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The motorbike contest is over so I managed to make some new progress (the biggest succes is the belt from rubber parts now runs smoothly enough not as in previous versions):

IMG_20210218_094752

 

IMG_20210218_094807

 

I also started to mount pneumatic hosing....I'm not 100% satisfied with that but it's OK now.

IMG_20210218_094733

And a photo from the underneath:

IMG_20210218_094719

Thank you for visiting!

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Hi everyone.

It has been a while since the last update of this project has been posted and some things have changed.

I decided to not to build the Panther 2 (I'm sorry) but the larger one, the Tiger 6s, which in conclusion means adding an extra axle and reworking some parts of the machine.

n8x_1307.jpg

Current features:

Drive by 3 C+ XL motors (1 per axle)

Front wheels steering by 1 Spike Prime medium angular motor

Articulated steering uses the C+ L motor

Each of rear axles steered by C+ large angular motor (no.15), 2nd axle connected to the "pedestrian safety mechanism" (I don't know how to say it better)

Pendular rear axles 

"Harvesting" motor already placed, but connected only to the front belt (between front wheels)

Some moving details in the interior

In total, there are 8 motors now (next 5 or 6 are about to come ;-) and 3 hubs (2 C+ smart hubs and one train hub, one C+ hub will be added)

Some photos (sorry for quality):

IMG_20210909_115631

 

IMG_20210909_115617

 

IMG_20210909_115607

 

IMG_20210909_115554

 

IMG_20210909_115207

Here's how the medium angular motor's mounted.

IMG_20210909_115003

 

IMG_20210909_115035

The train hub is hidden, but the box is still bigger than the original one.

IMG_20210909_114834

And finally, the biggest problem faced so far - the Powered up app (which isn't even supported on my phone now).

The problem is that when the machine is in the "all wheel steering mode", both rear axles turn in different angles (as well as in every vehicle with more than 1 steered axles),

but when the vehicle is in the "crab mode" the rear axles turn same.

Bacause I'm not very good at programming, the best solution that came to my mind was to limit the speed of one motor when "all wheel steering" is engaged.

The downside of this solution is that you have to return the wheels to the middle before changing a steering mode *huh*

Could someone with more knowledge about the Powered up app help?

Screenshot_2021-09-09-11-59-33-879_com.lego.common.poweredup

Thank you all for visiting & comments are welcome.

Edited by MP LEGO Technic creations

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Nice update. Glad to see the new progress :thumbup:
Love all the brick built sections, given the size, it is possible to put a nice amount of details and realistic proportions. Will follow this.

Please reduce your image size (max is 1024).

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Wow, a very interesting and beautiful project. The combination of articulated steering and classic steering looks cool. The number of features planned is impressive. I wish you a successful completion of the mock and will follow the progress with interest.

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Off topic but gotta love how non-military equipment company has models called Panther and Tiger :pir-laugh:

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A really beautiful model and also a really beatiful Lego model implementation.

I´ll follow your evolution, I really like it.

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3 hours ago, MP LEGO Technic creations said:

The downside of this solution is that you have to return the wheels to the middle before changing a steering mode 

What happens when you switch the mode without returning to the center?

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@MP LEGO Technic creations, as a programmer (I definitely love separating my work and hobbies) I personally would try to make these steering modes mechanically:

  1. "Crab mode" = all rear axles + front section are turned at the fixed angle.
  2. "Small steering" = only rearmost (a little) and foremost axles are rotated.
  3. "Full steering" = all rear axles + front section + front axle are turned at different angles.

So, I would make two steering systems:

  1. Line #1: Front section + middle axle + A-input of "steering subtractor" at the rear axle.
    Using only this line you will have a "crab mode" steering.
  2. Line #2: Front axle + B-input of "steering subtractor" at the rear axle.
    Adding some rotation to this line together with line #1 you will additionally turn the front axle and turn more the rear axle, so it will have a bigger angle rather the middle one.

* The "steering subtractor" here could be made as a differential with two inputs (steering lines) and one output.

Added: I realize that it is an incredibly difficult scheme and I have never seen something similar in any of the existing MOCs but it looks very technic-ish variant ever :blush:

Edited by Void_S

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I like it! I think this is the first model I've seen to use quite so many hubs! Fortunately you seem to have space for them all...

Powered Up isn't supported on my phone anymore either.

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Here is my approach:

800x400.png

The motor connected to B changed it's position when i switched the value for a. I'm wondering why you aren't using the steering blocks for... well... steering :-)

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@Andman I have just tried yout solution and here's my experience with it.

I looked to your photo and carefully recreated the same program in my app, but even there's no mistake, it can't work as described.

After some tries I realized that evyrything works well, except "the steering blocks" (that's why I don't use them at all).

Then I switched the "steering blocks" to the speed control ones and everything is OK, now it can control the speed of both motors (and it works same as my own idea, but seems to be easier).

In conclusion, I really don't know what's wrong with the "steering blocks", they ignore slides and joysticks, as well as the stop button. The motors just rotate and can't be stopped ;-)

Anyway, thanks to your suggestion, which at least simplifies my own one. :wink:

Edited by MP LEGO Technic creations

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Did you connect the steering motors to the steering shaft/rack? The motor wants to find its endpoints, so it needs to calibrate. It first spins to one side, and if it finds it’s endpoint, it spins to the other side. If it doesn’t find one, it just keeps spinning. I had the same problem with the PU motor spinning when I first build something with it. It’s a shame TLG didn’t offer more documentation on how to use the PU motors and app, but that’s another discussion.

Btw, I really like agriculture machines (either real or in Lego version), and I love this one. Great eye for detail, and also many working functions.

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@Rebel_Lego Oh, you're right.

Even though, there's a problem. The rear axles use worm-gear-operated gear racks, which is, at the end, quite a big reduction (to handle the model's weight) and calibration process still thinks, that it isn't at the end yet, which almost caused planetary gear reduction damage (tries to stop it manually ended up with some minor injuries ;-).

I'm definitely impatient enough to calibrate (four different motors) even when switching from "programming mode" to the "controlling mode".

Articulated steering uses 2 small LA, which also don't affect the calibration process at all.

However, nice to know, how the steering blocks actually work :laugh_hard:

 

Edited by MP LEGO Technic creations

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1 hour ago, MP LEGO Technic creations said:

I looked to your photo and carefully recreated the same program in my app, but even there's no mistake, it can't work as described.

After some tries I realized that evyrything works well, except "the steering blocks" (that's why I don't use them at all).

Hm, are the motors for the steering supposed to act like servo motors (automatic return to center) or like in the 42070? While there are some bugs in the Powered UP app, i never had any issues with the steering block.

Could you explain how you steering system works?

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6 minutes ago, MP LEGO Technic creations said:

@Andman This problem was already solved (I tried loose motors, not connected to anything), but now there's an issue with calibration, because of some gear reductions (please see my previous post).

Sorry, didn't see the mentioned post. did nor reload the page :blush:

But now it makes sense. You aren't using a return to center steering. That makes several things more complicated. I would strongly recommend to use some kind of clutch to prevent damage, if you would like to keep you current steering mechanism. But if possible, change it to return to center steering (motor as a servo). That way you can easily switch between steering modes.

BTW, really great project. Looking forward to see more progress!

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