LEAFSCAN™ - The Ultimate Instrument for your LEAF!

[Ingineer]

Phil, I don't think you have answered this question yet for the non technical people out there.

What are you going to use as the bottom end of the state of charge?
Is 0% SOC going to be turtle mode (this would be my preference as reaching turtle would seem the logical 0% baseline) or is it going to be when the car shuts off and won't power back on (having dead as a baseline might encourage people to go there which doesn't seem good)?

Also, how do you (if you do) account for the variation in what the car considers 100% charge? Those with gid meters have mentioned there appears to be ~ 1% - 4% variance in the total usable energy after supposedly charging to 100%. I think it would be interesting to see if the car did or did not charge to 100%.

I'm simply reporting the Nissan battery ECU's idea of SOC. I'm not altering it, but I could add another parameter that has a more "real" 0-100% range.

Because this is starting to go off-topic, HERE is a separate thread to discuss this.

-Phil

 

[Ingineer]

Initial Capability Suggestions:

Hardware support for at least:
1. EV CAN and CAR CAN, possibly also AV CAN.
2. SDHD card slot, initially to support a full firmware update.
2a. Possibly full size SD with the future intent of supporting one of the existing "WiFi+SD" cards.
3. Display with good visibility and contrast, even in bright conditions (but not necessarily in direct sunlight). Enough resolution to provide clear-to-read screens. Color nice, but not necessary, but might be nice to provide for a nice bright cell-phone type Color Display as a future purchase option. Large enough to support characters for "old-eyes" vision.
4. Possibly support the use of the LEAF's switched 12v AND its always-on 12v (for use when charging).
4a. The "12v" is really more like 10v to 16v, right?
5. uP with at least 16 MHz, and good RAM, some EEPROM storage, and "large" flash so that these do not become constraints later.
6. Reasonable user input controls.
7. Pay close attention to operating temp range, at least about -40ºF to 160ºF so the LS will function when you get into a cold-soaked or hot-baked car.

Software Features (to make an attractive initial offering):

1. Ability to display
a. % of Usable Energy,
b. Battery A, V, W, Temp
c. Tire Pressures
d. RPM
e. Capacity: % of new, or absolute

Add Later:
a. Requested Braking,
b. Regen: % and/or absolute
c. Mechanical Braking: % and/or absolute,
d. Cell-Pair Health and Condition: Voltages and "Resistances"
e. Cell-Pair Balance: Highest and Lowest Voltages, and the Cell-Pair numbers
f. Temperatures: Cabin, Outside, Motor, Inverter, Charger
g. Pedal Position: Accelerator and Brake
h. Pump Status: Cooling (A and B), Heating
i. ... others

Features:
1. Log selected/specified Parms (what to log, and when to log it)
2. Log all CAN messages (not easy to do because the CAN Messages can come so fast).
3. Include Time Stamps in the log (I put a 2-byte ss.mmm on each log message, and inserted a date-time pseudo-message every minute).
4. Use Binary format to keep the file smaller.

This is real good thinking, Gary! Thanks for thinking about this. Most all of the stuff you asked for is already planned, and I will definitely consider anything else. The main (initial) goal is to provide the Leaf driver with the "missing" data that would be a big help to properly understand the car and make better decisions about how to get the most out of the battery while keeping in healthy. I'm sure most everyone agrees; Nissan did a fine job of creating a "everyman" car, but those of us early adopters took a "Leaf-of-faith" and we generally want to know more since EV's are still a new thing for people to live with. I've owned and even built many EV's before the Leaf, and all of them had more useful instrumentation (to me), and this is my attempt to fix that oversight.

LEAFSCAN is maybe not for everyone, but could come in handy in the future as our cars age, and especially once they are out of warranty. It could also pay for itself quickly if you found yourself stuck with a non-starting Leaf due to a trouble code (DTC) set that might be inhibiting operation. (for example a bit of dirt inside a connector) Right now there is no device that can read and reset Leaf trouble codes outside of the dealer service bay with it's $10,000 Consult III+ system.

While I would love for this to be able to do everything everyone wishes, we'll have to start small and build up. I hope to get everyone's feedback to keep making it better over time, to me that's the magic of software!

-Phil

 

[Ingineer]

Initially, there will only be support for SDSC cards (up to 4GB). There is no technical reason why future software cannot be upgraded to add support for SDHC and/or SDIO cards, so this is something that will be considered. It's unlikely LEAFSCAN will ever support SDXC, as that uses a proprietary Microsoft filesystem that demands royalty payments to use, and is also technically very complex.

Keep in mind 4GB will hold a LOT of log data!

-Phil

 

[TNleaf]

Looks great. I'll keep an eye on this thread.

 

[JohnOver]

Initial Capability Suggestions:

<SNIP>
4. Possibly support the use of the LEAF's switched 12v AND its always-on 12v (for use when charging).
4a. The "12v" is really more like 10v to 16v, right?
<SNIP>

Phil,

GargGid's comment got me thinking...

Where I work, we developed a "device" that drew ~2kW of power from a military vehicle (24V nominal). It turns out that ICE vehicles are very nasty and can have lots of excursions from nominal. There are commercial and military specs that describe the excursions. The military version is MIL-STD-1275D. I'm sure the 12V bus on an EV is much cleaner, but I thought that you would be interested in the worst-case scenarios.

I'd be happy to send you a copy Phil, if you would let me know your e-mail address (PM me). I just don't feel right about putting a link to a MILSPEC on the MNL forum.

John O

 

[copdoc]

http://www.everyspec.com" onclick="window.open(this.href);return false;
http://www.everyspec.com/MIL-STD/MIL-STD+(1100+-+1299" onclick="window.open(this.href);return false/MIL-STD-1275D_5431/

<snip>

The military version is MIL-STD-1275D.
</snip>

 

[TickTock]

I am in, of course. The features I am most interested in (in order of importance) are:

• 1) Access to all three canbus's (canbusi?) simultaneously
  2) Ability to read individual cell-pair voltages
  3) Tone proportional to brake_pressure*rpm (no tone below a certain threshold)
  • i) nice-to-have: geiger-counter style audible cue (chirps are all one frequency, but rate of chirps changes with wasted friction power)
  4) Ability to log all three canbus's
  • i) nice-to-have: Automatically log in continuous loop mode (overwriting oldest log file on sdcard) so latest log will be available as evidence in the event of accident
    ii) nice-to-have: ability to exclude certain frequent but uninteresting messages
  5) Ability to flash own firmware
  • i) nice-to-have: I know you plan to keep the firmware proprietary but perhaps providing a shell with basic canbus read/write and display subroutines would help kick-start a separate OpenSource project without exposing your "special sauce." This should improve your sales volume
  6) Ability to configure message decoding and display
  7) Ability to source user-definable messages onto a canbus (probably required for access to individual cell pair voltages and resetting DTCs)
  8) Separate user-definable display from main display (I log gids, battery voltage, etc every morning but then switch to a different mode for driving)

thought of one more nice-to-have (future update) for my list:
9) Have the display brightness change with day/night like the dash (need to figure out which canbus message indicates this)

 

[TangoKilo]

I've been immensely happy with my two EVSE upgrades. Count me in...

 

[TomT]

I believe Phil indicated that this feature is already incorporated...

9) Have the display brightness change with day/night like the dash (need to figure out which canbus message indicates this)

 

[garygid]

Sometimes an extra trace or two at initial design will provide the hardware capability to support a future-feature (like SDIO or SD&WiFi cards). But, without the circuitry in the device, no amout of future firmware would add the desired feature.

I have seen this a lot in "handheld" GPS Nav units: inexpensive ($100 to $150), great color display, touch screen, rechargeable battery, USB, an OS that can be "uncovered" ... but the lack of a "few wires" in the design kept it from being a great platform for other "projects" ... things like LS.

Sometimes, buying a mass-produced device and re-purposing it can give great value. But, often the ease of building something new overshadows the learning curve required in trying to understand something designed by others.

I have discussed a 3-CAN "SOC-Meter" board and better display, with both USB-to-VirtualCommPort real-time "logging" and SD logging, with others, but we seem to lack your understanding of the CAN data.

Please, would you tell us what you have done (or what we could do) to understand the CAN data so well?

Did you borrow/use a Consult III device?

If I can be of service in your LS effort, please let me know.

 

[jstone1]

Given that the first post states :

"...of the parameters include true SOC (with 5 digit precision!), Volts, Amps, Individual Lithium Ion battery cell parameters, battery health, temperatures, number of charges, number of QC's, indicator light history, software revision listing, motor torque/Horsepower, total kilowatts used/charged, last drive kW, last charge kW, and many more!..."

I'd say someone stumbled across a Nissan document detailing every CAN bus message, or a friendly dealer with all the diagnosis kit! Either that, or it's some amazing detective work...(which I don't doubt either given Phil's other posts!)

I take it most of this data is being pumped back to Nissan HQ data centre via telematics service, which is fine by me, but just a shame that it's not available in Carwings and/or on the more than capable nav unit to those (us!) actually using the vehicles.

 

[Ingineer]

It turns out that ICE vehicles are very nasty and can have lots of excursions from nominal. There are commercial and military specs that describe the excursions. The military version is MIL-STD-1275D. I'm sure the 12V bus on an EV is much cleaner, but I thought that you would be interested in the worst-case scenarios.

I'd be happy to send you a copy Phil, if you would let me know your e-mail address (PM me). I just don't feel right about putting a link to a MILSPEC on the MNL forum.

John O

Yes, car electrical systems are not very clean. LEAFSCAN has a power supply design to adequately deal with an cars typical electrical system, and yes, the Leaf's is cleaner than most because of the lack of an alternator, fuel pump, injectors, ignition, etc. I do not bother using the switched power pin for anything, I determine when to power up the display based on data obtained from the car.

LEAFSCAN also does automatically dim the display at night and has adjustable brightness.

-Phil

 

[Ingineer]

Sometimes an extra trace or two at initial design will provide the hardware capability to support a future-feature (like SDIO or SD&WiFi cards). But, without the circuitry in the device, no amout of future firmware would add the desired feature.

I have seen this a lot in "handheld" GPS Nav units: inexpensive ($100 to $150), great color display, touch screen, rechargeable battery, USB, an OS that can be "uncovered" ... but the lack of a "few wires" in the design kept it from being a great platform for other "projects" ... things like LS.

Sometimes, buying a mass-produced device and re-purposing it can give great value. But, often the ease of building something new overshadows the learning curve required in trying to understand something designed by others.

I have discussed a 3-CAN "SOC-Meter" board and better display, with both USB-to-VirtualCommPort real-time "logging" and SD logging, with others, but we seem to lack your understanding of the CAN data.

Please, would you tell us what you have done (or what we could do) to understand the CAN data so well?

Did you borrow/use a Consult III device?

If I can be of service in your LS effort, please let me know.

Sorry, this is off-topic. I am not going to answer off topic questions here Gary, you should know better! This forum becomes a mess in a hurry if we don't stay organized. On the LEAFSCAN: All "traces" are there for it's intended use and I'm a good enough engineer to foresee things and build my hardware accordingly. I can't absolutely promise SDIO support in the future, but the hardware will support it.

This is not a "kitchen sink" device that will cover every need for every person, but I'm going to try to make it as well as I can within the constraints needed to get it to market as soon as possible and at the most affordable price point.

-Phil

 

[davewill]

I'm willing to put a deposit down, so long as I know the final price, and have a decent idea of when to expect a unit.

 

[GaslessInSeattle]

Very cool device Phil!!

I've adapted to the tools the car came with reasonably well, I've found it's possible to get quite precise... predicting the future remains the big challenge for all of us. that said, I would still be interested in more info, the leafscan looks very cool! The battery temp alone would be worth it for me. not knowing what the battery temp is leaves charging times, range estimates/actual available charge, up in the air. Being able to target optimal battery temp for prewarming/charging before long trips would be VERY NICE!

Will the leafscan enable fresh air only to the windshield? I'm guessing not but any climate control access would be a major bonus.

maybe ClimateScan will be your next endeavor

 

[Bassman]

Count me in Phil when they're available.

 

[jkirkebo]

I do not bother using the switched power pin for anything, I determine when to power up the display based on data obtained from the car.

Nice! So this means that if I turn the car off the display will go black? And when I start charging the LS can automatically turn on the display and switch to a "charging" screen, displaying voltage, kW input, amp input, SOC, battery temperature and maybe pilot signal?

I am definately getting one :ugeek:

 

[Ingineer]

Nice! So this means that if I turn the car off the display will go black? And when I start charging the LS can automatically turn on the display and switch to a "charging" screen, displaying voltage, kW input, amp input, SOC, battery temperature and maybe pilot signal?

I am definately getting one :ugeek:

Yes, right now the LEAFSCAN goes to sleep a few seconds after you shut off the Leaf, then wakes back up when charging starts and remains on until charging stops. I'll probably make options for each mode so you can determine how it acts.

-Phil

 

[wsbca]

Due to the costs involved, we may ask for a pre-order for the initial run with a small deposit. How comfortable is everyone with that?

What about a Kickstarter campaign?

 

[garygid]

Sorry, Phil, I thought I was basically discussing LS ideas,
but I got carried away with my questions.