[SOLD OUT] Brain Box - New ebike computer/throttle

[adrian_sm]

Update:

Thanks for everyone's patience. The holidays didn't leave any much time to make kits, and I have had to convert my garage into an office workshop to give me the space this little project needs. Unfortunately this means I won't have the workshop functional for a few more days yet. The good news is that I have the CBs 90% made, enough parts for the Brain Box's, and my family is interstate for a week more so no distractions.

Again sorry for the delay, but I really need to make a dedicated space to work on the Commuter Booster to make production more efficient. I hope you all understand.

Regards,
Adrian

[marty]

It's great to see a fuel guage type function in there. It's something I've been hoping Justin will do. Especially when building bikes for folks who are not familiar with ebikes, its much easier for someone to understand the total %, rather than having to compare watt-hour figures. Very cool

AGREE!

[adrian_sm]

Update:

Final testing and manufacture of the Brain Boxes has gone far from smoothly.

Manufacture has been a lot more labour intensive than I envisaged. So I will not be offering a fully featured brain box again at this price level.
After more exhaustive testing I have identified an intermittent issue with the firmware that is unacceptable. This stems from hitting the memory limits of the uController. I have spent a great deal of time trying to optimise the code while keeping all the features, but have failed, and don't want to delay release of these any further.

So unfortunately I am planning to drop the microSD datalogging feature. This feature had proved essential during development in understanding the inner works of the commuter booster, which made me believe that it was a feature that will be used a lot by others. But now that I have the system optimised, it just doesn't get used. And this features alone takes up nearly half of the memory space of the uC. Which greatly restricts what additional features and optimisation I can add at a later date. Like:
- analog throttle
- adjustable torque limits
- PAS (Pedal Assist Sensor)
- etc.

The other feature that was useful during development but became a pain was the temperature sensor. For people to make use of it they need to install a temperature probe (that is quite cheap and readily available) in good thermal contact with the motor windings. So requires cracking open the motor, getting some good thermal epoxy, finding a nice home for the sensor, setting it in place, routing the wire safely out of the motor, and ensuring it doesn't foul on anything, then weather proofing the cable back to the brain box. Given this level of effort, I only did it during development on a few motors as I tested their relative merit, but since then I just can't be bothered. And running the motor at 500-1000w, I just don't have over heating issues. It is even less attractive if we don't have the data logging. As you can't track the instantaneous thermal response for that one killer hill etc.

I believe these are two features that 95% of people just don't need, and won't be missed, and it will definitely make for a more robust and expandable unit looking ahead. In the future if I manage to optimise the code, and reintroduce these, it is will be possible for people to upgrade their units by simply soldering in an extra half dozen wires, drilling a hole, and flashing the new code.

So....... what is the response from people if I drop these two features?

- Adrian

P.S. Oh and here are a few pics of the new workshop (which has made it sooooo much easier to get work done), a few BB in the making, and the CB & BB most people are ordering.

[adrian_sm]

Brain Box Size.

I just wanted to highlight how compact the Brain Box is, so here is a quick pic next to a Cycle Analyst. Personally I find the CA-LRC screen size a bit too big for a bike as it dominates the handlebars, but I know some people like the BIG characters. Each to there own.

- Adrian

[Grinhill]

No problem for me if the logging and temp sensor is dropped, Adrian. I would be using it for a simple-to-use jump on and ride setup for my wife.

I can do logging in other ways if necessary, and like you say, after you've got a system sorted, you rarely need to go into that much detail for day to day riding.

[adrian_sm]

Okay everyone via email, PM and here so far are happy to drop the datalogging for now, and I have had a single request to keep temp sensor. This will allow us to free up a lot of memory space, eliminate the issue that has been holding up release, and allow lots of room for future upgrades.

I will likely keep the temp sensor as an optional extra. The main issue is later on as we modify and upgrade the firmware with feedback from all the Alpha testers, it gets increasingly difficult to keep maintain multiple versions of firmware. I am anticipating that the Alpha testers will take the time to suggest changes or additional features, that I will implement then release firmware upgrades. This is simply a process of plugging in the usb cable, and running a simple program on your MAC/PC.

The sort of change requests I am anticipating are:
- display screen layouts changes
- menu structure changes
- different default display
- ability to save personal settings (similar to factory defaults settings that can be used to reset the unit)
- additional features like:
--- analog throttle
--- user adjustable torque limit (based on power & speed, to reduce wear/slippage in non-ideal environments)
--- external pot for on the fly adjustment of power limit, torque limit, speed limit, whatever. Actually thinking about this when I implement a twist throttle input, we should be able to use that analog input and the digital button input to do the adjustment in a pretty slick manner, without the need for another analog input.

Basically I would like people to take the opportunity to get the product they really want designed. If there is a feature they really want, or something they want changed/tweaked/optimised to their liking, this is the chance to influence it.

In Summary
Anyway, unless I get a flood of messages requiring , I am going to finish of these units without the datalogging and temp sensor as an optional extra available by request. This will finally get the units in peoples hands, and on their bikes.

Thanks again for all you understanding and patience.

Regards, Adrian

[guttomek]

I didnt get my CB and BB yet but I believe that "user adjustable torque limit (based on power & speed, to reduce wear/slippage in non-ideal environments)" would be my pick from the list of your ideas.

[renaatdb]

Adrian,
No problem for me if the logging and temp sensor is dropped, Adrian

Thanks

[adrian_sm]

Quick pic of a batch of Commuter Boosters, and a bucket full of Brain Boxes ready to ship.

fr_966_size640.jpg (141.24 KiB) Viewed 1102 times

[adrian_sm]

New manuals are currently being uploaded to the website. Sorry about the huge file sizes, I couldn't be bothered working out how to compress them. The manuals are still not perfect, but should be good enough for most of you.

- Adrian

[adrian_sm]

Update:

Now that a fair few of these are out in the wild, we have only had a couple of issues so far. But I thought it was fair to share. So here is what has happened.

1) Packaging
- one unit was damaged in transport. So I have started boxing them up more securely now.

2) Corrupt Screen
- two units now have had the screen get confused and display random characters
- this was due to poorly solder connections, and solved by resoldering the display wires on the main microcontroller board. A 2 minute job with a soldering iron, but unacceptable none the less. So we have improved the QC inspection to resolve this.

- Adrian

[Grinhill]

One minor tweak I had to do out of the box was adjust "tMin" a bit lower in order to get my ESC to arm.

I'm using the same 85A ESC as yours Adrian, but it would only arm when I lowered the value from 1100 to 1000.

Otherwise, working really well, simple to install and simple to program.

Thanks!

[deVries]

- screen uses standard HD44780 interface, and code design to allow easy expansion to different screen sizes. So a 16x2 screen is electronically a relatively simple upgrade in the future if people require more screen realestate. Or 20x4 for that matter.

My reading vision is not what it once was. Can you tell us how to compute the meaning of 20x4, for example, in order to understand that as an actual measurement size? Best place to get the upgraded screens for the USA?

- If I ever plan to permenently stop developement, I plan to make all source code public, so others can implement any changes they require in the future.

This is fantastic, not that I know how to code this, but someone could contribute I'm sure. Thank you Adrian!

Planned future developements:
- analog throttle input/output to suit hall/pot throttles, and normal ebike controllers.

Any WAG or ETA for this option?

Price:
- AU$140 + shipping
- unfortunately these are quite time consuming to assemble, but it is still cheaper that a CA and Analogger.
- If you are not interested in the datalogging or temperature sensor, I can probably drop the price down a bit, let me know.

I think these come w/o the datalogging & temp sensor now at $140 or ?, correct?

Are these still available now? Cost for datalogging & temp sensor is? What options will be sacrificed to add these two options?

Folks, Adrian, is one of the most detailed & clear posters with *awesome* development & electronic skills I have ever found on ES.

Guys, you can not go wrong dealing with Adrian, imo. He has been stellar in responding to questions by PM too, so I can guarantee you he has put in the time and sweat equity to make something great now & even better in the future. Honestly, this is the best product development I've seen on ES along with his FD. He is carefully developing this with amazing patience over the long-term. I will be buying & recommending his products, when I can.

I AM VERY IMPRESSED, Adrian!

Adrian gets my highest 5 Star Rating, which I can not rate higher.

(Though, I'm embarrassed to admit I have not already bought his brain box or FD yet, but I will be doing that for sure in the near-term & provide feedback.)

[adrian_sm]

One minor tweak I had to do out of the box was adjust "tMin" a bit lower in order to get my ESC to arm.

I'm using the same 85A ESC as yours Adrian, but it would only arm when I lowered the value from 1100 to 1000.

Otherwise, working really well, simple to install and simple to program.

Thanks!

Yes. Confirmed. I will drop the default tMin to 1000 in the future.

[adrian_sm]

- screen uses standard HD44780 interface, and code design to allow easy expansion to different screen sizes. So a 16x2 screen is electronically a relatively simple upgrade in the future if people require more screen realestate. Or 20x4 for that matter.

My reading vision is not what it once was. Can you tell us how to compute the meaning of 20x4, for example, in order to understand that as an actual measurement size? Best place to get the upgraded screens for the USA?

ebay is as good as anything. Just search for HD44780.
20x4 refers to the number of characters wide and high. so 20x4 is 20 characters wide, 4 high.
http://www.ebay.com.au/sch/i.html?_from ... Categories

But if you need a big screen, just go for the Cycle Analyst. The main reason I developed my brain box was I wanted a small inconspicuous screen, and the CA didn't have some features I needed. But now the new v3 CA has nearly all the features of the brain box, and is a product with a lot more history, production volume etc, so you are likely to have a more robust product.

So there is not much point me making a big screen brain box. This means I will focus on small-screen and no screen throttle interfaces.

Planned future developements:
- analog throttle input/output to suit hall/pot throttles, and normal ebike controllers.

Any WAG or ETA for this option?

Soon. I have just had to set up a company to take care of this project, so that has taken a bit of my time recently, as well as keeping up with orders. Once I ship out the last few outstanding orders, I will stop the current release manaufacturing, and focus on the R&D of the next variant.

High on the list is:
- analog throttle
- basic model BB without display, with PC-USB programming, possibly with common firmware with the display varient. So I don't have to maintain two varients.
- electronic torque limit, for controlling maximum torque (mainly at low speeds), while still allow higher power at higher speeds.

ETA: Let's say a month or so.

Price:
- AU$140 + shipping
- unfortunately these are quite time consuming to assemble, but it is still cheaper that a CA and Analogger.
- If you are not interested in the datalogging or temperature sensor, I can probably drop the price down a bit, let me know.

I think these come w/o the datalogging & temp sensor now at $140 or ?, correct?

Are these still available now? Cost for datalogging & temp sensor is? What options will be sacrificed to add these two options?

No datalogging for now. It is a cool feature that I used a lot during developement, but most people really don't need it.
Temp sensor is simple and may make a reappearance, but again once setup you never end up using it apart from the nerdy I must know more stats aspect. Those seeking to really push the limits in terms of power just shouldn't be using friction drives, and the brain box is really design for my friction drive first.

Price is $140. No datalogging, no temp sensor. I really should update the first post.

But there will only be a few more sold, before I shut shop for a while. This will let me get feedback from all the Alpha testers, and fix everything up for the next version.

- Adrian

[deVries]

High on the list is:
- analog throttle
- electronic torque limit, for controlling maximum torque (mainly at low speeds), while still allow higher power at higher speeds.

ETA: Let's say a month or so.

These are just firmware upgrades, so existing models can be upgraded for the above 2 features? Correct

No datalogging for now. It is a cool feature that I used a lot during developement, but most people really don't need it.
Temp sensor is simple and may make a reappearance, but again once setup you never end up using it apart from the nerdy I must know more stats aspect. Those seeking to really push the limits in terms of power just shouldn't be using friction drives, and the brain box is really design for my friction drive first.

This is exactly why your data logger & temp sensor may be more useful for the DIY crowd. Why? Your device can be used for other setups besides FD. For example, Thud's RC Reduction or Matt's Offerings or just our own DIY experimenting with more than one motor or multiple builds. You know you can't just have one or two eBikes.

[adrian_sm]

High on the list is:
- analog throttle
- electronic torque limit, for controlling maximum torque (mainly at low speeds), while still allow higher power at higher speeds.

ETA: Let's say a month or so.

These are just firmware upgrades, so existing models can be upgraded for the above 2 features? Correct

Yes firmware upgrades, plus wiring in any new IOs. So anybody with an alpha unit and a soldering iron can join the fun.

As for the datalogging, I dropped it because I hit a memory space limit. Yes it is possible. Yes I know some people want it. Yes it is what a lot of people on ES will want/need. But I won't be offering it. The DIY/ES market is not my target market, and I hit the memory limits which was restricting me implement more important features.

If you are that keen here are the posts that will give you all the hardware required, and the links to the code resources to get you started on rolling your own. Just buy an arduino of you choice, I recommend the Arduino Nano, and read these...

Voltage & Current Sensor, and Throttle Signals
viewtopic.php?f=2&t=29561&hilit=arduino+microsd#p427859
Wheel sensor code
viewtopic.php?f=2&t=29561&hilit=arduino+microsd#p427861
PID, LCD & SD hardware and code links
viewtopic.php?f=2&t=29561&hilit=arduino+microsd&start=15#p447908

Have fun, Adrian.

[deVries]

High on the list is:
- analog throttle
- electronic torque limit, for controlling maximum torque (mainly at low speeds), while still allow higher power at higher speeds.

ETA: Let's say a month or so.

These are just firmware upgrades, so existing models can be upgraded for the above 2 features? Correct

Yes firmware upgrades, plus wiring in any new IOs. So anybody with an alpha unit and a soldering iron can join the fun.

As for the datalogging, I dropped it because I hit a memory space limit. Yes it is possible. Yes I know some people want it. Yes it is what a lot of people on ES will want/need. But I won't be offering it. The DIY/ES market is not my target market, and I hit the memory limits which was restricting me implement more important features.

If you are that keen here are the posts that will give you all the hardware required, and the links to the code resources to get you started on rolling your own. Just buy an arduino of you choice, I recommend the Arduino Nano, and read these...

Thanks for the references, but I don't have the programming experience/skills to do this.

If I get a larger screen size would it be best just to put it in a 2nd box for the display only and use your original box for the other components, or should I gut your box & move it all into a bigger unit to fit the large screen too? How would you recommend to do this screen upgrade using your brain box?

Thanks!

[adrian_sm]

You wouldn't be able to do a screen upgrade without new firmware to support the bigger screen size.

Again all technically possible, but not something I am interested in offering. I am selling this units pretty much at cost, and can't afford the developement time to do one offs for people. Sorry.

Just go with the Cycle Analyst. It has the big screen, analog throttle input, and is ready to rock.

- Adrian

[adrian_sm]

Cross-post: http://www.endless-sphere.com/forums/vi ... 75#p578180

PUBLIC SERVICE ANNOUNCEMENT - TURN OFF THE ESC WHEN YOU FINISH YOUR RIDE

I have just had an email from someone that rode their bike to the ESCs LVC. This cut the power and stopped him from damaging his battery, all good. But .... unfortunately he did not then turn the ESC off. The ESCs typically draw 1.0 - 1.5w when on, and the brain box another ~0.3w. So this will slowly drain your batteries when on. Anyway, the next day most cells in his pack were @ 2.5v, but one on each pack was at 0.5v.

This was all on a 5s10Ah pack, so ~185wh.

As an example let's see what leaving the ESC on for a day would do.
1.8w x 24 hours = 43 wh
That is roughly a quarter of the packs capacity.

So please remember to turn off the ESC, or unplug the battery when you have finished your ride.

- Adrian

So any ideas on what we could do to protect people from this, while not being annoying.
The system has at it's disposal:
- an ESC on/off switch
- a pack voltage sensor
- a programmable micro-controller with spare inputs and outputs
- knowledge of throttle input states and time

I previously implemented an LVC in the Brain Box, but only had it restricting throttle out. So it would either trip under voltage sag early, or be set at a point lower when the ESCs LVC would have already cut the power. Making it pretty useless.

Perhaps we could instead have a relay on the on/of switch which turns the ESC off if the voltage drops low, and/or the throttle input has been off for a long period of time (say 1 hour). I just can't quite get my head around how to power the relay, and reset it.

Would this work?
- A push button NO button in parallel to a NO relay.
- Pushing the button turns on the ESC and powers the uC.
- the uC then turns on the relay, keeping the ESC switch on, and therefore powering the uC which keeps the relay closed
- then if the LVC hits and/or throttle off for too long then relay turns off and opens, turning off the ESC & shutting down the uC
- then the user would have to press the button again to power things up.

[methods]

I have not read this thread - but was invited to comment via PM.

I have one quick comment to make
There are many clever things we can do with the logic - that part I am sure will work out. The troublesome part is the component used to break the power to the ESC. DC voltage is a bugger in that it does not want to break easily. This is why we see tons of relays and breakers on the market for 120V 20A AC but anything for DC is usually limited to 12V 40A. As voltage goes up the ability of a relay to break the current falls off exponentially. At higher voltages (and with a good current running) when the relay opens the DC can easily arch a centimeter or two. This results in major damage to the relay contacts, failure to open the circuit, welding of contacts, and a bunch of other nasty stuff.

For this reason - any time we want to break DC we have to either use a high end contactor (large, heavy, expensive, requires large bias current to hold closed, ...) or we have to build a sold state switch. Before anyone gets excited... no you cant use the $20 SCR's available on Ebay Those are only good for AC. We have to use a Mosfet switch. There are two main problems with these: 1) they are unidirectional in their ability to break current (body diode bypass - which opens up a whole different can of worms) and 2) they create heat, have voltage and current limitations, and require biasing circuitry

So yea...

I build a cell level HVC breaker for my Battery Protection system that works by employing 4pcs of IRFB4110. Those have 4mohm internal resistance, so 4 of those in parallel results in 1mohm inline. That means that heat will be produced with the current squared... so

20A ^ 2 * 1mOhm = 400mW
40A ^ 2 * 1mOhm = 1.6W
60A ^ 2 * 1mOhm = 3.6W
80A ^ 2 * 1mOhm = 6.4W

So as you can see the burden climbs quickly... 6.4W is a TON of heat to try and shrug off with an inch or two of aluminum... heat jumps to 60C or 80C in just a few moments. So - I guess without getting into this what I am saying is that it does not scale well and requires circuitry AND thermal management.

Lately I have spent a lot of time via PM explaining my philosophy on this... and my hands are getting tired now but long story short I think the best VALUE (that is bang for the buck) is to have our systems cut throttle and rely on users to remember to turn off their ESC.

As a final note... When thinking about leaving a bike sitting with the ESC on you should visualize leaving your car in the driveway idling and going to bed. It is absurd to think we would leave our car in the driveway idling - we have taught ourselves to never do this. Well... those of us who daily drive EV's quickly learn to never leave them on. It may happen from time to time... but it is basically something that just has to be learned. It is too expensive and complicated to try and manage it.

-methods

[adrian_sm]

Thanks methods.

The concept I outlined above is not breaking the main battery DC, but just the controllers existing on/off switch that provides power to the uC, drawing ~40mA on the controller I am using. This in my mind is the main selling point as I imagine that it would allow reliable switching with affordable parts.

What do you think?

Here is a reference pic of the type of controller (top ESC), with the existing switch I would like to replace with a relay or something.
Note: the little switch on the end of the thin wires that is the on/off switch I am proposing to modify.

http://www.hobbyking.com/hobbyking/stor ... duct=10331

- Adrian

[adrian_sm]

BTW. My DMM measures no battery current when the on/off switch is off for this little RC ESC. But from memory my XieCheng controller has a bleed resistor on the main power caps that still slowly drains the battery when the power switch is off.

[EDIT] Here is the schematic for a 116 XieCheng 6fet controller. It too has an on/off switch. Opening this cuts the power to the LM317, and powers down the uC, but it still leaves the bleed resistor I mentioned across the pack voltage (R203 on page 3).

[vvougiatzis]

Another simple idea that would have probably reminded me to turn the switch off would be to have the brainbox LCD backlight constantly on. When I left the bike with the switch on it was dark and I would probably have noticed the light from the screen. I understand this will not work so well in daylight and it will draw more current but in many situations it would be a saver.

[adrian_sm]

This is a simple mod if you are up for it, p21 of the manual.

But does use ~0.3w of extra power.