Some dumb PU questions

[High_Admiral]

56 minutes ago, zephyr1934 said:

The lack of any official documentation is stunning given the amount of functionality Lego is building in to the PU app and the price they are charging for the hubs.

I quite agree, it seems like a very half-baked system instead of just updating the PF system with this functionality.

[Phil B]

7 minutes ago, High_Admiral said:

I quite agree, it seems like a very half-baked system instead of just updating the PF system with this functionality.

Wait until they stop updating the PU app in a few years ... which will happen inevitably (anyone try to download the Nexo Knights app recently?). Let’s just hope the homebrew apps continue to be available, otherwise all this expensive PU stuff will be useless (sort of).

[Toastie]

30 minutes ago, Phil B said:

Wait until they stop updating the PU app in a few years

Oh yes. As with all software based platforms. In the beginning, the possibilities seem to be unlimited - but eventually the hardware trails further and further behind ... software/firmware all evolves further and further - and then: Pull the plug, say "sorry to have to inform you" or something in that direction, make something new.

I really also agree with the total failure of keeping the LWP3.0 protocol documentation where it was, when the faulty initial version was published.

But then: They need to sell new stuff. Time doesn't wait for them, it keeps on rolling ... lets find out the hard way, what the lifetime of LPW3.0 and PUp hardware will be.

Best
Thorsten 

[Tcm0]

I'm pretty sure that the PUP hardware itself will be usable for a long time. There is enough documentation (official and inofficial) for community support and there are enough BLE capable devices that will always work with the PUP hardware (look at all the Raspberry Pis with BLE). The main question is how this support will look like then.

[Pendra37]

I know it is not Lego but you can always move to stuff like the ESP8266 to control electronics remotely, cheaply and easily. The base unit is like 3 USD, and is the size of an AA battery. You need another an AA sized LiFe battery to power for a good while. Add some wiring to the actual motor and you are good to go. The base unit has only 4 I/O channels with PWM which is enough or front, back and speed controls. Lights and sounds, not so much but oh well. Some time ago I made a simple system where I controlled my H0 train with my mobile phone or PC using that thing. 

Edited February 25, 2021 by Pendra37

[Toastie]

37 minutes ago, Pendra37 said:

ESP8266 to control electronics remotely, cheaply and easily.

Oh for sure! My Crocodile is commanded around by an ESP32 clone 

That was not exactly the point: Just imagine you want to build something and motorize it. And besides building skills you have acquired serious knowledge in many other areas but C++ programming, BLE hardware and so on. In other words: You need to use what TLG offers ... 

Best
Thorsten

 

[LegoDW]

So I have been having some success with the app.  Got a train to come out of a siding, run around the layout a few times and put itself back into the siding...repeat.  Also got two trains to index themselves at my station, that is change tracks (passing siding at station).  Required one going backward thru a switch but works good.  Added way to many steps to maximize the trains swapping movements.  

If I was a kid, I never would have figured out the Power up app programming.  Agree, for the price TLG charges for stuff one would think they could afford to properly support this product.  They give you a sizeable book to build a pirate ship, but to program a train you are on your own....

 

Anyone find aftermarket PU plugs?  As TLG does not provide extension cables need to make your own.

[dr_spock]

PV Productions sells Powered UP extension cables for 24.95 euros each. 

The PU connectors are not too hard to draw up in CAD and then 3D print them yourself.

[Bartosz]

11 hours ago, Pendra37 said:

I know it is not Lego but you can always move to stuff like the ESP8266 to control electronics remotely, cheaply and easily. The base unit is like 3 USD, and is the size of an AA battery. You need another an AA sized LiFe battery to power for a good while. Add some wiring to the actual motor and you are good to go. The base unit has only 4 I/O channels with PWM which is enough or front, back and speed controls. Lights and sounds, not so much but oh well. Some time ago I made a simple system where I controlled my H0 train with my mobile phone or PC using that thing. 

Just one cell? My understanding is that it'd give you the 3.2V to fullfil the chip needs (3.3V), but what about the PWM channels? How do they handle motor current draw(not too mention voltage is low), is the chip you're mentioning particularly tailored for motors?

[Tcm0]

3 hours ago, LegoDW said:

Anyone find aftermarket PU plugs?  As TLG does not provide extension cables need to make your own.

There are currently PUP extension wires available at aliexpress: https://de.aliexpress.com/item/32871195908.html

[Pendra37]

2 hours ago, Bartosz said:

Just one cell? My understanding is that it'd give you the 3.2V to fullfil the chip needs (3.3V), but what about the PWM channels? How do they handle motor current draw(not too mention voltage is low), is the chip you're mentioning particularly tailored for motors?

I use AA sized LiFe batteries. Those output 3.2-3.3V and not prone to swelling or blowing up. The driving power is not going directly through the ESP, it is switching a L9110D H-bridge. With that FET in the middle, the power for the ESP and the power for the motor can come from different sources. It can control the usual DC motors just fine with the usual issues. Such as on low frequency/speed, the motor has an audible whine. I added a calibration before the game session. It goes from 0-100%, 100%-0, 0-+100% and 100% to 0. Note down at what level the train starts to move, what level the train stops and at what level it starts to whine. With that, the start happens on the set start level and then decreases the frequency to just over the whine level. If you change the speed so the train would enter the whine region, the train immediately stops.  

[Bartosz]

5 minutes ago, Pendra37 said:

With that FET in the middle, the power for the ESP and the power for the motor can come from different sources.

How do you power the H-bridge ?

 

Good stuff about the calibration, gotta hate the whining :)

[Pendra37]

27 minutes ago, Bartosz said:

How do you power the H-bridge ?

Wherever it is convenient. From the same battery parallel, from another battery or from the analog powered rails. 

[Bartosz]

38 minutes ago, Pendra37 said:

from the analog powered rails. 

How do you pick up power from rails?

[Toastie]

6 minutes ago, Bartosz said:

How do you pick up power from rails?

I believe @Pendra37 meant the DC input line to the board? 

Best
Thorsten

[Pendra37]

1 hour ago, Bartosz said:

How do you pick up power from rails?

That was not strictly for Lego. I used it for a H0 train, there, the DC power is pumped to the rails. I also did it for Brio toy trains, hence my need for AA battery size. I built the controller to fit into the one AA battery slot and the AA sized 3.2V LiFe (14500) battery into the other slot.
Actually, now that I think of this. if you have the 9V battery box that uses AA batteries, you can apply this to Lego without problem. Get 4x AA sized 14500 LiPo batteries and set it up in a 2S2P layout. That will give a nice constant 7.2-8V and 2000+ mAh capacity. 1 AA sized 14500 LiFe hooked up to power the ESP and 1 ESP + H-Bridge. If you hook up the H-Bridge output to the battery box's output you actually have a WiFi controlled 8V power source with PWM. Front, back, speed control. 
   

Edited February 26, 2021 by Pendra37

[Bartosz]

Thanks, lots of useful tips!

[UltraViolet]

  If I were to consider buying a PU hub just so I have at least one in my collection, and taking into consideration that software and firmware capabilities are still evolving, which one hub right now offers the widest app and accessory compatibility?  Do any of you have a particular personal preference for one over another based on any other attributes, such as physical size, power source/battery type options, or port count?

  Then there is the consideration of third-party options - The freshly released BuWizz 3.0 Pro is looking mighty-attractive right about now.

[Tcm0]

Powered Up Hub, Boost Move Hub and Control+ Technic Hub are pretty much on pair in regards of compatibility. The move hub has problems with technic motors, the technic hub doesn't support a direct connection to the remote.
The move hub has 2 integrated motors, 2 pup plugs and a gyro sensor. It's relatively large. The normal hub only has 2 ports. The technic hub has 4 plugs and an integrated gyro sensor, so it's the most flexible one but it's not exactly small.

The move hub has a bit less processing power than the other hubs which might become a problem if you want to run programs independently on the hub (currently only possible with pybricks).

[dr_spock]

5 hours ago, UltraViolet said:

  If I were to consider buying a PU hub just so I have at least one in my collection, and taking into consideration that software and firmware capabilities are still evolving, which one hub right now offers the widest app and accessory compatibility?  Do any of you have a particular personal preference for one over another based on any other attributes, such as physical size, power source/battery type options, or port count?

  Then there is the consideration of third-party options - The freshly released BuWizz 3.0 Pro is looking mighty-attractive right about now.

It depends on what you plan to do with them. 

For me, I prefer the 2 port train hub since my main use for them is running trains at our club's train show events. I use rechargeable NiMH batteries. They last an hour or two depending on the size and weight of the train. It is not hard to swap in a set of recharged batteries and recharge the depleted ones if you designed your MOCs for easy battery box access.  Also the PU remote works with it so I don't have to use the Powered UP app on my tablet.

 

 

[UltraViolet]

I see everyone is getting 'on board' with the PU to PF mods! 

  I tend to build smaller creations, so the 2-port hub would be a benefit there.  But on the other hand, I greatly appreciate that I was able to install the official SPIKE app natively on Windows 10 and have immediate access to block-based coding and USB or bluetooth connection options to a SPIKE Hub.  (The same applies to the combination of Mindstorms Robot Inventor software and hub.)  This would make acclimatizing to the PU universe of hardware and programming a lot easier, certainly when just roughing out builds on the workbench.  I would hope that the block coding scheme used in the SPIKE and Mindstorms Robot Inventor apps is common to that in the Powered Up mobile app.

  One other thing - is there any major downside to the SPIKE hub not supporting Bluetooth Low Energy?  Is this the same for the other 6-port hub?

[Tcm0]

8 hours ago, UltraViolet said:

I tend to build smaller creations, so the 2-port hub would be a benefit there.  But on the other hand, I greatly appreciate that I was able to install the official SPIKE app natively on Windows 10 and have immediate access to block-based coding and USB or bluetooth connection options to a SPIKE Hub.  (The same applies to the combination of Mindstorms Robot Inventor software and hub.)  This would make acclimatizing to the PU universe of hardware and programming a lot easier, certainly when just roughing out builds on the workbench.  I would hope that the block coding scheme used in the SPIKE and Mindstorms Robot Inventor apps is common to that in the Powered Up mobile app.

  One other thing - is there any major downside to the SPIKE hub not supporting Bluetooth Low Energy?  Is this the same for the other 6-port hub?

Actually the spike hub supports bluetooth low energy. It's just not really supported at the moment, but it can serve as a "base unit" for the other powered up hubs. There is a python library to control the hub directly with the powered up remote: https://github.com/Vinz1911/PrimePoweredUP

The scratch-based SPIKE environment is not really similar to the powered up app. You can download it and take a look if you want to see the differences. There is an official scratch extension for powered up I think but I'm not sure how good it works and how good it works especially for your purposes.