[EV3] Mindsensors Multiplexer

[oracid]

24 minutes ago, Hanso said:

 it could be handled as one large brick with 16 motors.

Do you know this, http://www.mindsensors.com/ev3-and-nxt/21-multiplexer-for-nxtev3-motors 

You may have 12 Lego servos with only one EV3.

[Jim]

2 hours ago, Hanso said:

This robot was controlled by 4 EV3 bricks in daisy chain modus, so there was no special inter-brick communication. It was programmed with the standard EV3 programming environment, and because of the daisy chain modus, it could be handled as one large brick with 16 motors.

That is exactly what I have done with my robot. I do have a problem with the slave motor blocks which keep running. I was about to create a topic for it. Basically what happens is that the slave blocks don't end when they are supposed to end. So after running a motor for 2 seconds, the blocks keep running. Have you encountered that problem?
(I can post the link to am article online by someone who had the exact same problem, but I need to look it up)

1 hour ago, oracid said:

Do you know this, http://www.mindsensors.com/ev3-and-nxt/21-multiplexer-for-nxtev3-motors 

You may have 12 Lego servos with only one EV3.

I have been thinking about this multiplexer. I will add one to my next order at mindsensors. I need to get an IRLink and some cables, so I will order it soon. Is there a limit to the number of motors running simultaneously? I reckon running 16 motors on the same brick can result in some issues? Batteries will probably drain pretty quickly.

[Jim]

It does require an external battery btw. I prefer a solution with EV3 bricks, but I might give it a go.

[oracid]

Yes, with the multiplexer, you need a battery. But you can use a Lego Lipo and connect it with a cable than you have cut in one side.

I am not sure, but I believe the output to servo from EV3 are 5V. But I think this servo can stand 12V. I think the Lego Lipo is 7.4V.

I have already use a 9V battery and all was OK.

Edited October 26, 2018 by oracid

[Jim]

I do need an external battery for my ledstrip too, so maybe I can get a bigger battery to power the multiplexer(s) and ledstrid. Can I still read/measure the motor rotations with the multiplexers?

• Supports speed control, timed rotations, encoder based rotations, etc.

it seems you can.

[oracid]

Yes, here I show some picture with parameters, but you can download all documentation in this page http://www.mindsensors.com/ev3-and-nxt/21-multiplexer-for-nxtev3-motors

Only one picture is allowed. sorry.

 

[oracid]

Yes, it will be good idea to start a new topic.

Anyway, my last picture.

https://www.flickr.com/photos/146789920@N05/shares/03d99Q

[Jim]

I have created a new topic for the Multiplexer.

[oracid]

Thank you @Jim

In this topic, https://www.eurobricks.com/forum/index.php?/forums/topic/156061-variable-geometry-tank-climber/ you can see one of my tank which use the NXTMMX multiplexer (previous version) because I needed 6 servos, as you can see.

4 servos for the tracks and 2 servos for the actuators.

 

[Jim]

Sweet! I will take a close look tomorrow