I was doing a review of an article someone is writing for a famous DIY bicycle website. I had to wrote a lot of things about our OpenSource firmwares and I decided to share here because it has some good details, because there are so much details that I think is difficult for some users to understand. Here are my notes:
"There are only a few companies that will sell a TS kit (Lingbei, Xofo, etc), and the TSDZ2 is not only the most available, it is also the most popular."
AND THE MOST CHEAP!!!
Like KT motor controllers, that are very cheap, like 20 euros for the cheapest controller, TSDZ2 motor is the most cheap motor, INCLUDING the all parts!! See that for instance a TSDZ2 motor controller costs only 30 euro while Bafang motor controller costs like 150 euro!!!
For me as a developer and as an user philosophy, I want parts cheap and easy to repair products, that is a question about being green/good for environment.
Temperature sensor is OpenSource firmware only
When you talk about the temperature sensor, you must first talk about the OpenSource firmware because we did develop it on our firmware as the original firmware does not support any motor temperature sensor!!
I believe that what cuts off the motor power on the original firmware, are the hall sensors because they get to hot first, since they are very near the motor coils (and the part that get's hot faster as seen on the burned motor picture). The issue is that I think the hall sensors cut at like 125 degrees and the motor will get demagnetized slowly and the motor looses torque forever but user can't see that happening....... so user will get a damaged motor without knowing why it is getting weak.
Our OpenSource firmware adds A LOT of value to this motor, I will use a list to point some features of our firmware:
I implemented FOC on our firmware (is what the implementation possible on the very resources limited STM8 chip). The result is that users do report that motor has higher torque and heir batteries has higher trip range!! -- I guess the original firmware does no implement FOC.
Feedback from experienced users:
- the TSDZ2 now feels more like the Bosch motor
- the motor is more efficient, stronger, it's feel like I have a new motor
- the bike feels very responsive and is very fast and agile whenever you need it to
- this is GOLD. I still have a smile on my face
Much better LCDs: KT-LCD3 and Bafang Color LCD
The original firmware and LCD are very limited, like they don't show to user the battery volts, motor power!! There are no way to know battery volts using original firmware which is really sad!!
As you know and think you really need to talk on the article, OpenSource firmware as also developed to KT-LCD3 and Bafang Color LCD (although this is on early development stage but I use it already on my bicycle). On this LCDs we show to user all the system information variables like battery voltage AND EVEN users can setup things like BATTERY number of cells/voltage, battery low voltage cut-off (original firmware seems to have a fixed high value so users were reporting batteries were not being fully discharged/getting max range), max current, etc.
You see, you can configure in real time the system, on the field, without any PC or such. You can simple switch batteries while riding on long trip and exchange differing batteries packs voltages, etc. I do this myself!!
Video of Bafang Color LCD, running our OpenSource firmware and TSDZ2: https://www.youtube.com/watch?v=-eZXLgWD96o
24V up to 52V battery (7S up to 14S)
Original firmware does not support 24V batteries and users are locked to use only 36, 48 or 52 volts and if they want to upgrade their batteries, they need to buy a different TSDZ2 configured to that battery.
With our firmware, users can choose to use a battery from 7 cells up to 14 cells, it can be any number on that interval!! And they can choose on the LCD, very fast and in real time.
There is at least one user using a 24V battery, because want to use very small battery and have small and light bicycle to go ride to work.
No limit to speed and higher cadence
There is no speed limit with our firmware while on original firmware is 45km/h. But yes, users can setup a speed limit, I use it for my young kid bicycle because of safety reasons.
We also implemented "off road mode", so users can remove the power and speed limits when going to trails while keep using legal limits on the street.
There is an experimental option that increases the motor cadence, as users reported that is max out at near 90 RPM. I think it can go up to about 110 RPM.
Max current and max power control on LCD
Unlike on original firmware, on our firmware users can configure the max current on LCD.
Also, we implemented max power control (yes, original firmware do not has such feature) so as battery voltage goes low, the user keeps getting the same amount of power assist from the motor! I use this a lot on trails!! instead of change assist level, I quick change to max power control mode where LCD up/down buttons increase/decrease the max power.... when I am on the trails, I do prefer to setup the amount of power motor assist me and I do it very quickly the way we implemented, as fixed predefined assist levels are no good.
We implemented a current ramp and the ramp step can be configured (not on LCD yet) and users can change the ramp step and I believe this can help to improve the life of the plastic gears, etc. Users can decide to have a very fast torque response from the motor or a lower one to improve the life of the motor parts, or maybe the battery current ramp, or for safety reasons having low torque, etc.
Battery SOC current counter
We implemented a battery SOC based on current sum. It resets automatically everytime the system starts up and the battery is charged (yes, you can setup this reset voltage value on LCD, so users can opt to charge their batteries to 4.1V as you suggest on the article!!).
Users can setup on LCD the amount of watts hour of the battery pack, meaning it is easy to swap to different batteries while for instance on a long trip.
About battery SOC, we also show the SOC based on battery voltage and user can configure the battery pack resistance on LCD, so SOC is much more stable and correct when voltage drops while riding.
Assist levels as humam power factor
We show on LCD the amount of human power the rider is doing on the pedals (in Watts, calculated using pedal torque sensor value and cadence) and it is really nice to see in real time the motor power and the rider power, so user can compare itself over time.
We also show the amount of force in Nm user does on pedals.
And also user can change to use from 1 to 9 assist levels and configure each assist level factor, all on LCD. You see, original firmware has fixed values that no one can configure...
And also very important, the assist levels are factor of rider pedal human power!! This mean you can for instance setup a factor of 1.0 and see on LCD that you are getting assistance of the motor in the same amount you are doing on the pedals.
You see, this is very flexible when we need to use TSDZ2 on an ebike for say kids, disable people or the average riders.
Because at startup cadence is zero, calculated human power is zero. Also it is good to have a boost at startup (some users do not like it so they simple disable this feature on LCD).
We implemented a power boost for startup (everytime user starts pedaling or just when ebike starts - wheel speed is 0). You can configure a specific factor of assist level during power boost (uses torque sensor signal only, meaning users still have control with the pedals. You also configure the time duration of the power boost. At the end of power boost, the power fades out linearly to the regular power/assist level and user can also configure the time duration of the fade out transition.
As you can see, we did develop advanced features that are usually present on expensive motor and big brands only. Also this features configurations are locked, only the manufacture can change them but we are users so we developed in a way we can change them, so we can take out the most possible value of this motors!!
Our OpenSource firmware is not just about the firmware itself, is also about learning and sharing knowledge about the motor and battery technology as it is strategic, for me, so we get a better world (less pollution, less cars) and more health and fit people.