BuWizz - High Performance LEGO Power Functions Controller and Battery

[amorti]

17 minutes ago, Zerobricks said:

You can tune centering parameters in the center steering module, I would increase the deadbandout boost to help overcome the sticktion. You have to play around a bit with the settings sometimes. 

At max deadband boost, it's the same.

[Jundis]

5 hours ago, Zerobricks said:

The number of gears/positions is automatically calculated according to the end limits. If end limits are around 90 degrees, than 2 gears, 180 degrees 3 gears and 270 degrees 4 gears. The angle is 90 degrees, since the gearbox module is  designed to work with a wave selector.

Hmm ok, then the module won't work for my gearbox, as it is connected to a wormgear and a 20:12, meaning 1080° for EACH of the four gears :-/

Edit: Could you implement a selector for "Individual Gearbox", where the steps (in °) and the number of gears can be selected individually?

Edited April 8, 2023 by Jundis

[Krxlion]

5 hours ago, amorti said:

I was trying too early, nothing had updated. First time beta testing!

Of course I know in theory how to put end stops and set up a motor as a servo.

That is good to know about the reduction.

But it doesn't work. The servo just makes a light whistling sound when I tell it to calibrate, it doesn't move towards the end stops at all.

Annoying I can't readily video it with the same phone doing the calibration :/

Same thing, but I am using C+ L motor, which serve as a servo-motor. Something is seriously off, I believe that any C+ motor with center steering module will not work. I wanted to test current limits but I cannot do so If my steering is not working properly. I switched back to Brick Controller app with PS4 pad, everything works corretly.

[Zerobricks]

5 hours ago, Danil said:

On the 2nd port, one latch is broken, on the 3rd port, both.

As mentioned, please send a ticket and I will see what we can do.

5 hours ago, amorti said:

At max deadband boost, it's the same.

As with fine tuning anything, I suggest you take some time, see the parameter description and change them one by one until you get a result you want. That's how I do it too for my models too, it takes patience.

1 hour ago, Jundis said:

Hmm ok, then the module won't work for my gearbox, as it is connected to a wormgear and a 20:12, meaning 1080° for EACH of the four gears :-/

Edit: Could you implement a selector for "Individual Gearbox", where the steps (in °) and the number of gears can be selected individually?

The Gearbox module was designed for models like the 42114 and 42131 where the motor drives the wave selector more or less directly. Your case is much more specific, with enough requests we might look into it too.

1 hour ago, Krxlion said:

Same thing, but I am using C+ L motor, which serve as a servo-motor. Something is seriously off, I believe that any C+ motor with center steering module will not work. I wanted to test current limits but I cannot do so If my steering is not working properly. I switched back to Brick Controller app with PS4 pad, everything works corretly.

Try creating a brand new profile from scratch. Also remember to use enough centering calibration power.

[amorti]

7 minutes ago, Zerobricks said:

As with fine tuning anything, I suggest you take some time, see the parameter description and change them one by one until you get a result you want. That's how I do it too for my models too, it takes patience.

I understand what you're saying, but I cannot agree. This is a toy. I didn't pay 250€ for a battery and two motors expecting to be referred to a 48 page user guide and have to program the thing every time just to have it work.

So, I've reverted my latest model to a Chinese battery and PF servo. It won't be as fast, it won't be as fancy, but it will have some 200€ less money in it, and it'll work every time without programming further than deciding whether to couple or reverse any of the PF ports.

Edited April 8, 2023 by amorti

[Zerobricks]

17 minutes ago, amorti said:

I understand what you're saying, but I cannot agree. This is a toy. I didn't pay 250€ for a battery and two motors expecting to be referred to a 48 page user guide and have to program the thing every time just to have it work.

So, I've reverted my latest model to a Chinese battery and PF servo. It won't be as fast, it won't be as fancy, but it will have some 200€ less money in it, and it'll work every time without programming further than deciding whether to couple or reverse any of the PF ports.

I understand your just want to plug in and play. But on the other hand we also have people asking for more complex functionality and programming options like the gearbox module going 1000+ degrees for each gear above. Can't and never will be able to please everyone, no matter how much I try.

[aFrInaTi0n]

Zero, I think nobody is mad at you personally, more like at the vendor Buwizz I reckon.

I would hope for at least some good default values for the different PWM motors setups possible with Buwizz.. like "for the angular thingies, this and that needs to be set to x, y, z". Do they have the angulars available at Buwizz HQ for further testing?

 

[gyenesvi]

6 hours ago, Danil said:

Hello! while designing, the child broke the latches on the PU ports, and now the motor plugs are falling out - can these elements be replaced or purchased? thanks in advance for advice.

6 hours ago, Zerobricks said:

First time hearing about such issue. Your child broke all latches on all ports? The connectors are soldered to the PCB at 6 points, so replacing them is not easy... I think this question is better to be posted on support mail. 

Hmm, same thing happened to me (no child involved), and I think I reported that too. On my Buwizz 3 unit I bought in the camp last year, the first time I inserted a motor plug, one side of a latch broke immediately. Soon the other side broke as well. After a bit of usage, it happened to another port as well. Luckily, the plug has enough friction to stay in there just by itself, so I gave up on fixing it.

6 hours ago, 2GodBDGlory said:

It might not be the best solution, but if I'm picturing the situation correctly, I'd probably just try supergluing it back in place

It's like a 1x2mm piece and it's on the inside of the plug hole, inaccessible :)

[Zerobricks]

3 minutes ago, aFrInaTi0n said:

Zero, I think nobody is mad at you personally, more like at the vendor Buwizz I reckon.

I would hope for at least some good default values for the different PWM motors setups possible with Buwizz.. like "for the angular thingies, this and that needs to be set to x, y, z". Do they have the angulars available at Buwizz HQ for further testing?

 

I know, no worries

As for your question I'm the only person doing such tests and it's not so simple, since each use case is very different. That is why I made the 3 default center steering presets.

For example a PU XL motor has very low internal friction and needs much less power to turn than the medium angular motor.

Also the way the motors are used in the models matters a lot:

• Are they using a direct gearing to the gear rack or is there additional gearing down?
• What size is the gear controlling the steering rack?
• How long are the steering arms, since they act as levers?
• What's the weight of the model, the more weight, the higher force you need?
• What's the weight of the wheel and their intertia so that the system doesn't fall into the a positive feedback loop and starts oscilating?

 

Even if we look at the official 42114 model it had problems with the steering oscilating and that model's profile was fine tunded to that very model.

 

[amorti]

21 minutes ago, Zerobricks said:

we also have people asking for more complex functionality and programming options like the gearbox module going 1000+ degrees for each gear

Your focus absolutely should be making it work for simple functions, straight out the box. It doesn't make any sense to even consider a 3-rotation gearbox module which one user wants, while servos aren't calibrating and centering properly which every user wants.

Does the buwizz know from the motor, which motor it is ?

A lot of the variables you mention can be eliminated by making it a requirement to pick the model up before trying to calibrate the steering.

 

[2GodBDGlory]

22 minutes ago, gyenesvi said:

It's like a 1x2mm piece and it's on the inside of the plug hole, inaccessible :)

Oh, I was thinking to glue the whole plug in place, making the clips irrelevant.

[gyenesvi]

1 hour ago, amorti said:

I understand what you're saying, but I cannot agree. This is a toy. I didn't pay 250€ for a battery and two motors expecting to be referred to a 48 page user guide and have to program the thing every time just to have it work.

I think @amorti does have a point here, I'm not satisfied with all those parameters either. From my research/engineering background I know how such scenarios come to existence: the engineers cannot design an algorithm that works reliably for all cases, so they come come up with a parameterizable solution, and allow the users to adjust the parameters. Now some parameters are okay, the problem is when the parameters are too many and hard to interpret. One typical case is when it is not entirely clear what a parameter effects or what its range is. A motor speed/power is easy to understand and set between 0 and 100%. But parameters of a PID controller are not intuitive and their ranges are not well defined (open ended), so putting those into the hards of everyday users is kind of questionable. I would personally prefer if the user could only set simple things like steering power and steering speed that they can easily understand and tune, and the firmware would derive its internal parameters from those. The lego firmware only uses such parameters and they manage with it. For example the user tells the FW by steering speed how responsive steering it wants, and all related parameters can depend on that. Also, by setting steering power, the user basically gives info on how heavy the mode is or how the steering gearing/linkage is, and all related internal parameters could depend on that. Did the team try such approach yet?

2 minutes ago, 2GodBDGlory said:

Oh, I was thinking to glue the whole plug in place, making the clips irrelevant.

You mean glue the motor plug into the Buwizz unit? That's like glueing your model together.. :) Not really a reusable solution..

[Jundis]

6 minutes ago, 2GodBDGlory said:

glue the whole plug in place

4 minutes ago, gyenesvi said:

But parameters of a PID controller are not intuitive and their ranges are not well defined (open ended), so putting those into the hards of everyday users is kind of questionable.

Dito.

I think it is way "easier" for the user to has access to a control of angle steps instead of these insides of motor management. This would also be cool for e.g. robots with step motions of arms or sort of.

1 hour ago, Zerobricks said:

Your case is much more specific, with enough requests we might look into it too.

Still I hope somebody will join my request as it broadens the use :-)

[Toastie]

8 minutes ago, gyenesvi said:

steering power and steering speed that they can easily understand and tune

I don't get, how these two parameters could ever make a PID controlled loop working.

9 minutes ago, gyenesvi said:

The lego firmware only uses such parameters and they manage with it.

Really? It runs a PID loop by just supplying these two parameters? Then I believe it is not PID, but rather generic PI at most? Or just plain P? Which commands in the LWP protocol are you referring to?

Best,
Thorsten

[gyenesvi]

Just now, Toastie said:

I don't get, how these two parameters could ever make a PID controlled loop working.

I don't mean those parameters themselves, but the PID parameters could be derived from those by means of preset values and interpolation for example. Let's say you test a bunch of use cases from small models to large ones, and come up with PID parameters for typical cases, like those small/medium/large presets in the Buwizz app. Then you say large model corresponds to 100% speed/power, medium model to 70% speed/power and small model to 40% speed/power and you interpolate you internal parameters in between. For example when the user sets 80%, you interpolate between your medium and large values for each parameter. Let me know if it's clear what I try to mean.

Just now, Toastie said:

Really? It runs a PID loop by just supplying these two parameters? Then I believe it is not PID, but rather generic PI at most? Or just plain P? Which commands in the LWP protocol are you referring to?

Most LWP commands receive a speed/max power parameter.

[Toastie]

20 minutes ago, gyenesvi said:

Let me know if it's clear what I try to mean.

I believe so. However, if I am not misreading, the folks here want some fine-tuning on steering behavior rather than acceleration/deceleration of the vehicle (?) That means taking into account all the things @Zerobricks is listing above - and weight is only one parameter (weight affecting steering performance).

20 minutes ago, gyenesvi said:

Most LWP commands receive a speed/max power parameter

Yes they do. And they do result in "sort of appropriate" performance for moving a vehicle of "average LEGO PUp size". Nothing extreme allowed here (just apply a bit of "too much" resistance to a speed adjusted LEGO tacho motor operated from a PUp hub, and it totally freaks out). Which - as far as I am concerned - points me to: For speed control, TLG either applied generic average PID parameters in their firmware, or it is no PID they are doing, as said.

When it comes to fine-tuned controlled steering, though, I believe individually playing with the PID parameters is a must. Yes, generic parameters may be assumed as default, but then don't be frustrated, when they suck. Total weight may be one first approach - but I believe weight on the steering mechanism is more appropriate.

Best,
Thorsten

Edited April 8, 2023 by Toastie

[amorti]

55 minutes ago, Toastie said:

I don't get, how these two parameters could ever make a PID controlled loop working.

Really? It runs a PID loop by just supplying these two parameters? Then I believe it is not PID, but rather generic PI at most? Or just plain P? Which commands in the LWP protocol are you referring to?

Best,
Thorsten

PID, PI, P, LWP...

Good for you that you know what those mean, but I  shouldn't be forced into looking up these acronyms in order to play with a toy I bought.

I also shouldn't be forced to tick a box that says "I understand that these settings can damage the motor" just to make a servo do servo things.

And by the way, there's no model size or weight involved in my current issue. The buwizz cannot centre the medium angular motor even with nothing attached to it.

[gyenesvi]

55 minutes ago, Toastie said:

I believe so. However, if I am not misreading, the folks here want some fine-tuning on steering behavior rather than acceleration/deceleration of the vehicle (?) That means taking into account all the things @Zerobricks is listing above - and weight is only one parameter (weight affecting steering performance).

What I am saying is you don't explicitly need to take all those things into account. You only have to know that heavier models need more power for steering, and then you bump up the power percentage value. In general, if your steering is struggling for any reason, you bump up the power value. If it looks too strong and rips your build apart, you decrease the power value. Your steering is making too fast movements and overshoots and adjust itself too much? You decrease the speed value. Your steering is sluggish? You increase the speed value. You should not need to care what caused the wrong behavior, what you need to know is which parameter to adjust and in which direction and what's the order of magnitude you want to change (with the current parameters, we cannot even guess that intuitively). And certainly you don't need to know all the underlying mathematics of the PID controller. People who don't understand the math behind can only think in these intuitive parameters I believe.

[Toastie]

37 minutes ago, amorti said:

even with nothing attached to it.

Which may translate to a size/weight issue - as there is almost no inertia acting on the motor. Controlled loops need that input ("there is no additional inertia other than the motor gears") to function correctly.

Well, when wanting to have it all - superb controlled performance, fast feedback, remote control - on a LEGO model of unlimited parameter space (I guess we are not talking about a specific toy that you bought from TLG, you are maybe talking about a toy that you bought that was retrofitted with a 3rd party device, correct? Or even a toy that you designed from pieces that came from a toy) then yes, it may need a little tinkering. The alternative is going with what TLG has in stock. These devices don't really perform, as they are adjusted to simply provide average performance.

Best,
Thorsten

[2GodBDGlory]

2 hours ago, gyenesvi said:

You mean glue the motor plug into the Buwizz unit? That's like glueing your model together.. :) Not really a reusable solution..

No, that's not what I meant. My understanding was that the trans-clear plug part on the Buwizz popped out and was flopping around, and that it could be glued in place. However, your response makes me think that's probably not the issue, and that I should probably just be quiet given that I've never even seen a Buwizz! 

[Toastie]

20 minutes ago, gyenesvi said:

People who don't understand the math behind can only think in these intuitive parameters I believe.

Absolutely true!

But issuing speed and power to a PID algorithm, you submit two very different things: 1) a constant (speed = setpoint) and 2) a maximum value (power = a variable with a set maximum) = not a constant. The thing is, the PID algorithm calculates the power required to maintain speed. With the restriction of the max power allowed.    

In LWP, you submit the maximum power to be used for attaining speed, not just power - power is what the PID algorithm figures out within the constraint of max power. And with less favorable I/D settings, it will - or better - cannot perform well.

Best,
Thorsten

Edited April 8, 2023 by Toastie

[gyenesvi]

7 hours ago, Toastie said:

But issuing speed and power to a PID algorithm, you submit two very different things: 1) a constant (speed = setpoint) and 2) a maximum value (power = a variable with a set maximum) = not a constant. The thing is, the PID algorithm calculates the power required to maintain speed. With the restriction of the max power allowed.    

In LWP, you submit the maximum power to be used for attaining speed, not just power - power is what the PID algorithm figures out within the constraint of max power. And with less favorable I/D settings, it will - or better - cannot perform well.

Yes, I know this and I mean it like that in case of Buwizz as well, the power could mean max allowed power. I know my way of describing it was sloppy, but I only meant to illustrate with examples/ideas that the user could be setting some understandable high level parameters, from which the actual PID parameters could be derived by the FW.

7 hours ago, 2GodBDGlory said:

No, that's not what I meant. My understanding was that the trans-clear plug part on the Buwizz popped out and was flopping around, and that it could be glued in place. However, your response makes me think that's probably not the issue, and that I should probably just be quiet given that I've never even seen a Buwizz! 

No problem. So the issue is that the trans-clear plug has two small (miniature) clips inside it, into which the plug clicks when you insert it, and holds the plug inside. Those small clips broke off.

[Methes]

Different topic - how do you maintain your Buwizz motors?

So far I've used them only in outside vehicles so I make sure they're covered up to protect them from dust and road garbage, ideally putting them inside the vehicle and deliver power to wheels via drivetrain. That means using gears, joints and losing power on all of that. Direct drive would be best but also expose the motors more.

Also after a few hours of usage I see dried up something, probably motor oil, around the red axle holes I have to wipe off.

Do you dismantle the motors, clean them and oil them up? Or do you just not care and use direct drive right at the wheels and the ground?

[StudWorks]

47 minutes ago, Methes said:

Also after a few hours of usage I see dried up something, probably motor oil, around the red axle holes I have to wipe off.

When I bought my BuWizz motors they appeared to be lubricated (which I found cool), so I think it's just lubricant.

@Zerobricks When will the new update be available for iOS?

[Methes]

38 minutes ago, StudWorks said:

When I bought my BuWizz motors they appeared to be lubricated (which I found cool), so I think it's just lubricant.

Thanks, that's the word I was looking for.