Tidy and nifty!

A and 8) idea

 

[efergy kb]

I read the below again and again... and tried testing some different settings however i clearly have no idea what i am really doing...
The initial settings on this were primarily and the Up Rate and Fast Rate were about 20.00Vlt/sec which from reading the post below; was basically WOT on acceleration; hence wanted this to be lower and smoother. Most of the configuration here are 'as-is' and not been modified...

Issue:
- As per RC_guy post below; the initial acceleration is quite jerky. After it hits about 20km/hr - acceleration smooths out
- At 33% (Low speed switch); you can feel the sudden surges and loss in power in like 1 second waves until it hits 20km/hr speed..
- At 66% (Med speed switch); the acceleration seems to be better; there is a more gentlier and you can just notice the loss in power before the acceleration smooths..

My Setup:
MAC8T, 12fet 25A, 50V 12.3Ah Samsung Triangle Pack 14S6P)
- Have a CA v3, and 3 speed switch attached. Controller is limited to 33% Low, 66% Medium, 99%High speed. Also current is limited to 30A.

Cycle Analyst v3 settings: I have no idea so i thought i'd post as much as i ca
Setup ThrotIn 0.80V 13% Thru
ThrI - Cntrl Mode: Pass-thru
ThrI - Min Input: 0.3Volt
ThrI - Max Input: 4.2Volt
ThrI - FaultVolt: 4.49Volt

Setup ThrotOut 0.83 - 4.20V
ThrO - Output Mode: Voltage
ThrO - Min Out: 0.83 V
ThrO - Max Out: 4.2V
ThrO - Brake Out: 0.0V
ThrO - Up Rate: 3Vlt/sec
ThrO - Down Rate: 19.99Vlt/sec
ThrO - Fast Rate: 9.99Vlt/sec
ThrO - Fast Thrash: 0.1 Amp

Setup Max Speed: 70kph
Slim - IntSGain: 50gain
Slim - PSGain: 1.0V/kph
Slim - DSGain: 100gain

Setup Power Limit: 25A 2000W
PLim - Max Current: 23A
PLim - AGain: 30Gain
PLim - Max Power: 2000Watts
PLim - WGain: 50gain

Setup Aux Po 2.39V 74% Pwr
Aux - Function: Limits
Aux - Scale Lim: Power
Aux Min Aux In 0.0V
Aux Max Aux In 3.2V

I had to turn down the power gain to 30 to remove the jerkiness. Is this normal?
...
One thing I would like to tweek is that I find it difficult to give just a little bit of throttle. Even if I apply only a tiny bit, it gives about 15 amps. Once I get going then it will decrease and it is easier to modulate but, as soon as I get back on the throttle, it still wants to give more than I want.

Well - jerky starts aren't desirable but they can be 'normal' for a higher torque rig (eg MAC) that needs a little tuning.

Here's your earlier settings:

Up Rate = 21 V/s
Down Rate = 50.1V/s
Fast Rate = 24V/s
Fast Thrsh = 3 Amps

Max Current = 45 amps
AGain = 80

There are a few things in play here that can contribute to jerky starts:

1. An aggressive FAST START setting for ramping.
   Fast start can be tricky to set up properly so that it works well under all driving conditions - particularly if you are using PAS or looking for very low power getaways on bike paths or to walk the bike. Part of the problem is that the default setting of ThrO->FastThrsh = 3A is a whooping large power level to achieve before the ramping logic switches over to the 'slow' ramp defined by UpRate. I recommend that you set FastThrsh = 0 to start and address this fast start optimization after you are happy with the entire remaining setup and performance. This will disable the FAST START feature completely and the CA will rely entirely on UpRate.
   
   Particularly for PAS, this can immediately remedy the startup surge. I used no FastRate for well over a year and only recently began using it with FastThrsh = 0.20A.
   
   
2. High UpRate setting.
   Let's look at what the various xxRate settings mean: The ramping is a clamp that prevents the throttle output from exceeding the configured rate. It is not in play for slow increases/decreases that do not exceed those rates. A typical throttle has a range of about 3v so a rate of 3v/sec means if you slam the throttle ZERO-to-WOT in PassThru, the ramping will hold back the throttle application so that it takes 1sec to traverse the 3v range. 6v/sec will take 1/2sec, and in your case, 21v/sec will take only (3v)/(21v/s) = .14sec (PDQ! - very little ramping at all).
   
   Here we get into matters of riding style, vehicle weight, motor torque, and drivetrain type so there is no 'correct setting' and examples may be no more useful than the default setting. That said - for a MAC (torquey and with breakable clutch) I think you might turn your ramping down a lot - to something in the 1v/s - 5v/s region. That might be excessive, but you get the idea - you are presently way up there... (I actually run lower than that but my bike is heavy with two over-volted gear motors and I use the motors to jackrabbit from dead stops across intersections - no special driving practices necessary to protect the clutches - just slam WOT with no manual feathering. )
   
   
3. High AGain setting.
   You describe an overshoot siutation where the initial power seems high but then moderates when underway. That's a bit hard to interpret but in conjunction with your AGain setting of 80, it seems you are describing an overshoot situation. Here the CA looks at the 'error' between the current you requested by turning the throttle and the actual current and applies a correction to the throttle voltage to correct. The magnitude of that correction is controlled by the coefficient AGain. If this is too large, the CA applies a whooping big correction that causes an overshoot. If this is too small, the correction is very slow or possibly even insufficient to achieve the target. So the trick is to get a balance that seems to work 'best' generally. I would recommend cranking it down to 10 and increase it from there. At 10, the throttle will be pretty laggy, but the overshoot should be gone and you can quickly work back up to a more desirable setting.
   
   
4. Non-linear throttle output.
   In the end, the CA Current Throttle guarantees that the battery current will exactly track the throttle voltage - which for a perfect throttle is nicely linear with rotation (e.g. 25% rotation = 25% max throttle voltage). However, crappy hall throttles have non-linear rotation-to-voltage curves and so even though the CA performs as advertised, the throttle response has steps or deadish zones. Here you need to get a more expensive hall throttle like the Wuxing that has a single linear magnet (instead of two magnets and a non-linear magnetic field between them) or a resistive throttle like a Magura.
   
   
5. Varied driving scenarios.
   At the end of the day, even with a nice linear throttle response, you may find the throttle response insufficiently refined at the beginning for walking the bike or comfortable low speed operation. The problem is that for a multi-thousand Watt bike, even a linear throttle makes control of a few percent of the total power difficult or tiring.
   
   Enter the CA 3-position switch. This allows you to cut the power for different types of driving situations. If your bike has a max current of 60A and your switch selects 25% current then the max current the CA will allow is 15A. With Current Throttle, a 33% throttle rotation will apply only 5A. This gives refined and easy to control operation. If you don't have one, this may help out low speed operation if that is presenting an unpleasantness. These switches can be flipped on the fly under power, so the inevitible 'Oh crap!' situation won't leave you strapped for power. I have a 3-position switch rigged for low power bike path use, full speed cruising (motor-won't overheat-at-WOT), and flank speed (aka boost! - motors will overheat if applied too long).
   
   Although the analogy is severely flawed (current vs gearing), this is not unlike driving in 1st in the parking lot and shifting to 5th on the highway. The point being that there is some explicit operator selection of the drivable speed range...

Is there a way to change the throttle curve?

Actually, yes. Changing the throttle curve is quite simple to do with a few resistors if you have a resistive throttle like a Magura. The procedure is described in this post. I never got any feedback on this and so didn't include it in the Guide as perhaps being a little too tweaky for the average user in spite of the simple construction.

 

[izeman]

i also play a lot with throttle ramping and different throttle mode (current, power, pass-thru) but am not happy.
the mid driver per se has a lot of lag. the motor has to turn, then there is the reduction gearing, and lastly the chain.
so if you are in a low gear and apply 2kW it's hard to apply that little throttle so the bike just won't flip over. if you add some throttle lag (slow up-ramp) it becomes better, but then it's hard to controll as soon as the bike is moving. twisting the throttle now is so slow that it takes too much time until power is applied. is there a way to tell the throttle act differently depending on speed? (and i don't think that speed-mode is the right throttle mode for that).
so what is would like to see: some kind of exponential throttle signal. and some damping. if you turn it slowly and only a bit from the start there is very little power applied. if you turn it WOT you apply a lot of power immediately.

 

[teklektik]

Issue:
- As per RC_guy post below; the initial acceleration is quite jerky. After it hits about 20km/hr - acceleration smooths out
- At 33% (Low speed switch); you can feel the sudden surges and loss in power in like 1 second waves until it hits 20km/hr speed..
- At 66% (Med speed switch); the acceleration seems to be better; there is a more gentlier and you can just notice the loss in power before the acceleration smooths..

My Setup:
MAC8T, 12fet 25A, 50V 12.3Ah Samsung Triangle Pack 14S6P)
- Have a CA v3, and 3 speed switch attached. Controller is limited to 33% Low, 66% Medium, 99%High speed. Also current is limited to 30A.

Cycle Analyst v3 settings: I have no idea so i thought i'd post as much as i ca
Setup ThrotIn 0.80V 13% Thru
Setup Aux Po 2.39V 74% Pwr

It seems you have lots of EM3EV parts so I'm guessing you got the V3 from there as well. Paul sets up a number of parameters in the V3 so it should arrive in a fairly workable state.

However, just looking at what you have typed, it seems that there are errors in the basic setup - before we get to ramping, etc.

1. The Throttle In settings are incorrect so your bike should be motoring along pretty quickly at ZERO throttle. Since you don't complain of that, the Throttle Out settings must also be wrong. Beyond the wonky values, this is easy to see because the CA reports 13% throttle (blue underlined above) at ZERO throttle instead of 0%.
2. The Aux Pot is incorrect so your Power limits are not the 33%/66%/99% you claim. This must be true not only because of the odd values in the Aux setup, but because of the 74% power limit shown (green underlined above) which should only be exactly one of 33%/66%/99%.

These need to be corrected up front. Please do these things:

1. restore the file with the saved EM3EV settings from section 4.1 of the Guide. This will restore the bike to 'as delivered' condition and undo any tinkering you have done.
2. follow the steps in sections 4.6 and 4.7 of the Guide. This will get your bike to known state and will get the throttle set up properly.
3. follow the steps in section E.1 to set up your AuxPot. Set it for current limiting.

Please post back your settings when this is successfully accomplished, or post if there are any parts of those steps that require further explanation.

Get that squared away and we can move on to other settings...

• FWIW: It's easier if you just save the settings to a file using the Setup utility as described in this post, change the extension to '.txt' and post the file up here. There is no chance of error and involves a heck of lot less typing - that said, you seem to have covered the important bases above doing it manually - but....

 

[teklektik]

i also play a lot with throttle ramping and different throttle mode (current, power, pass-thru) but am not happy.
the mid driver per se has a lot of lag. the motor has to turn, then there is the reduction gearing, and lastly the chain.
so if you are in a low gear and apply 2kW it's hard to apply that little throttle so the bike just won't flip over. if you add some throttle lag (slow up-ramp) it becomes better, but then it's hard to controll as soon as the bike is moving. twisting the throttle now is so slow that it takes too much time until power is applied. is there a way to tell the throttle act differently depending on speed? (and i don't think that speed-mode is the right throttle mode for that).

This matter of more powerful mid-drives came up in recent posts and although the V3 works pretty well with modest power mid-drives (eg EdgeRunner and StokeMonkey), really powerful units are an area where there is not a lot of experience.

Anyhow, I would recommend that you use Current Throttle to get the best throttle/applied power relationship. Get AGain adjusted to minimize surging. Then go back and try playing with ramping. Here you might tinker with FastRate and FastThrsh - these are designed to apply a 'faster' ramp rate until the slop is taken up in your drive system at which time the increased motor current will exceed FastThrsh and the ramp rate will reduce to UpRate.

Frankly, I think some work may be required in the firmware to better handle the FastRate/UpRate changeover, but for now it is what it is....

You should not be messing with Speed throttle or any speed settings they do not in any way affect the ramping/gain/throttle issues you report. There are presently no means to have speed (or more rightly 'gear') play a role in ramping or Gain. The hub-motor vs mid-drive heritage of the V3 may be showing in these newer mid-drive builds and perhaps some enhancements to better address these different drive trains will be required. That said, some kind of a gear detector (perhaps as described in a recent post) might be applied to AuxPot to reduce the power in low gears to get the extreme torque under better control in the manner of an automatic 3-position (7-position) switch. In any case, please post back with your experiences so issues get some exposure, even if they cannot be immediately remedied 100%.

so what is would like to see: some kind of exponential throttle signal. and some damping. if you turn it slowly and only a bit from the start there is very little power applied. if you turn it WOT you apply a lot of power immediately.

As mentioned in a recent post, it is fairly simple to get throttle mappings similar to what you desire.

Is there a way to change the throttle curve?

Actually, yes. Changing the throttle curve is quite simple to do with a few resistors if you have a resistive throttle like a Magura. The procedure is described in this post. I never got any feedback on this and so didn't include it in the Guide as perhaps being a little too tweaky for the average user in spite of the simple construction.

Sample curves that can be accomplished with a few resistors as described in that post:

 

[izeman]

thanks teklektik. i will try asap and post my findings. i know about the resistor mod but unfortunately i have a hall throttle so i can't use it.

 

[Wheels_78]

Can anyone tell me what the maximum torque assist level is on the CA3? Looks like it can be set to 99, but I'm assuming it's something less than that... or maybe not. Thanks.

 

[izeman]

i should have read that better. i don't know how often i flew over these lines and never may have understood it.

FastThrsh sets the FastRate to UpRate switchover current.
• If FastThrsh = 0.00A, FastRate is ignored and UpRate is always employed, otherwise:
• When current is less than FastThrsh, the CA uses FastRate to allow the motor to quickly come to speed.
This is useful for gear motors or mid-drives when re-engaging a freewheel if already underway.
• When current is FastThrsh or greater, the CA uses UpRate – typically to apply slower ramping.

i thought that this would make throttle response SLOWER as long as current has not reached a particular value. but it was the total opposite

 

[teklektik]

i should have read that better. i don't know how often i flew over these lines and never may have understood it.

The difficulty may be that although it is accurate, it may not be entirely revealing as to the effect.
Perhaps a little re-write is in order....
Thanks for your comments!

 

[teklektik]

Can anyone tell me what the maximum torque assist level is on the CA3? Looks like it can be set to 99, but I'm assuming it's something less than that... or maybe not. Thanks.

I see from your thread that you have an unusual Thun application in a hand cycle. I'm not sure if this introduces any special considerations on the Thun regarding operating torque range or hands vs feet - the hands construction does have longer effective levers to multiply the human torque and the minimum cadence assumption (55rpm) may not be spot on...

Anyhow, to set the stage - the Guide describes the calculation:

16.Torque-based PAS – Operation:
The CA takes the BB torque voltage, subtracts Trq->TrqOffst to normalize the voltage relative to the zero-torque signal level, and multiplies the result by Trq->TrqScale to convert to Nm of torque. Using this torque with the larger of 55rpm or rider cadence, it calculates the rider contribution in 'Human Watts'. It subtracts Trq->AsstStart from 'Human Watts' and multiplies the result by Trq->AsstFactr to determine the assist power to deliver. An external switch or pot hooked to the AuxPot input scales Trq->AsstFactr 0-100% to give adjustable assist based on the rider torque and cadence. The determined assist level is used to control the motor using the Power PID controller which is configured by PLim->MaxPower and PLim->WGain.

The Thun can detect a torque of up to 200Nm which corresponds to a torque voltage of about 4.5v with a Trq->Offset of 2.5v yielding a 2v range for 0-200Nm. The V3 'Thun' setting uses a fixed Trq->TrqScale = -200Nm/V to yield the proper voltage-to-torque conversion (-100Nm for the base Thun conversion and a fudge factor of 2x to account for only measuring torque on the left pedal side).

As described above, the CA works in the cadence and the Trq->AsstStart setting and arrives at a 'Human Watts' figure. This is multiplied by Trq->AsstFactr to derive the 'Motor Watts' of assist to apply (scaled by AuxPot Assist level if present).

At the end of the day, your final assist level is affected by two primary multipliers: Trq->TrqScale (which was chosen to scale the Thun output over the entire Thun torque range) and Trq->AsstFactr. AsstFactor has a max value of '99.99 times' (finally got to your question!). Assuming your rig can apply 2000W of battery power and using an Assist Factor of 100, you could achieve that maximum assist by generating 2000W/100 = 20W of human power. So - even though the range is limited to 99.99x, the achievable maximum assist is substantial - for feet.

Are you experiencing a shortfall in assist power because of hand propulsion (ie insufficient detected Thun torque or cadence)?

BTW - You should add a 'Hand Cycle' link to your signature - nice build with interesting considerations!

EDIT - The Thun default value above was corrected after a conversation with Justin - my Bad!

 

[Wheels_78]

Can anyone tell me what the maximum torque assist level is on the CA3? Looks like it can be set to 99, but I'm assuming it's something less than that... or maybe not. Thanks.

I see from your thread that you have an unusual Thun application in a hand cycle. I'm not sure if this introduces any special considerations on the Thun regarding operating torque range or hands vs feet - the hands construction does have longer effective levers to multiply the human torque and the minimum cadence assumption (55rpm) may not be spot on...

Anyhow, to set the stage - the Guide describes the calculation:

16.Torque-based PAS – Operation:
The CA takes the BB torque voltage, subtracts Trq->TrqOffst to normalize the voltage relative to the zero-torque signal level, and multiplies the result by Trq->TrqScale to convert to Nm of torque. Using this torque with the larger of 55rpm or rider cadence, it calculates the rider contribution in 'Human Watts'. It subtracts Trq->AsstStart from 'Human Watts' and multiplies the result by Trq->AsstFactr to determine the assist power to deliver. An external switch or pot hooked to the AuxPot input scales Trq->AsstFactr 0-100% to give adjustable assist based on the rider torque and cadence. The determined assist level is used to control the motor using the Power PID controller which is configured by PLim->MaxPower and PLim->WGain.

The Thun can detect a torque of up to 200Nm which corresponds to a torque voltage of about 4.5v with a Trq->Offset of 2.5v yielding a 2v range for 0-200Nm. The V3 'Thun' setting uses a fixed Trq->TrqScale = 25Nm/V to yield the proper voltage-to-torque conversion; so for a voltage range of 2.5v to 4.5v the V3 calculates a maximum torque of 0 to (4.5v-2.5v)*(25Nm/V) = 200Nm -- exactly as specified.

As described above, the CA works in the cadence and the Trq->AsstStart setting and arrives at a 'Human Watts' figure. This is multiplied by Trq->AsstFactr to derive the 'Motor Watts' of assist to apply (scaled by AuxPot Assist level if present).

At the end of the day, your final assist level is affected by two primary multipliers: Trq->TrqScale (which was chosen to scale the Thun output over the entire Thun torque range) and Trq->AsstFactr. AsstFactor has a max value of '99.99 times' (finally got to your question!). Assuming your rig can apply 2000W of battery power and using an Assist Factor of 100, you could achieve that maximum assist by generating 2000W/100 = 20W of human power. So - even though the range is limited to 99.99x, the achievable maximum assist is substantial - for feet.

Are you experiencing a shortfall in assist power because of hand propulsion (ie insufficient detected Thun torque or cadence)?

BTW - You should add a 'Hand Cycle' link to your signature - nice build with interesting considerations!

Thanks for the comprehensive answer! To answer your question, "sort of".

I'm finding two things...

1. The assist tends to come in pulses, I presume this is primarily because of low cadence I increased the torque average from 8 to 16 and this was helpful but did not eliminate the problem. I have increased it to 24 but haven't ridden it again yet. I'm confident that eliminating this is just going to be a matter of finding the right trqavg/throttle down rate combination.

2. I'm not seeing substantial assist until I'm in a higher gear than I'd like to be and really grunting on the cranks. This is hard on the joints etc. and as you may guess my arms and shoulders are pretty important to me. I didn't realize the trqscale multiplier could be mucked with but I presume that if I did that it will effect the accuracy of the calculated human watts etc. and I don't want to do that. Sounds like I just need to up the assist factor until it behaves as I'd like it to.

I was just wondering if there was a practical limit to the setting that was lower than digital limit would indicate. Sounds like there isn't. I'll set it to 99 with a pot to adjust it on the fly and see where I tend to like it when I'm in need of the most assistance, I can start guess and check tuning from there.

 

[teklektik]

2. I'm not seeing substantial assist until I'm in a higher gear than I'd like to be and really grunting on the cranks. This is hard on the joints etc. and as you may guess my arms and shoulders are pretty important to me. I didn't realize the trqscale multiplier could be mucked with but I presume that if I did that it will effect the accuracy of the calculated human watts etc. and I don't want to do that. Sounds like I just need to up the assist factor until it behaves as I'd like it to.

I was just wondering if there was a practical limit to the setting that was lower than digital limit would indicate. Sounds like there isn't.

Nope - no limit - have at it!

Some thoughts:

• I'm guessing that your 'hand cadence' is far lower than the typical 'foot cadence' of 60-120rpm. The V3 assumes a minimum rpm of 55 when it does the 'human power' calculation which is fine since it ensures a small kick in the pants to get rolling off the line and folks don't typically pedal so slowly. However, if your cadence range is something like 30-70rpm (for example) then there are two immediate effects:
  • You 'human watts calculation is way off since the slowest the CA thinks you can row is 55rpm
  • You are not getting any rpm power scaling until you are mid-rpm-range. Since power is related to the product of RPM and TORQUE you are relying heavily on torque scaling and missing the added power that might be applied by downshifting (reduced torque but higher rpm).
  So - I'm thinking that since the 55rpm limit is not adjustable, you might trick the CA by reducing your pole count. Since the Thun pole setting is 8, you might (for the 30-70rpm example) reduce this to 4. Some adjustment of the start/stop thresholds would also be required. With this setting, when you row at 30rpm, the CA will think you are waling away at twice that or 60rpm. This would supersede the 55rpm limit and you would immediately be getting rpm-scaling as you rowed faster. This should make downshifting more attractive as the assist should increase. Since your 'human watts' figure is already bogus because of the 55rpm limit, this change will actually improve things since it will now be accurate but twice actual. Just a thought....
  
  EDIT - Justin points out that this is not exactly true. Although 55rpm is indeed used as the minimum rpm for Assist Power calculations, the true rpm is used for display and logging of Human Power so Human Watts is accurate in spite of cadence falling below 55rpm. Thanks J!
  
  
• You mention in your thread:
  

  ...this is very close to what I want but I was still forced to rely on the throttle on hills if I didn't plan ahead and set the assist factor up.
  ...
  Tonight I'm going to set the throttle up on the aux port to be an on the fly assist adjustment, ...

  You didn't explain the details, but you don't want to get into a situation where you are holding the assist level like a throttle - otherwise just use the throttle. But - you really do need to get the assist level control set up so you can diddle it on the fly.
  
  Looking at your build I'm thinking that adding a stub bar to the left rowing handle (similar to the one on the right that mounts brake, etc) might be a good plan and you could add the assist level control there. You might use a 1/2 twist or thumb throttle with the spring removed (see this post (use o-rings for drag)) but these have a short throw and the adjustment may not be as refined as desired. Another idea might be to use a friction shifter hooked to one of gwhy!'s hall throttle boxes.
  
  
  I use a DIY bar-end pot which is pretty convenient and has the long adjustment range of a regular pot, but I'm actually thinking that a nice solution for you might be something like an L-bracket at the top of the rowing handle with a pot mounted horizontally (orthogonal to mine shown below). A plain barrel knob would appear as a simple thumb adjust so you keep rowing but just pop your thumb up onto the barrel and roll it up or down a bit....
  
  

BTW - I see you added some links in your signature (cool) - but you should put those in the build thread and put a link to your build thread in the signature! Then we can track down your handiwork when you post...

 

[Wheels_78]

So - I'm thinking that since the 55rpm limit is not adjustable, you might trick the CA by reducing your pole count. Since the Thun pole setting is 8, you might (for the 30-70rpm example) reduce this to 4. Some adjustment of the start/stop thresholds would also be required. With this setting, when you row at 30rpm, the CA will think you are waling away at twice that or 60rpm. This would supersede the 55rpm limit and you would immediately be getting rpm-scaling as you rowed faster. This should make downshifting more attractive as the assist should increase. Since your 'human watts' figure is already bogus because of the 55rpm limit, this change will actually improve things since it will now be accurate but twice actual. Just a thought....

That is a great idea! Not hard to tell you're more than just passing familiar with this system.

You didn't explain the details, but you don't want to get into a situation where you are holding the assist level like a throttle - otherwise just use the throttle. But - you really do need to get the assist level control set up so you can diddle it on the fly.

I have modified the throttle, turns out that if you don't have O-rings a couple zip ties are enough friction to work as well :wink:

Looking at your build I'm thinking that adding a stub bar to the left rowing handle (similar to the one on the right that mounts brake, etc) might be a good plan and you could add the assist level control there. You might use a 1/2 twist or thumb throttle with the spring removed (see this post (use o-rings for drag)) but these have a short throw and the adjustment may not be as refined as desired. Another idea might be to use a friction shifter hooked to one of gwhy!'s hall throttle boxes.

Due to the nature of how those handles and cranks move while pedaling I'd be nervous about the longevity of any wiring run up there, but it would be damn nice to be able to adjust assist level without taking my hands off the cranks... I'll have to give that some thought. If you have any ideas I'd love to hear them but that might be better discussed in the other thread.

 

[Wheels_78]

Just wanted to post up a thanks!

Got a chance to take the bike out for a quick run just now after switching the pole count to 4 (your recommendation had been just about dead on, the average pedal RPM from the previous ride was 55.9) the bike is a completely different animal I can get assist even when I'm not accelerating and hill climbing isn't all about getting enough speed at the bottom to make sure I can white knuckle it to the top without stopping... I can accelerate on hills. I was also able to cut the assist level I'm using in half as opposed to increasing it, not that the battery will know the difference but it shows you were right.

 

[teklektik]

...the bike is a completely different animal...

This is wonderful news!
You have a very unique and interesting V3/Thun build - very satisfying to see it coming together.
Many thanks for posting back.

BTW:

• Justin pointed out a couple of errors in details of the above posts - I have revised and noted the changes (default Thun scaling value and use of the 55rpm minimum for Power Assist vs Human Watts calculations). Oops!
  
  He also recommends that you might it useful to adjust Trq->AsstStart to some negative value so that there will be some baseline power applied as soon as pedaling is detected - even with no torque applied. I was concerned about this if you use PAS for slow maneuvering but should have called it out for experimentation. Good to try!

 

[izeman]

any update on cell vs pack voltage display? or an alternating cell voltage (total pack divided by cell number) and pack voltage?
i still can't get used to the total pack voltage. i now wrote down some numbers as i just can remember them when on the road.
50v = super. 42v = time to stop. but how could i say that 46.2v is 3.85v per cell and a good number to not touch the battery after a ride as this is storage voltage for my rc-lipo.
for those not wanting this feature you still can make it configurable:
1) show pack voltage
2) show cell and pack voltage alternating
3) show cell voltage only
and for those who didn't follow former posts: i know that the CA doesn't know a particular cell voltage. it's just that the CA should do the math for me to give me a rough indication on battery soc.

 

[Alan B]

+1 on cell voltage display mode/choice/??

 

[mrbill]

Folks:

I just noticed an inconsistency in the human average power/energy calculation. The problem appears to have been present for a long time, but I didn't notice it because I never bothered to check the calculation myself until now.

The CAV3 (Prelim6) gives three data,

HWhrs
AvgHW
TripTime (that I assume is moving time and is the basis for the calculation) converted to hours

So, knowing any two of these one should be able to calculate the third.

HWhrs = AvgHW * TripTime
AvgHW = HWhrs/TripTime
TripTime = HWhrs/AvgHW

As I keep careful records of my rides, I have checked several of these, and for each of these rides the calculation is inconsistent.

Example from a recent ride:

The CAV3 (Prelim6) gives me the following stats at the end of a ride:
AvgHW = 164 w
HWhrs = 717.0 wh
TripTime = 6:13:47 = 6.22972 hours

Calculating AvgHW gives:
AvgHW = 717.0/6.229722 = 115 w

Calculating HWhrs gives:
HWhrs = 164 * 6.229722 = 1022 wh

Calculating TripTime gives:
TripTime = 717.0 / 164 = 4.3719512 hours = 4:22:19

Each of these calculations yields a figure that is significantly different from that displayed on the CA screen. I do not know which of these is in error, or for that matter which is correct.

Is this a known bug for which a fix is in the next firmware release? If not, could someone please independently verify this and report back to the forum?

Thanks.

After an email exchange with Justin about this, I now understand how the summary human power statistics are calculated. Please disregard my speculations quoted above.

TripTime is not used to calculate human power summary statistics.

A statistic, PedalingTime, is stored stored internally but is not displayed on the CA V3. PedalingTime is defined as the time during which the cranks are rotating above the threshold RPM (StartThrsh or StopThrsh) so as to read non-zero RPM on the CA V3.

HWhrs are correctly displayed on the CAV3 and are calculated by integrating hwt over time.

AvgHW is calculated as HWhrs/PedalingTime.

PedalingTime = HWhrs/AvgHW.

hwt is the power produced at the pedals during PedalingTime. Reverse crank rotation is treated as zero RPM by the CA V3.

TripTime can be zero while PedalingTime is non-zero such as when riding a bike on a stationary trainer.

 

[chilau2000]

Hi

Looking for some help with my cycle analyst v3.
Tried flashing it to the latest firmware with v1.2 update tool today but it only gets to about 60% then fails on comms error.
Now just have a blank screen on the cycle analyst.
Not sure what firmware it was running before, it did have prelim on the start up screen.
Tried the caloverwrite method with the v1.2 setup utility but I get no cycle analyst found.
I am using a generic usb to ttl adapter that works fine on other devices, changed some settings on a bafang bbs02 with it the other day.

 

[efergy kb]

I have the CAv3 working well, I got it from em3ev with the battery. Firmware is V3.0 Prelim6.
I'd like to connect to it from the computer to run the setup config utility. However I forgot to order the relevant USB programming cable. I already have a usb to serial adapter, so have wired up a 3pin earphone jack with GND, TXD and RXD to match the picture http://www.ebikes.ca/product-info/grin-products/cycle-analyst-3.html

When trying to connect with the utility the CA shows PC CONNECTION but it hangs on "Attempting to connect to the cycle analyst" and I get the error "Unable to read data from the cycle analyst". I have tried cycling the power and trying again to no avail.
Using a Win8 PC. Was able to use the same serial adapter to program my controller happily.

Hi all, after finally getting some time to play with the CA/ Controller again
i am having the same issues at delphinus above. Bought the kit from EM3EV '13 so i'll assume it has the latest firmware (CAV3 Prelime6 Hex File); nevertheless - i am trying to flash it anyways and also get the CA settings out.

I have yet to try this on another PC; however i am using VMWARE with Windows7 inside a MAC.
It wont connect to the Firmware update tool nor the Software Setup Utility - not too sure if anyone has gotten something similar to this and was able to overcome this. I've been able to successfully program the Infineon 12fet controller via VMWARE (Win7) so it may not necessarily be a 'COM' issue...

From the Software Setup Utility; once i click on 'Read Setup from Cycle Analyst'
We can see that the COMM port has been detected (in this case COM4)
As soon as i click 'OKAY'
The Software Setup Utility shows: 'Attempting to connect to Cycle Analyst'
The Cycle Analyst displays '...PC CONNECTION'
After the 30seconds, the Software Setup Utility displays: ERROR:
'Failed to read setup from Cycle Analyst! Please make sure you have selected the correct COM port and that your CA is turned on properly'

If i reboot the Cycle Analyst whilst the Software Setup Utility shows ''Attempting to connect to Cycle Analyst'
ie. (boot with 2-3sec off then back on)
The Cycle Analyst screen is blank and there is no loading screen.

As mentioned i'll try again on an actual PC and see if this works... just wondering if anybody has ran into this issue.

 

[chilau2000]

Managed to reflash successfully on a xp laptop with same cable.
Was using a Windows 7 laptop before.

Does anyone have any tips for running v1.2 setup program on windows 7.

 

[cal3thousand]

I've searched and didn't find anything about it, but maybe Tek' will know:

Can the CA be setup to change from controller to controller on the fly? (say, using the Aux pot?) Right now, I have to go through the menus and change the values for the last 3 digits and that gets annoying.

Reason I want this function, is that my controllers are 1.333 mOhm shunted while the CA standalone shunt is 1.00 mOhm and I want to use the CA with the SA shunt for charge monitoring (dual purpose).

Options I see:

• #1 above: aux pot for quick switching (if configurable)
• #2: I've seen that someone else claim (but they didn't show how) to wire up a hack to access the controllers shunt for charging, eliminating the need for an external shunt.
• #3: Getting a 1.333 mOhm shunt into the CA SA dongle to replace the 1.00 mOhm

Any help on this is appreciated

 

[izeman]

no cal. that can't be done. shunt value is a global value. meaning it doesn't change based on profiles. i guess moving the ca from bike to bike or chaning the controller frequently just wasn't an expected usecase.
but you can program ALL values really fast with the ca programming tool. might come handy.

 

[cal3thousand]

no cal. that can't be done. shunt value is a global value. meaning it doesn't change based on profiles. i guess moving the ca from bike to bike or chaning the controller frequently just wasn't an expected usecase.
but you can program ALL values really fast with the ca programming tool. might come handy.

So, what do you think about the feasibilty of options #2 or #3?

#2 would be the cheapest, most DIY way, which I would love to know how to do.

#3 is still cool enough for school.