Mbot1 Self-balancing


#1

Hello everyone,
I’m sorry, I’m not english fluent, but I will try to aks my questions on these community.
So I’m a teacher and I begin to use Mbot V1 on classroom.

i would like to do a self balancing Mbot like this :

Fond on this webpage : https://medium.com/xodlang/xod-and-pid-powered-self-balancing-mbot-6c420600271e

But I don’t understand everything on this site.

Is there any docupent to do this project ?

Thank you


#2

Hello there! May I ask what problem specifically you are having? I can’t really figure out the site either.


#3

Sorry @Casnytcha - As a first impression, I do not believe that this (as shown in your image) is at all possible !

This model needs, at the very least, a Me 3-Axis Accelerometer & Gyro Sensor module (as shown below) connected to the mBot to enable it to react to changes in attitude; and your picture does not show one of these. Without this module, it would be impossible to programme the mBot to balance.
image
However, having read through the webpage you found, it does show this module (but only in the very last video) - beware, this sort of programming is VERY complex.


#4

Yes, I have understand that we need these Gyro Sensor (you can see it on the top, the black square)

and use a PID to control the self-balancing (like used for house heat control).

But, I think they use a specifical software ?


#5

Hi @Casnytcha

You should use the Forum’s search bar and enter ‘self balancing’ . You will find quit a lot of information here and I’ve responded to related posts several times - here are a couple of links that you may find of some value:


#6

I wasn’t sure it works like this on mbot1 becose on this topic it was for ultimate bot.


#7

The principles of balancing are the same for whichever bot. However, your original image (where it was impossible to see a Gyro module) shows it using mBot’s own motors which are simple DC motors. I’m fairly sure that PID control is only possible when using Encoder motors.


#8

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Inside the red circle you have the gyro module


Here the link with a video (movie) .

So it is perhaps possible only with mbot2 :frowning:

No, I just look on the net to see différences with mbot2. they have encoder motors, but they are on blue color. The one of the mbot1 are yellow like on the movie.


#9

I know now that the black square is the gyro module - BUT its just a black square!


#10

I don’t realy understand your answer…a joke ?


#11

so suspicious…


#12

No, not a joke. The black square was clearly the side of an RJ25 socket - but no hint of what module might have been there.


#13

I’m surprised it works, the board is on backwards.


#14

Dc motors are also placed differently.


#15

The positioning of the motors and the board mounted inside the mBot chassis both make sense (to get the best possible weight distribution over the wheels).


#16

@CommandeR Maybe that’s why, but I do not see how it could distribute weight because the board is on one side.


#17

No - I agree @Rosco but that seems to be the best possible positioning for such a device - see my notes at:


#18

I think it will be better to place the mother board outside the frame, but with little spacers, and the battery inside (like the picture).


#19

I think so, too. Do you have all the components necessary to complete this project?


#20

No, I’m waiting to determinate all accessories I need for the 7 mbots we have in school (differents projects).
Because I would’nt have to order many times for little things.

But, the real question is how to program these one. I try to understand what they use on the example, but I don’t know how to do.