[HELP] Generic Building Help Topic

[Aurorasaurus]

1 minute ago, m00se said:

I know you can use the BrickController2 App with a Playstation controller, but I'm really looking for a standalone solution. 

Have you heard of PyBricks? Racingbrick has some good videos on it, and theres a thread here and a website with what seems like plentiful documentation. It allows you to pair an xbox controller straight to the hubs, but the downside is you need to recode it for every new creation.

[2GodBDGlory]

3 hours ago, m00se said:

Not really a building question, but also not worth opening separate topic: Is there a (most likely not Lego) device capable of controlling two (or more) Control+ hubs? Something like a Playstation controller. I really hate having to use my phone to use the Control+ hubs for multiple reasons: building Lego is for me a way to NOT be on computer or phone for a few hours, I might need the phone to take pictures, I hate configuring these apps, but most of all: I want physical buttons to feel like I'm controlling my MOC. I know you can use the BrickController2 App with a Playstation controller, but I'm really looking for a standalone solution.

So something like this, but on steroids:

PyBricks is really the ultimate existing solution to this. It requires programming to set it up, but it allows for fully offline remote control with either PU train remotes or Xbox controllers directly connected to hubs. I'm also pretty sure they have support for multiple hubs (they were showing off a Liebherr crane fully controlled by an Xbox controller, for example l

[m00se]

Thanks guys, I'll get myself an Xbox controller

[mdemerchant]

On 10/31/2024 at 12:46 AM, dantheman12 said:

What are people's experiences with making responsive steering? Currently trying to find some solutions. I'm working on connecting the steering wheel to the front wheels of my 1:8 silvia, currently the axles follows like this: steering wheel > universal joint > worm gear driving a 16 tooth gear > 24:8 gear ratio > 2 more universal joints > 7L steering rack driven by a 12 tooth gear. I need to do some work strengthening the worm gear, but happy with the overall design, although it seems way too fancy. But the steering wheel can turn about 270 degrees when changing direction without moving anything. I know the u - joints have a bit of slack, so stacking them can cause this issue, but the way I've built the front end theres a bit of a lengthy path the steering drive has to take to get to the rack. Has to go about 6-7 studs to the left, and then a couple studs down. Has anyone dealt with this before? 

Thanks

Your question kind of got lost in the other discussions but here is my two cents.  The gearing is probably the major problem with responsiveness, not the U-joints.  Consider that 270 degree rotation of the worm gear will only turn the 16T gear 3/4 of a tooth.  This magnifies all the slack in the system and is going to make the steering super slow even with no slack at all.  You will be much better off to find a more direct routing of the steering and use closer to 1:1 gearing assuming this is a non-RC model.  If you really can't avoid sending the steering sideways it would be better to use a chain or even a bunch of 16T gears in a row rather than sticking in a worm gear to turn the transmission axis and U-joints to turn it back.  If you really, really have the turn the axis then use some bevel gears instead of the worm gear.

[Gray Gear]

4 hours ago, mdemerchant said:

Your question kind of got lost in the other discussions but here is my two cents.  The gearing is probably the major problem with responsiveness, not the U-joints.  Consider that 270 degree rotation of the worm gear will only turn the 16T gear 3/4 of a tooth.  This magnifies all the slack in the system and is going to make the steering super slow even with no slack at all.  You will be much better off to find a more direct routing of the steering and use closer to 1:1 gearing assuming this is a non-RC model.  If you really can't avoid sending the steering sideways it would be better to use a chain or even a bunch of 16T gears in a row rather than sticking in a worm gear to turn the transmission axis and U-joints to turn it back.  If you really, really have the turn the axis then use some bevel gears instead of the worm gear.

Overall good advice I think. I'd only like to add that using bigger gears helps to reduce play, so try to avoid using any 8t to 8t gear connections, or any 8t gears for that matter. Route the steering as easy as possible.

If you have space issues in the engine bay, you can drop the steering gear (12t) to the lowest brick layer, and put the steering rack above. This way you only lose 2 studs of height in the engine bay for the steering rack, but the gear will stick out a small bit under the car.

[dantheman12]

11 hours ago, mdemerchant said:

Your question kind of got lost in the other discussions but here is my two cents.  The gearing is probably the major problem with responsiveness, not the U-joints.  Consider that 270 degree rotation of the worm gear will only turn the 16T gear 3/4 of a tooth.  This magnifies all the slack in the system and is going to make the steering super slow even with no slack at all.  You will be much better off to find a more direct routing of the steering and use closer to 1:1 gearing assuming this is a non-RC model.  If you really can't avoid sending the steering sideways it would be better to use a chain or even a bunch of 16T gears in a row rather than sticking in a worm gear to turn the transmission axis and U-joints to turn it back.  If you really, really have the turn the axis then use some bevel gears instead of the worm gear.

Thanks for that, I put the worm gear in as I wanted the steering wheel to turn a realistic amount to each side when fully turning one way, but I underestimated how much the worm gear reduced the rotation. I'll have to experiement with a few other ratios - and will have to learn how to steering racks work in terms of rotation and teeth, never really thought about it before.

7 hours ago, Gray Gear said:

Overall good advice I think. I'd only like to add that using bigger gears helps to reduce play, so try to avoid using any 8t to 8t gear connections, or any 8t gears for that matter. Route the steering as easy as possible.

If you have space issues in the engine bay, you can drop the steering gear (12t) to the lowest brick layer, and put the steering rack above. This way you only lose 2 studs of height in the engine bay for the steering rack, but the gear will stick out a small bit under the car.

I've already got the gear on the lowest layer, but I'm going to try using some system bricks around the rack to tighten it a bit and see how that works as well.

But thanks again for the responses I appreciate it.

[Stereo]

10 hours ago, dantheman12 said:

Thanks for that, I put the worm gear in as I wanted the steering wheel to turn a realistic amount to each side when fully turning one way, but I underestimated how much the worm gear reduced the rotation. I'll have to experiement with a few other ratios - and will have to learn how to steering racks work in terms of rotation and teeth, never really thought about it before.

Usually they're quoted as a ratio of steering wheel rotation to tire rotation (roughly 10:1), so you can convert to that by figuring out the proportion of teeth on the steering rack to degrees at the tire.  Just as an example, if you have a 2 stud steering arm, which is pretty common, sin(1 degree)*2 studs = 0.035 studs, steering racks have 0.4 stud teeth, so if you had a 12 tooth gear on the rack, 1 tooth is 30 degrees and moves the tire 11.4 degrees (0.4/0.035), which is around 2.7:1 ratio already.  To go up to typical 10:1, 12:1 type thing you'll see in cars, you need another 4:1 gear reduction.

Edited November 3, 2024 by Stereo

[dantheman12]

18 hours ago, Stereo said:

Usually they're quoted as a ratio of steering wheel rotation to tire rotation (roughly 10:1), so you can convert to that by figuring out the proportion of teeth on the steering rack to degrees at the tire.  Just as an example, if you have a 2 stud steering arm, which is pretty common, sin(1 degree)*2 studs = 0.035 studs, steering racks have 0.4 stud teeth, so if you had a 12 tooth gear on the rack, 1 tooth is 30 degrees and moves the tire 11.4 degrees (0.4/0.035), which is around 2.7:1 ratio already.  To go up to typical 10:1, 12:1 type thing you'll see in cars, you need another 4:1 gear reduction.

when you mention steering arm, does that mean the steering 'hub', so then the distance from the point of rotation of the hub to the point where the tires rotate on the ground? and is the sin(1) is for something like the y component of the distance it steers for 1 degree? or am I thinking of something completely different? 

[Stereo]

5 hours ago, dantheman12 said:

when you mention steering arm, does that mean the steering 'hub', so then the distance from the point of rotation of the hub to the point where the tires rotate on the ground? and is the sin(1) is for something like the y component of the distance it steers for 1 degree? or am I thinking of something completely different? 

It's the hub, but the distance from the point it rotates (upper/lower balljoints or pins) to the point the steering connects to it.  The regular hubs usually use a balljoint in the pinhole and axle hole which are 2 studs apart.  Though of course you can build out other distances.  sin(1)*2 studs is the lateral distance that ball moves in 1 degree of steering, yes.

Edited November 4, 2024 by Stereo

[Aurorasaurus]

Nevermind, I solved my problem...

Edited November 8, 2024 by Aurorasaurus
Solved my problem

[Good old Lego builder]

Hi all, 

In have the Unimog 8110 for years on my shelve. Recently my kid noticed the pneumatic pump jammed. I have fixed that ( the pump had some dust issues) but I noticed now that when I put the batterybox on (in action) the crane-pneumatics works only one way (button to the right). When the switch on the batterybox is to the left (reverse so to speak) the pump works, but doesn’t seem to generate enough pressure, so the crane does not work then. 
Any clues at what is going on? This was never an issue.

[Zerobricks]

The pump probably needs to be opened up, cleaned and lubricated. 

[Good old Lego builder]

I have lubricated it. Can you explain why it works only one way around? I don’t see a difference in speed of the pump. (Hence why it has trouble lofting the boom)

[Zerobricks]

Could be uneven wear of the seal/sides.

[Good old Lego builder]

Ah! Ok, thanks!

[1gor]

Ladies and gentleman, did any of you tried to measure resistense in gears in following combinations (if someone did, which is the most efficient combination?):

- gear 24 to 24, then daytona differential -> 14 to 22 and hub reduction at the wheels

- gear 8 to 8 to 28 and then 12 to 28 tooth red differential with audi hubs

- gear 12 (spur) to 24, then 8 to 24 and then 20->28 (gray differential) with audi hubs

Thanks

I hope this is the right topic for that...

Edited December 7, 2024 by 1gor

[1gor]

I don't know if this is the right place, but you can make narrow axle using planetary hubs, new 7 x 7 suspension arm (at one side) with Daytona differential.

Link

(I have posted link because when I upload image, image is cut half from above...so to see it you jave to use magnifying glass...)

Edited December 15, 2024 by 1gor

[Jundis]

@1gor This is a great idea, will look into it for front axle of tractor!

[1gor]

Just now, Jundis said:

@1gor This is a great idea, will look into it for front axle of tractor!

Yes, I'm trying to make as narrow as possible axle with daytona differential and hub reduction...

[Lego Tom]

On 11/1/2024 at 9:36 AM, 2GodBDGlory said:

PyBricks is really the ultimate existing solution to this. It requires programming to set it up, but it allows for fully offline remote control with either PU train remotes or Xbox controllers directly connected to hubs. I'm also pretty sure they have support for multiple hubs (they were showing off a Liebherr crane fully controlled by an Xbox controller, for example l

I have tried and failed using an Xbox controller with the 42146 Crawler Crane. I was unable to get either one of my controllers to pair with the hubs. Someone recently posted a similar program for the crane using the LEGO 88010 controller, which I don't have but will soon be getting. The programs use the 1st up to connect and control the 2nd hub, so the controller is actually only working with the 1st hub. However, I understand NONE of the programming so please don't ask me any questions about how it's done.

[Aurorasaurus]

Hopefully this is the right topic for this:

What are the internal rules that you have for yourself when you're building technic creations? Or maybe, what is your design philosophy?

For me, the models I make are always play oriented, so being able to pick them up by the roof and shake them around and drop them without anything breaking is non negotiable.

[roeltheworld]

for me its that each model should include somekind of personal innovation somewhere.

[Milan]

47 minutes ago, Aurorasaurus said:

Hopefully this is the right topic for this:

Technic Pub is for...anything but Lego :)
I moved this here, but you can also open a new topic if you want.

[Carsten Svendsen]

3 hours ago, Aurorasaurus said:

Hopefully this is the right topic for this:

What are the internal rules that you have for yourself when you're building technic creations? Or maybe, what is your design philosophy?

For me, the models I make are always play oriented, so being able to pick them up by the roof and shake them around and drop them without anything breaking is non negotiable.

I should be able to drop it on the ground from standing height, and only have minimal cosmetic repairable damages.

[1gor]

To make realistic model as much as possible with minimal parts as possible no matter propulsion, functions,  looks or construction (I usually use as much frames as possible).