34 réponses à ce sujet

[Tolo]

Bonjour tout le monde

 

J'ai récemment fait une petite introduction à mon projet et ici je vais essayer de le détailler du mieux que je peux.

 

Le but est que ce robot accompagne les personnes en fauteuil roulant du quai d'origine au quai de destination (tout au long du trajet en train).

 

C'est un prototype, donc ses dimensions ne sont pas réelles (maximum un couple paumes) mais proportionnels et seront contrôlées par la carte ESP32.

 

Il se compose de plusieurs parties.

 

Le en charge du mouvement; la structure et les roues avec les moteurs respectifs, qui seront comme ceux des réservoirs (les appelez-vous des roues de chenille?) et quelques suiveurs de ligne pour à l'intérieur du train.

 

Celui en charge de la sécurité; où nous avons un capteur à ultrasons pour détecter les obstacles, des indicateurs LED, alarme avertisseurs sonore et un électro-aimant où la chaise sera fixe.

 

Celui en charge de l'accès à la plateforme robotique; une rampe escamotable, qui sera déplacée par un pignon-crémaillère puis basculée.

 

Celui en charge de l'accès au train; une plate-forme avec accéléromètre pour régler l'inclinaison afin que la chaise soit toujours à plat malgré l'inclinaison du robot lors de l'embarquement dans le train. Il intégrera également un capteur de force pour ajuster le contrôle.

 

La communication; de donner des petites instructions entre le robot et l'utilisateur (même si son fonctionnement est autonome) pour bluetooth.

 

J'ai la partie capteur sous contrôle, ce qui me fait grincer c'est la partie plus mécanique.

 

Enfin je partage que puisque l'opérateur ne me fournit pas les tailles des trains je prends un mètre ruban quand je monte dans le train et je fais du travail sur le terrain. 

[Oracid]

I suggest you communicate in English because, I am sorry, but your Google Trad is very confusing.

 

I think I understood, but I am not sure.

You want to make a robot tank which can ride on a train station platform and inside the train. Am I right ?

 

First of all, we have to know if the robot have to climb stairs. If yes, do the stairs are nosing stairs ?

[Tolo]

I'm sorry my french have confused you.

 

Anyway, you got it right.

 

Yes, it have to overcome stairs, exactly those of the train itself and they bother us because there are different train convoys (which have different stairs to get inside). For this reason I think to use a caterpilar/tank robot is a good idea.

[Oracid]

Yes, it is a good idea to make a tank for climbing stairs, but I have to know if the stairs have nose.

 

 

Here a few pictures to help talking.

 

 

 

[Tolo]

Some steps have noses and others don't, it depends on the convoy and not all the steps of the ladder are the same. 

 

Thanks for de pictures, the first time I don't had  understand (if stairs have nose or not).

 

Here som pictures about kind of trains that we have.

 

 

[Oracid]

I guess those trains are made by Alsthom or Bombardier. Please tell me. I used them in my all life when I was working.

 

With nose or without nose ! This is very important ! The problem is for the first step. Then every steps are alyke.

Without nose, the tank could be flat, which is easier. With nose, the tank must have an inclined front side, which is heavier, longer and more complex.

 

Please have a look at this video to understand what I mean.

 

 

[Tolo]

Yes, they are made by Alsthom, you have an eagle's eye!

 

I think the first step has no nose, but right now I’m not 100% sure. I had seen this video, but now I no longer remembered it's vital importance. Thanks for remember it. 

 

I try find it in the internet pictures whitout success. That’s why I’ll be doing fieldwork let’s see if I can finish confirming, why the approach really changes.

[Oracid]

Tell me one thing. You do not intend that the tank has to wear a person ?

 

You told me that you want to use an ESP32. May be you know the M5Stack which contains an ESP32.

The good thing is that with an M5Stack you can use a shield for big Lego servo. Those are clever servo, they can go to an angle of course, but they can too run to continuous rotation. You can too order it to do a number of turns. What else, it can be used as an angle sensor.

I have a few M5Stack, wich I never succes to connect, but I am a dummy . . .

Anyway, I think this could be a good way for your project.

 

Here, some pictures and links :

https://shop.m5stack.../products/basex

https://docs.m5stack.com/en/base/basex

https://www.hackster...-concept-8a1724

https://www.robot-ma.../13342-m5stack/

 

[Tolo]

In the prototype that I'm doing no, but in the work I am doing yes, where I will make a description of the features that the real model will have, which is intended to transport a person (with his chair).

 

The prototype is used to show the operating sequence. That's why I don't want it to be very big but proportional.

 

I have been looking at the M5Stack module and it is true that it is very well equipped to work with motors easily, anyway I think the control of the motors it allows is like the typical stepper motors.  But thanks for this discovery.

 

I had thought with the ESP32 for the number of I/O it has and because it is faster / more powerful than the typical Arduino because in the end the number of sensors and actuators is significant.

 

Here, the circuit that currently I have. Where you can see the stepper.

 

 

https://drive.google...iew?usp=sharing

 

Sorry for the link, I couldn't attach it.

[Oracid]

I had thought with the ESP32 for the number of I/O it has and because it is faster / more powerful than the typical Arduino because in the end the number of sensors and actuators is significant.

This up to you, but think you have to adapt your motor to Lego pieces. But with a 3D printer, all is possible.

 

Now that we have cleared the ground for a bit, can you estimate the size of the tank ?

Don't worry, it is just to make my mind and try to start the BOM.

[Tolo]

I have also seen that lego motors can be adapted to arduino connections, I will decide it later.

 

To maintain a certain proportionality, it would be about 31 x 16 cm. I know it’s long and narrow, but there are very narrow doors with big steps... but I understand it can be stable, right?

[Oracid]

 it would be about 31 x 16 cm. 

I am afraid it will be not long enough to climb stairs.

 

Please, look at the #10 video above, https://www.robot-ma...train/?p=114339 .

In the video, at 2'32", you can see that the tank must be hold up by at least 3 steps edges. If you have a staircase at home, measure the distance between 3 steps edges.

No problem for the width, it can be as narrow as you want. He will have a little difficulty turning on the spot, but in a train, you can't turn much.

 

This tank is 67cm X 42cm , 1,5kg. 

[Tolo]

I have calculated that the real model must be 5 times larger to be able to overcome the steps of the train, ie 80 x 155 cm.

 

I prefer make a prototype because de real mode slip through my fingers.

 

Precisely the videos you have made have helped me a lot in sizing the real model (still approximate) and see that with an angle of 30º it can access the train too.

[Oracid]

I have calculated that the real model must be 5 times larger to be able to overcome the steps of the train, ie 80 x 155 cm.

Well, this will be one the biggest robot tank !

 

Please, have a look at this : https://www.scewo.com/en/

 

 

[Tolo]

I had seen the second video, I didn’t know they had released a new model!

 

I have look it up and I saw that the maximum height is 20 cm. It’s really amazing that not even this monster could get on the train.

 

I go more in this way:

 

So this way people can keep the chair they currently have (and making the platform / robot 100% autonomous, it also allows its use in electric chairs) but for now the existing models I have found also have the limit of 20 cm.

 

Here, for when we work on the topic of loading, I found it awesome:

[Oracid]

This morning, I made this tank. It has 4 motors, but 2 are sufficient. The tracks are home made, Lego track and ruber sticked.

If you like it, I make the BOM.

 

Click me :

[Tolo]

It's so cool! Yes I like it, please make the BOM.

 

You use window D join as show in your videos, isn't it?

 

Thank you so much.

[Oracid]

You use window D join as show in your videos, isn't it?

Here the assembly is different. The secret is a special glue.

We will talk about this. 

Ok, I make the BOM.

[Oracid]

Well, here is the BOM !

 

I have widely evaluated the number of pieces. With Lego, it is interesting to have additional parts for possible modifications.

There are links to Chinese suppliers. The prices can be very interesting and I advise you to always compare. For motors, the difference is very important.

The CADA radio control, which is very reasonably priced, will allow you to evaluate a prototype that will work immediately before using an ESP32. The same goes for motors.

 

You must modify the suffix of the the file, from 'txt' to 'xlsx'. Hope this work.

 BOM-Tolo.txt   810,34 Ko   159 téléchargement(s)

[Tolo]

Thank you so much for the work and time.

 

I will compare the prices and once I have all the materials, I will keep you informed of each progress as well as any other doubts that may arise.

 

I will follow your advice and first try to make it work by radio control and then we will fight to make it work with Arduino.

 

So as say in catalan "poc a poc i bona lletra" that literally means "peu à peu et bonne lettre" but I think you say it like "qui trop se hâte, reste en chemin" or "qui veut voyager loin, ménage sa voiture"