LEGO Mindstorms and Robotics General Discussion

[Danil]

On 12/18/2021 at 9:18 PM, Zerobricks said:

Might be a bump, but got myself a 51515, because I wanted to learn to do some robotics along with the general building. So far it's been very fun and can't wait to progress enough to build and program my own creations.

Zerobrix!  Congratulations on your purchase!  This is a very nice set!  Perhaps he will help you to perfect your creations and touch on the polishing of bouwizz a little!  I am sincerely glad for you!

[Flaming Bricks]

Question, what is the difference between Lego Mindstorms and Lego Boost? I believe that both require coding and robotics and that both are used at some schools 

[dr_spock]

Boost is geared towards younger children and Mindstorms towards older ones. 

[Flaming Bricks]

Makes sense, my siblings have used Boost, but Mindstorms also looks fun too

[glowytheglowbug]

just curious whats the usual website to go to for lego technic+mindstorms creations as i want to make a lego mindstorms arm with a shooter on top of a tank and after using the LEGO design for the arm it was way too wobbly and wiggled everywhere also, im using 3 ev3 bricks (you can see my robot base there in the bottom picture) also, would mechanum or omni wheels help with turning as currently when turning with too much load it can barely turn.

also im curious on getting spike prime or essential is there a clear difference in the items? because they seem very similar

[Mr Jos]

8 hours ago, glowytheglowbug said:

I want to make a lego mindstorms arm with a shooter on top of a tank and after using the LEGO design for the arm it was way too wobbly and wiggled everywhere also

Could you upload some photos to a site like Flickr and then post them here, so we can see what you're building and how to give advice? If you mean a turntable that you want to make stable, I have a pretty good one build in my 6DoF robot, I use it in my sorter with swinging arm aswell.

[Jim]

8 hours ago, glowytheglowbug said:

just curious whats the usual website to go to for lego technic+mindstorms creations

Eurobricks 

(there are Facebooks groups, but they don't offer elaborate help when it comes to the build itself)

Why don't you create a separate topic and explain your problemin more detail. Maybe we can help.

[glowytheglowbug]

4 hours ago, Mr Jos said:

Could you upload some photos to a site like Flickr and then post them here, so we can see what you're building and how to give advice? If you mean a turntable that you want to make stable, I have a pretty good one build in my 6DoF robot, I use it in my sorter with swinging arm aswell.

basically i want a really stable arm design as currently im using the one lego has on its website and when my robot accelerates and stops it swings around, also the motor gets backdriven easily (im planning on mounting my full auto gun design on it)https://www.flickr.com/photos/195407294@N08/shares/4cn4e1 (thats the base) and the video is the gun mechanism im going to use.

 (

[Mr Jos]

16 minutes ago, glowytheglowbug said:

basically i want a really stable arm design, when my robot accelerates and stops it swings around, also the motor gets backdriven easily (im planning on mounting my full auto gun design on it)https://www.flickr.com/photos/195407294@N08/shares/4cn4e1 (thats the base) and the video is the gun mechanism im going to use.

I think you should be able to use a 60Tooth turntable to put the gun mechanism on. Then you will need to put 4times a 12T gear around it to turn it around, and remove backlash. 

In this video (I tried to start the video where you can see 4x 12T gears around the 60T) you can see that it can move without backlash, even with a huge weight on it.

If you need a bigger turntable, the one underneath with banana gears (yellow and black) might be an option. It rotates freely but does not break, even when a big load is on 1 side or even outside of the gear.

Edited April 4, 2022 by Mr Jos

[Jim]

12 minutes ago, Mr Jos said:

If you need a bigger turntable, the one underneath with banana gears (yellow and black) might be an option. It rotates freely but does not break, even when a big load is on 1 side or even outside of the gear.

Is there an image where I can see the innards of the bigger turntable? I am still planning on making a big robot (yes, I do, really) and I have been looking into big turntable designs.

[Mr Jos]

3 hours ago, Jim said:

Is there an image where I can see the innards of the bigger turntable? I am still planning on making a big robot (yes, I do, really) and I have been looking into big turntable designs.

Yep, I just made 2 screenshots from my 6DoF PDF instruction;

Here it's on a high baseframe as I wanted my robot to stand higher, but it's possible to make it really low profile. I do that in my pin sorter.

 

Hoping to see from both of you some content soon, as it's pretty dead here in the Mindstorms forum (I actually sometimes think to just post my builds in Technic subforum to get more views/reactions).

@Jim If you want more info for the turntable I can send you the PDF from the sorter or 6DoF, anything to get someone back in robot building :D

[Jim]

2 minutes ago, Mr Jos said:

If you want more info for the turntable I can send you the PDF from the sorter or 6DoF, anything to get someone back in robot building :D

Sounds like a deal 

You can read more about my LEGO future in this topic, but I am definitely planning on building more Mindstorms. I have been in contact with Laurens a lot lately and I have been testing Pybricks as well. The possibilities are endless and I don't see any limitations anymore.

This is exactly the solution I have been looking for. I was looking for a big turntable without losing the possibility for exact rotation measurement. This seems to fit the bill.

[glowytheglowbug]

7 hours ago, Mr Jos said:

Yep, I just made 2 screenshots from my 6DoF PDF instruction;

Here it's on a high baseframe as I wanted my robot to stand higher, but it's possible to make it really low profile. I do that in my pin sorter.

 

Hoping to see from both of you some content soon, as it's pretty dead here in the Mindstorms forum (I actually sometimes think to just post my builds in Technic subforum to get more views/reactions).

@Jim If you want more info for the turntable I can send you the PDF from the sorter or 6DoF, anything to get someone back in robot building :D

if you could can you send me the turntable instructions? (also i dont have those huge gears so whats the part number?) if possible i dont need one too accurate or heavy as its going to be mounted on my tank but i do want one that is sturdy and dosent just break itself when it falls over.

14 hours ago, Jim said:

Eurobricks 

(there are Facebooks groups, but they don't offer elaborate help when it comes to the build itself)

Why don't you create a separate topic and explain your problemin more detail. Maybe we can help.

basically i just want to know some websites to talk to lego technic experts whenever i want to find some creative inspiration (with credits of course) or when i need a little help (also i have no idea how to make a topic im rlly new to eurobricks

Edited April 5, 2022 by glowytheglowbug

[Jim]

6 hours ago, glowytheglowbug said:

if you could can you send me the turntable instructions? (also i dont have those huge gears so whats the part number?) if possible i dont need one too accurate or heavy as its going to be mounted on my tank but i do want one that is sturdy and dosent just break itself when it falls over.

Hi. Please be careful with quoting an entire post with images. That is frowned upon. Please remove the images or quote a single image if you are highlighting something. Thanks

[glowytheglowbug]

1 hour ago, Jim said:

Hi. Please be careful with quoting an entire post with images. That is frowned upon. Please remove the images or quote a single image if you are highlighting something. Thanks

oh sorry i just re read the rules sometimes when reading things i just space out i apologise 🙇

[Jim]

39 minutes ago, glowytheglowbug said:

oh sorry i just re read the rules sometimes when reading things i just space out i apologise 🙇

No worries mate. 

[Mr Jos]

9 hours ago, glowytheglowbug said:

Basically i just want to know some websites to talk to lego technic experts whenever I want to find some creative inspiration (with credits of course) or when I need a little help (also I have no idea how to make a topic im rlly new to eurobricks)

***I added this***

- The new topic can be made by pressing the red button "Start new topic" (if you go outside this topic, in the mindstorms subforum you will see it). You will be asked to give it a name (choose something usefull about your subject/question). And then put your text.

- When quoting you can go inside the quote and remove/add parts like I did with your quote, as Jim said best to remove photos if they are within the last 20 posts, people will be able to see them there if needed, and not make scrolling/data use to big. You can also change your previous posts by clicking the blue "Edit" button at the right bottom corner of your posts, and then remove/add something if you did forget it.

- I and many others here on Eurobricks will help you if you ask good questions, with that I mean, show what you already have, tell what you want to do/make. I myselve like to make complex machinery, and some of them I offer instructions for on Rebrickable (for small fees), as they are complex machines with programs that take many hours to make/test.

https://rebrickable.com/users/Mr_Jos/mocs/ Here you can see all MOC's (My Own Creations) I have instructions available for. Many other people make these PDF or photo instructions and post them on this site aswell. Some are free, some ask money. You can look around on that site and search for things you might want to get inspiration from, there are near 100'000 instructions already.

- The turntable is in 2 of the MOC's in the link I posted above, but if you need a really sturdy one you might want to add a 60T turntable extra inside the big yellow gears and connect them on both sides. That will make a very strong turntable that is also stable and allows smooth rotation. The yellow gears alone already hold firm with my design and roll smooth as it uses a kind of bearing (can be seen in step 7 in the photo above).

- The gear parts are 8x these you will need, along with the other parts inside offcourse (they are available in yellow or black only);

https://www.bricklink.com/v2/catalog/catalogitem.page?P=24121#T=S&C=3&O={"color":3,"iconly":0}

Edited April 5, 2022 by Mr Jos

[ninoguba]

On 4/4/2022 at 7:58 AM, Jim said:

I am still planning on making a big robot (yes, I do, really) and I have been looking into big turntable designs.

Curious what big robot you have in mind that will need big turntables. Looking forward to see and read about it here. 👌

On 4/4/2022 at 11:22 AM, Mr Jos said:

Hoping to see from both of you some content soon, as it's pretty dead here in the Mindstorms forum (I actually sometimes think to just post my builds in Technic subforum to get more views/reactions).

I agree ☝️ Wish the Mindstorms forum is as active as the Technic forum. Not much feedback happening on the topics here.

Edited April 18, 2022 by ninoguba
Ok fixed the quote.

[Jim]

16 hours ago, ninoguba said:

Curious what big robot you have in mind that will need big turntables. Looking forward to see and read about it here. 👌

 

I am thinking about the 11x11 curved gear racks per wheel unit. I will start a concept topic soon-ish.

@Mr Jos We might consider moving Mindstorms back to Technic. I was planning on posting my robot topic in Technic because I will be needing some Technic building suggestions. It's great to have a dedicated Mindstorms topic, but if it isn't active (enough) there's nothing preventing us from calling this venture a failure and move things back to Technic, like we did with Scale Modelling.

[Jim]

Technic is okay with it.

 

[ninoguba]

10 hours ago, Jim said:

Technic is okay with it.

Woohoo!

[Aris]

Hello!

I want to run a code with 4 Control+ L motors using Robot Inventor hub at 100% speed (with RI app), but the hub flashes with "red light" and suddenly stops, which means that has an overload.

I used the test program of the hub, to run 4 motors at 100% speed and worked fine without overload indication.

I tried to code 3 Control+ L motors at 100% speed and worked fine.

I wonder if running 4 L motors has to do with the code (I tried 60, 70, 80, 90 and 100% speed but still same result).

Any ideas?

Edited October 12, 2023 by Aris

[dustblue]

does anyone know why the angular motor exists at all? I mean what is angular motor can do but PU L motor can not? I saw lego specifications and the torque is not much bigger for angular motors, but the mechanical power is definately less than PU L motors. So other than the shape(4 more pin holes other than axle hole), what's the angular motor's advantage against regular motors?

I also tested a robot hub in 51515 could handl PU L and control+ hub could handle angular motors. So no compatable issue either, than why...

[Zerobricks]

57 minutes ago, dustblue said:

does anyone know why the angular motor exists at all? I mean what is angular motor can do but PU L motor can not? I saw lego specifications and the torque is not much bigger for angular motors, but the mechanical power is definately less than PU L motors. So other than the shape(4 more pin holes other than axle hole), what's the angular motor's advantage against regular motors?

I also tested a robot hub in 51515 could handl PU L and control+ hub could handle angular motors. So no compatable issue either, than why...

You can mount a wheel directly on them for simpler, more accurate and more robust attachment/bearing.

[dustblue]

2 minutes ago, Zerobricks said:

You can mount a wheel directly on them for simpler, more accurate and more robust attachment/bearing.

Indeed! Using two of the pin holes. Thanks! Didn't thought about that. So it's all about the shapes not the functions I guess..