Cycle Analyst V2.1 sneak preview, and call for beta testers

[justin_le]

So I'm pretty much ready to release a new version of the Cycle Analyst firmware, at least in a beta phase. The original plan was to incrementally add various new features over the year for V2.1, 2.2, 2.3 etc. but when I got into upgrading the code a couple weeks ago, well I couldn't stop myself until almost everything was done. If you've opened up a unit and seen the row of unused pads on the bottom of the circuitboard, well they can now be brought to life. The various features will be summarized in the posts to follow.

Header Pin Descriptions.jpg (66.12 KiB) Viewed 9720 times

Justin

[justin_le]

Serial Data Output

The extra small pad labeled TX is now enabled for serial data transmission, at 9600 baud, ascii formatted, tab seperated values which look like the following:

Ah V A S D
0.031 37.31 17.85 21.2 0.413
0.042 38.22 7.45 21.2 0.452
0.048 38.25 5.85 21.2 0.487

You can select whether the data rate is at 1Hz, suitable for general purpose data logging, for 5 Hz, which is fast enough to capture the dynamic response of an EV during acceleration and such, and do all kinds of vehicle performance analysis.

1 Hz Output.jpg (10.27 KiB) Viewed 8753 times

5 Hz Output.jpg (10.35 KiB) Viewed 8758 times

The output is 0-5V CMOS level, so directly compatible with other microchips, but to read it with a PC you would need an RS-232 level shifter. Fairly soon we'll be designing a plug-in circuit with a SUB-D connector on the end to allow for direct connectivity to a computer or PDA, and further down the line hope to offer an SD memory card writer, so you could ride around and all the trip data would be stored on a small memory chip.

Combined with the additional low voltage and current limiting features of the CA, this allows for some interesting possibilities. For instance, you could purchase an inexpensive bicycle trainer stand and use it as a stationary load for your ebike, then completely discharge the battery pack at constant current by running the hub motor on the stand, with the CA recording the discharge profile on a PC and maintaining the constant current discharge. No need for massive load banks, and you can test up to 100V or 200V battery packs without even removing them from the vehicle.

[justin_le]

The additional pad labelled 'Vi' is an auxiliary voltage input. This input can be configured to scale either the speed limit or the current limit, from 0 up to the max value that has been programmed into the CA.

Aux Off.jpg (8.79 KiB) Viewed 8728 times

Aux Amps.jpg (8.76 KiB) Viewed 8714 times

Aux Speed.jpg (8.9 KiB) Viewed 8697 times

One obvious use for this is to use to wire a potentiometer to the pad, and have a knob for simple adjustment of the speed or current limit, so that you don't have to enter the setup menu and go through all the button pressing just to change it.

Aux Pot.jpg (39.41 KiB) Viewed 8704 times

Another application would be for the rider to actually use this as a kind of 'throttle interceptor'. The user's throttle goes to the CA, then the Cycle Analyst takes this as a desired speed or current that the user wants. The CA sends its own signal to the motor controller via the 'Th' pad in order to achieve that speed or current. So instantly your throttle becomes a cruise control, or a power control, for the vehicle. In expectation of this use, the Vi input range is default to 1-4V, allowing for taking the signal directly from hall effect throttles, although that range can be tweaked.

Aux Thresh.jpg (8.28 KiB) Viewed 8688 times

[justin_le]

In addition to the above things, there were some upgrades to the base code base as well:

Presetting the Odometer and Lifetime Ahr Accumulator

It is now possible to preload the life-cycle values into the unit, so people replacing original bicycle computers or similar devices can transfer that information over to their Cycle Analyst.

Odometer Preset.jpg (9.93 KiB) Viewed 8663 times

Increased Ah and Distance Ranges

The amp-hour, watt-hour, and distance accumulators have all been increased by a factor of 10. So in a given trip you can go up to 1,999 km or miles, draw up to 1999 amp-hours from the battery, or use 19,999 watt-hours of power. In high range mode, both the Ah and Wh are increased by yet another factor of 10, so 20,000 Ah and 200,000 Wh.

Support up to 99 Poles

The maximum number of poles has been increased from 14 all the way to 99 , since a lot of the newer hub motors seem to have upped the number of magnets substantially.

99 Poles.jpg (8.87 KiB) Viewed 8646 times

[Mathurin]

Built in current throttle, nice!

[justin_le]

I'm looking for people who want to be beta testers, and who are very explicitly interested in trying out and using either the data logging or on-the-fly speed/current limiting features above. If this is you and you already have a Cycle Analyst, then that can simply be shipped back here and I will reprogram it for free. Alternately, I have made up a small number of units having large display screens with enclosures and waterproof tactile switch button and all. These are in-development prototypes for a larger EV sized meter, not something that will become production ready for many more months, but I have exactly 8 units made up that I'll offer for the same rate of $150 with the V2.1 Beta code.

Large Format CA.jpg (26.89 KiB) Viewed 8607 times

In either case, if you want to be a beta tester then send an email with "Cycle Analyst 2.1 Beta" or similar in the subject to sales@ebikes.ca, with a bit of background on yourself and your project, and a brief explanation of how exactly you plan to make use of these features. If there are general questions of any kind, please post them to this forum and I'll try to respond promptly.

Justin

[deecanio]

Hi Justin,

im not going to pretend i have the knowledge to really appreciate all those extra features but i bet the guys will be totally stoked with all the work you have done on the CA.
For myself i'd just like to say well done and thanks for all your effort in making such a great piece of kit!!!!
I'm still happy with my DB but i will be getting CA when i upgrade my packs - again thanks for all the effort in getting us such a wonderful gizmo!!


Cheers


D

[drewjet]

Very Nice!

I sent you an email.

[Ypedal]

Great Work J !

It's great to see a product evolve on a yearly basis !

Keep it up !

[Jozzer]

Aye, fantastic work Justin. I'm keen to try one too....any chance of a motorbike sized one for my aprilia?

[Drunkskunk]

Data logging is what I need right about now, and the speed feature would realy help as well.

had you considered being able to store several speed and current profiles in the CA? I've found many instances where it would be nice to be able to change both on the fly, then change them back only minutes later. I.E., uneexpectedly finding myself on a road with faster traffic, or trying to get up a hill that's steeper than I had planned, Or, sudden opportunity to race a Lycra rider.

[Ypedal]

Yeah.. a " Lycra Mode " button ! swweeeeeet..

[fechter]

Excellent!
Now I don't have to build my own from scratch. On-the-fly current limit adjusting is a nice feature.
Will it be possible to adjust the maximum current limit with a pot and use the current feedback throttle at the same time?

[justin_le]

Excellent!
Now I don't have to build my own from scratch. On-the-fly current limit adjusting is a nice feature.
Will it be possible to adjust the maximum current limit with a pot and use the current feedback throttle at the same time?

Well Fechter, I think you have enough circuit trickery up your sleeve to figure this one out. One easy way that pops in my mind would be for your throttle output to drive the positive side of the potentiometer instead of fixing it at +5V.

Justin

[justin_le]

Data logging is what I need right about now, and the speed feature would realy help as well.

had you considered being able to store several speed and current profiles in the CA? I've found many instances where it would be nice to be able to change both on the fly, then change them back only minutes later. I.E., uneexpectedly finding myself on a road with faster traffic, or trying to get up a hill that's steeper than I had planned, Or, sudden opportunity to race a Lycra rider.

The idea of the potentiometer was to allow that instant change of one of these factors, but obviously it can't do both the speed and the current limits at the same time. And there isn't another spare input pin for a 2nd pot. However, one really easy way to achieve a similar effect with the flip of a button is to install a switch in series with the green throttle over-ride line. Once you flip that, then the CA limiting features are shut off and you get full power up to what the controller will allow. The pics below show an example of this:

Throttle Toggle.jpg (27.73 KiB) Viewed 8460 times

Throttle Toggle, Closed.jpg (17.55 KiB) Viewed 8452 times