New "TSDZ2 Torque Sensor Central Motor"

What it really needs to do is only calibrate when you ask it to, ie from the back menu that's available. You can tell people but you can guarantee that at least once in a day they will forget to keep feet off when turning it on and you get, your battery must be gone.

Depending on the type of sensor they use, it might *have* to be calibrated every time, because some of them have a different "zero" value everytime they are powered on. (like the type used in a THUN BB sensor).

Without the calibration, then depending on sensitivity settings and how far from actual zero the "zero" starts out as, it's possible the bike could just take off on it's own simply from the difference between the last calibration of zero and the zero the sensor has at that power on.

So that is probably why it happens every power on.


What I would do is have a calibration routine that flashes the whole LCD, every icon and segment on it, to make sure to catch the rider's attention, until it's done. If there's any way to display text on there it could also say what's going on, or it could have a word-icon for "calibrating" that *doesn't* flash while the rest of the display does.

Then the actual calibration process would fault if it's out by too far (it could be pretty far off with feet on pedals), and simply keep retrying (and flashing the display) until it passes, or if the display can show text, it could say "calibrating, keep feet off pedals until done", and then display "done, ready to ride" whenever it is complete.

amberwolf said:

Depending on the type of sensor they use, it might *have* to be calibrated every time, because some of them have a different "zero" value everytime they are powered on. (like the type used in a THUN BB sensor).

Without the calibration, then depending on sensitivity settings and how far from actual zero the "zero" starts out as, it's possible the bike could just take off on it's own simply from the difference between the last calibration of zero and the zero the sensor has at that power on.

So that is probably why it happens every power on.


What I would do is have a calibration routine that flashes the whole LCD, every icon and segment on it, to make sure to catch the rider's attention, until it's done. If there's any way to display text on there it could also say what's going on, or it could have a word-icon for "calibrating" that *doesn't* flash while the rest of the display does.

Then the actual calibration process would fault if it's out by too far (it could be pretty far off with feet on pedals), and simply keep retrying (and flashing the display) until it passes, or if the display can show text, it could say "calibrating, keep feet off pedals until done", and then display "done, ready to ride" whenever it is complete.

Click to expand...

Good ideas for when we develop our own OpenSource firmware!

For the information I have now, I think it runs the motor using only 6 steps/block commutation, so should be fast to implement the motor control. The STM8 used has only 16kbytes flash memory to hold the firmware, so it can't be big and complex, should be fast to implement (the Arduinos now have about 10x more flash memory!!).

cresny said:

Creep said:

So, Tuesday evening, riding to work, I borked my nylon gear. Wednesday, I was able to replace it with one of the metal gears, and boy did I ruin that nylon sucker.

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Can you tell any difference between the nylon and metal? Smoothness maybe? I'm just wondering if there's any downside to the metal. I know I'll need a replacement sooner or later.

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I do notice a bit more noise from the metal gear at low speed (maybe 15%-20% more), but it's pretty much the same otherwise. Above maybe 15 Mph, I can't hear the motor over the sound of wind anyways. Smoothness-wise, I would say the new gear lubed with heavy grease is on-par with the nylon gear.

I was planning to buy a replacement metal gear from the get-go, as I haven't been able to find any accounts of people breaking them. Of course, strengthening one part can mean other bits take more abuse, but parts are fairly cheap and it's not a difficult motor to work on.

Given the rpm/cadence upper assist limit is a function of motor speed, is there a chance that we can change the internal gearing of the unit to move the power band?

I see there is a metal gear replacement for one of the internal gears, but perhaps there is a different ratio that might also be available?

I recently ordered a 52v 750w version of this unit but didn't realize the assist was limited to a lower cadence than would normally ride.

m3lonbr3ad said:

I recently ordered a 52v 750w version of this unit but didn't realize the assist was limited to a lower cadence than would normally ride.

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Anyone willing to donate a motor or spare parts like the motor controller (can be damaged parts), so I can investigate the motor controller and try make an OpenSource firmware and sharing public all the tecnhical details?? I hope I would be able to find more information and improve:
- see if we can customize max pedal cadence value
- see if we can change battery input voltage range (maybe cab be adjusted ony on firmware and/or on hardware by changing 1 or 2 resistors -- maybe the 36v motor controller can also work at 48v, or evn the 52v??)
- customize the motor current and assist levels (maybe we can put the same motor running at 350w or 500w, or 750w??)
- maybe we can alert user on the LCD when doing the torque sensor calibration at start-up...
- (insert your ideas here)

m3lonbr3ad said:

Given the rpm/cadence upper assist limit is a function of motor speed, is there a chance that we can change the internal gearing of the unit to move the power band?

I see there is a metal gear replacement for one of the internal gears, but perhaps there is a different ratio that might also be available?

I recently ordered a 52v 750w version of this unit but didn't realize the assist was limited to a lower cadence than would normally ride.

Click to expand...

I believe some people have been successful raising the cadence level quite a bit by replacing the 48v motor (just motor, not controller or any other part) with the 36v motor. I believe the theory is if the 48v motor runs at 90 cadence the 36v motor being fed 48v would run at about 120 cadence. I thought I read someone saying the 52v controller had (or may have) a slightly higher cadence over the 48v controller.

Newbie, looking to build on a Specialized Roll Elite comfort bike. I'm 64 and ride mostly on paved bike trails and secondary roads. I ride for both fun and exercise and don't want a throttle. I was going to buy the BBS02 until I discovered it was not torque sensing. Now I'm seriously considering this motor instead. Tons of good info here, but a bit overwhelming for me.

Questions:
I live in the US, where do you recommend I order from?
Thinking of a 48v dolphin battery for a clean install on the water bottle screws, is this a good size battery for my needs, or would a 36v be ok?
Is this motor now proven and reliable?

Farther said:

Newbie, looking to build on a Specialized Roll Elite comfort bike. I'm 64 and ride mostly on paved bike trails and secondary roads. I ride for both fun and exercise and don't want a throttle. I was going to buy the BBS02 until I discovered it was not torque sensing. Now I'm seriously considering this motor instead. Tons of good info here, but a bit overwhelming for me.

Questions:
I live in the US, where do you recommend I order from?
Thinking of a 48v dolphin battery for a clean install on the water bottle screws, is this a good size battery for my needs, or would a 36v be ok?
Is this motor now proven and reliable?

Click to expand...

When I ordered mine I could not find much available shipped from US so I ordered from PSWPower. It came out to $355 shipped for 48v motor, and the bill on the package claimed about $120 value for customs. I have not rec'd anything due for customs yet.

I have to tell you I really like the throttle. I like to ride on eco mode (lower setting) and I ride paved roads with my 25lb dog on the back. What I like about the throttle is when I get to a hill I don't have change the setting and cycle through all the pass levels to get to the correct one (it is distracting and I want to keep my eyes on the road), and even in the right pas mode it does not always give full power. With the throttle I leave it on eco mode and just give myself a boost to help get up the hill (no looking at the display, just a push of the thumb throttle and my eyes never leave the road), and I can choose exactly how much power I want. Some hills I want 100%, some hills only 75%. The throttle makes it easy to allocate exactly how much power you want for any given situation, and that helps conserve battery power too.

On flat roads it does not matter, the assist is fine and I do not use the throttle at all (unless I get tired and want a little break from pedaling).

As for battery voltage, you need to get the correct voltage for your motor. A 48v motor requires a 48v battery, a 36v motor requires a 36v battery. A 48v motor cannot use a 36v battery, and vice versa. You need to decide how many amp hours the battery has for the amount of distance you plan on riding. If you would like a recommendation on battery size you should share how many miles you plan to ride and the general topography of the route.

Some people have gotten a few thousand miles out of these motors but they are relatively new. Parts are not expensive though and they seem easy to work on. A few people have complained about some crank play (bearing issues perhaps) but some have not had any issues at all.

Anyway I hope this was helpful.

John and Cecil said:

m3lonbr3ad said:

Given the rpm/cadence upper assist limit is a function of motor speed, is there a chance that we can change the internal gearing of the unit to move the power band?

I see there is a metal gear replacement for one of the internal gears, but perhaps there is a different ratio that might also be available?

I recently ordered a 52v 750w version of this unit but didn't realize the assist was limited to a lower cadence than would normally ride.

Click to expand...

I believe some people have been successful raising the cadence level quite a bit by replacing the 48v motor (just motor, not controller or any other part) with the 36v motor. I believe the theory is if the 48v motor runs at 90 cadence the 36v motor being fed 48v would run at about 120 cadence. I thought I read someone saying the 52v controller had (or may have) a slightly higher cadence over the 48v controller.

Click to expand...

There is an earlier post suggesting the cut off for assist with the 52v version is around 130rpm based on some extrapolation. If that's the case, I should be fine with that. When I train on a normal bike, I sit around 90-100, iirc. The difference for me comes from the idea that I will be only using this motor for commuting so I can be more comfortable (less sweat), so my commuting cadence will likely be lower than training cadence (hopefully not a large difference.)

A lower cadence is not such a bad thing on Ebikes where the human body can maximise torque with max torque from the motor. Just readjust your riding style to use a lower cadence and a taller gear, it took me a while but now switch pretty comfortably from my pedal only to the TDSZ2 style.

Well, speaking of Pedal Cadence / Motor RPM... I made a little video comparing two TSDZ2 motors...

[youtube]q2efh_1ASds[/youtube]

Give it until 3s and count the rpm until 1:03s. It can be hard to tell just looking, but when you count the passes it becomes clear one is spinning faster. That being said, the standard model is spinning a bit faster than usual even - maybe just the wind on that specific motor...

58.8v on the left, which is the level of a full '52v' 14s battery, and 42v on the right, which is the level of a full '36v' battery.

For the TSDZ2, there are different motor winds used for the 36v and 48v motors. The 48v motors are actually wound 'for torque', and the 36v more 'for speed'. So the 36v and 48v standard units actually spin at the same speed. When you pair a 48v or 52v controller with the 36v motor, then you have an 'OVERDRIVE' TSDZ2. The overdrive models can get up to 120-130rpm, where the standard models are around 90-100rpm. You lose a little bit of torque - but to some - the increased rpm makes that more than worthwhile.

Did I make you watch and count? 8) I don't wanna ruin the surprise RPM total for you, plus maybe I can make you watch this video twice to count the rpm of both motors. Imagine the hits. I'm gonna be rolling in the views, I'm sure.

It would be a plus on the manufacturers part if the 52v board was available to all 48v owners. The extra speed from the unit shown is not exactly releavent to anybody who has already bought units I’m afraid, until that happens then we have a sub optimum unit.

eyebyesickle said:

Well, speaking of Pedal Cadence / Motor RPM... I made a little video comparing two TSDZ2 motors...

Click to expand...

Great work and thanks for sharing!!

eyebyesickle said:

The overdrive models can get up to 120-130rpm, where the standard models are around 90-100rpm. You lose a little bit of torque - but to some - the increased rpm makes that more than worthwhile.

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Thanks for the great post. I think it stands to reason that the extra RPMs will wear out the motor faster. But what I'm wondering is how much does it change the lifetime? I guess it's too early to know, but any thoughts?

cresny said:

eyebyesickle said:

The overdrive models can get up to 120-130rpm, where the standard models are around 90-100rpm. You lose a little bit of torque - but to some - the increased rpm makes that more than worthwhile.

Click to expand...

Thanks for the great post. I think it stands to reason that the extra RPMs will wear out the motor faster. But what I'm wondering is how much does it change the lifetime? I guess it's too early to know, but any thoughts?

Click to expand...

On the other hand, to play devil's advocate, perhaps the motor prefers the higher RPMs to spin at haha. Sounds good. But I'm assuming your speaking specifically of the gear wear?

I think it wouldn't make too much of a difference, either you are blowing out blue gears and need a metal or you're not... Most everything else (other gears, etc) is pretty reliable... Every now and then someone will break a torque sensor (I'm guessing a hard side drop onto the pedal may cause this) or the odd part will go out - but honestly, it's all pretty reliable... So I think the overdrive will be inconsequential regarding any wear factor.

casainho said:

- (insert your ideas here)

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I was out for a ride today and thought that it would be nice to be able to smooth the cut off point to conform to e-assist speed limits. I.e. If it is 15.5-16mph then one could choose to reduce assistance from 15.5mph until 17mph. That would make a far more natural transition from assistance to no assistance. Is this possible?

casainho said:

- (insert your ideas here)

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I would love it if the motor would reduce power at lower rpms when the rpms are falling fast. For instance you decide to try to climb a hill that is too steep or you are in the wrong gear and you have to stop. As rpms fall due to an event such as this so should motor output. Perhaps future motors will have grade (hill), thermal (internal engine temps), speed, cadence, torque sensors which can protect them from damage.

I would also prefer a more gradual takeoff from a stop, especially in the higher pas levels.

aja said:

casainho said:

- (insert your ideas here)

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I was out for a ride today and thought that it would be nice to be able to smooth the cut off point to conform to e-assist speed limits. I.e. If it is 15.5-16mph then one could choose to reduce assistance from 15.5mph until 17mph. That would make a far more natural transition from assistance to no assistance. Is this possible?

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Sure it is. On our current firmware, user can define the speed KI controller coeficients that will affect that!!
So, system measures wheel speed and compare with the target speed like let's say 25km/h, is up to the math that system does to cut it slower/smooth or faster/sharper.

For our help while validating/debugging all this variables, we are saving real time data of variables like torque sensor signal, PWM duty-cycle value, motor speed, wheel speed, battery current, battery regen current, etc - we send that data over Uart - Bluetooth to Android phone and analyse later on pc, here is one small ride session:

Has anyone been able to find a place that sells crank-arms with a smaller q-factor? Aliexpress?

John and Cecil said:

casainho said:

- (insert your ideas here)

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I would love it if the motor would reduce power at lower rpms when the rpms are falling fast. For instance you decide to try to climb a hill that is too steep or you are in the wrong gear and you have to stop. As rpms fall due to an event such as this so should motor output. Perhaps future motors will have grade (hill), thermal (internal engine temps), speed, cadence, torque sensors which can protect them from damage.

I would also prefer a more gradual takeoff from a stop, especially in the higher pas levels.

Click to expand...

Perhaps future motors will have grade (hill), thermal (internal engine temps), speed, cadence, torque sensors which can protect them from damage.
Thermal for motor: Kunteng motor controller has an analog input for motor temperature sensors and even cheap hub motors has that sensors.
Speed and cadence: Kunteng motor controller work with bottom bracket torque sensor (cheap one of 40€) (my 3 ebikes only have torque sensor, no cheap PAS or throttles). This torque sensor also outputs cadence and we use torque * cadence to calc human power.
Motor torque sensor: that value is the motor phase current and motor controllers already have it, on Kunteng motor controller we control that current.
Grade hill: for this cheap motors and controllers, I would had a mod of external: Arduino + MPU6050(inclinometer, etc) that would send information to motor controller over UART.

I would also prefer a more gradual takeoff from a stop, especially in the higher pas levels.

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Torque/motor current ramp would be the solution. The motor current ramp step and duration would be defined by user. Linear ramp is kind of simple to implement with simple math operations.

@casainho, I am very happy you are on board!

I don't have a TSDZ2 yet, but I do have a Bafang BBS02, and the ability to program actual power levels supplied by the motor for the various PAS levels is IMHO a very important one. For example I have mine programmed to supply 100W at the lowest setting with a slight logarithmic increase with increasing levels. I have set a very high speed limit so that means I always have a certain power level added to my own effort regardless of speed. Depending on conditions, I select the added power level; e.g. with monster headwinds I will click it up a level or 2. With my setup I don't have the feeling of riding a moped, it is still very much a bicycle, just a bit easier to ride.

So for the TSDZ2 I would like to be able to set my own assist levels for the 4 available settings. I think at present it is 33% added, 100%, 200% and 300%. I would like to be able to set those multiplication factors myself, and also the maximum power/current that these levels are working with. The default it comes on with, 33%, seems too low; I would like a useful default.

So maybe the BBS02 would work for me then? Sounds like you bought the programming cable, correct?

@casainho,

The idea of being able to teach the controller new tricks is really interesting, and could allow users to tune the system to suit their riding style and conditions.. a real bonus.
As far as the inclimometer is concerned, just remember that acceleration and braking will be read as a change in slope, which might make it more difficult to write code for that function..
Good luck with the project, I will be interested to see the results!
Dave

Farther said:

So maybe the BBS02 would work for me then? Sounds like you bought the programming cable, correct?

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Correct. For me, the original programming was close to useless and I hated it. With my own parameters it is like a different beast.