[MOC] [WIP] The Command of the AT-AT

[Tracytron]

18 hours ago, Smitty500 said:

Chihuahua. Cha-wa-wa. A small dog?  You know,"Yo Quiero TacoBell?" google it.

oh i didnt know it was spelt like that lol

also to anyone that thought i thought it would actually take a good chunk of the wait off of it i didnt i just thought it might help like by like 1% or perhaps even lower actually PROBABLY even lower lol

[Tommy Styrvoky]

Motorizing this model is probably not possible, you would have to start from scratch, as the legs require routing of parallel linkages, and some method of providing power to rotate the arc on top of the feet, to keep them parallel to the ground. the upper hip joints would cause a lot of issues with being too bulky to route power/be rigid enough. The biggest issue would going to be providing sufficient power to the model, you would probably need at least 2 Xl motors to power it, maybe 4? so 1-2 8878 batteries. Another issue would be synchronization, if the legs got out of sync, the model would topple over, so a mechanical mechanism could be used to automate the walking motion. It would also be a potential option to add a steering mechanism, if you are to shift the hip joints side to side.

yes it's possible to do, but this scale may be too large, and with the current design, it would require an entirely new design, and would compromise the details for functionality. 

My guess is the only major limiting factor to the fact that any torque bearing axle on this model will be twisted and broken, so every joint would need a turntable to support the weight. 

Wheeled vehicles are easy enough, as the multiple suspension components bears the weight, though with this model 2 legs have to be strong enough to bear the whole weigh. Maybe someday I could get to building a 1/2-3/4 scale of this that's motorized, though the main issue is the high center of gravity. I will start with an AT-TE first.  

So from a practicality standpoint, I think just continue trying to make this model the most detailed AT-AT, motorizing this is a whole new set of major engineering headaches. 

Edited November 3, 2016 by Tommy Styrvoky

[dmaclego]

Really good points, Tommy, but I can't say I agree 100% :) .

Having my own AT-AT sleeping peacefully in a trunk, I keep wondering, from time to time, if making such a huge beast mobile is possible at all. Initially I thought: no, absolutely not. Of course, LiLmeFromDaFuture  , just like any of us, would have to start his project all over (parallel linkages are just one of many reasons). But let me go quickly through your other suggestions.

- About arcs on top of the feet - in my opinion, you don't need to provide power there. They could just hang there - on an axle, for instance - and be "self-levelling".  It is a four legged machine so it cannot topple forward or backwards if all other joints are rigid (controlled mechanically). If you look closely at AT-AT stride, you'll find that at least three feet ALWAYS stay on the ground. And a big LEGO AT-AT actually may stand on three legs, as it was proven by my model, when I (acccidentaly, of course) missed the axle hole as I was attaching one of the legs ;) .

- About upper hip joints - you are right, they would require tremendous power if they were to swing powered through an axle or turntable. But please note that most of the large AT-AT designs (not mine, however) utilize vertical beams that connect outer ends of hips with vehicle's main body. Now, imagine an actuator  instead of those beams. That could work :) .

- About synchronization - very true. An adder mechanism would be necessary to sum up power of several XL motors and only then, from a single shaft, you could distribute power to four legs, carefully setting gears or levers. Complicated, I admit, but this method solves the problem of (lack of) synchronization.

- About steering - even more true :) . I virtually can't see how this could be done. Not with a model that weighs 6 or 7 kilograms.

- Generally: builder of such a beast would have to forget about providing power to upper hips, lower hips and knees any other way than simple mechanical levers. No gears. No pneumatics. Nothing fancy. Currently, I'm trying to construct a skeleton of such a leg where I could only move the upper hip joint, and power of that movement would be transfered (in the same time) to lower hip joint an knee joint. The good news is that amplitude of movement does not have to be large - several degrees, maybe ten. But everything else is bad news :) . For instance, two liftarm beams connected together take up two studs of space, which is the entire thickness of the leg - it's not possible to hide them. Not to mention the fact that even pins with friction are terribly loose when long beams and serious forces are involved.... So, theoretically, anything is possible but today I'd only say: maybe, maybe. Time will tell.

But maybe the host of this topic is a better engineer :) . I hope so!

 

Edited November 3, 2016 by dmaclego

[Tommy Styrvoky]

4 hours ago, dmaclego said:

Really good points, Tommy, but I can't say I agree 100% :) .

- About arcs on top of the feet - in my opinion, you don't need to provide power there. They could just hang there - on an axle, for instance - and be "self-levelling".  It is a four legged machine so it cannot topple forward or backwards if all other joints are rigid (controlled mechanically). If you look closely at AT-AT stride, you'll find that at least three feet ALWAYS stay on the ground. And a big LEGO AT-AT actually may stand on three legs, as it was proven by my model, when I (acccidentaly, of course) missed the axle hole as I was attaching one of the legs ;) .

- About upper hip joints - you are right, they would require tremendous power if they were to swing powered through an axle or turntable. But please note that most of the large AT-AT designs (not mine, however) utilize vertical beams that connect outer ends of hips with vehicle's main body. Now, imagine an actuator  instead of those beams. That could work :) .

- About steering - even more true :) . I virtually can't see how this could be done. Not with a model that weighs 6 or 7 kilograms.

The main reason for the leveling the feet, is because they could get caught on things, using gravity would work, but It wouldn't be too difficult to have a linkage that keeps it parallel to the knee joint.( potentially less issues leading the the whole model falling over.)

For moving the hips, a cam mechanism would work, I was thinking it would drive a linkage at the end where the leg attaches to the hip.Though it would have to be rather robust, maybe a worm gear driving a small turntable, as any worm gear driven axle would be twisted beyond recognition without proper reinforcement. This would be a necessity, as it allows a small displacement of the leg vertically, so it can travel forwards without scraping on the ground. These parts would lift all of the weight of the model.

For steering, the easiest solution would be a mechanism that would change the stride length on one side to be shorter, while maintaining the cadence and synchronization of the legs. Maybe shifting the point of the driving linkages to the legs would work.( it would function like a differential in a car, one path is shorter than the other, thus slowly steering the model..)

I think it would be simpler to just use the hips to support the model, and lift it, and the leg motion linkages could just be routed in the center of the legs, though It could be possible to fit it within a 2 stud wide space, but it would probably have to be wider to be structurally solid. Maybe it would be easier to use a NXT or EV3 to control it, as the hips would have to be individually controlled, if it's on 3 legs at a time. so 8 motors would be needed, or some sort of transmission to route power to a hip and a leg (3 motors). Though it would have to be rather durable design, or just use worm gears to power the leg motion and hip motion.

Edited November 4, 2016 by Tommy Styrvoky

[LiLmeFromDaFuture]

On November 3, 2016 at 1:14 PM, Tommy Styrvoky said:

…and some method of providing power to rotate the arc on top of the feet, to keep them parallel to the ground.

Lego recently came out with a new gear element in the Bucket Excavator set: 

I thought that could work, because of its similarities to the actual arc on the AT-AT, but with the gear teeth on the inside it cannot connect to the gear linkage throughout the legs.  Equally worth to mention of why this element would seem impractical to use, that two of these place together to form a half circle will dramatically upsize the scale, and the limits of the Lego's biggest motor could not possibly support the immense weight of the walker at the current scale.

[Tracytron]

Another solution could be to operate each leg (including hip) separately. And also I never meant to sound like I was actually asking you to do such btw. I was just suggesting random ideas. I'm ambitious I guess idk. But really I never meant to put pressure on you to actually make it motorised I was just proposing ideas, though I disagree that even two EV3 motors could do such lol, in my opinion you'd have to buy some small but powerful motors instead and actually tinker with the electronics to link it up to a EV3 computer or any other system of circuitry plus modify the motor to be compatible with Lego axles in the first place. Apart from that I completely agree with Tommy on his solution for the problem though.

Edited May 31, 2017 by Tracytron

[LiLmeFromDaFuture]

11 hours ago, Tracytron said:

Another solution could be to operate each leg (including hip) separately. And also I never meant to sound like I was actually asking you to do such btw. I was just suggesting random ideas. I'm ambitious I guess idk. But really I never meant to put pressure on you to actually make it motorised I was just proposing ideas, though I disagree that even two EV3 motors could do such lol, in my opinion you'd have to buy some small but powerful motors instead and actually tinker with the electronics to link it up to a EV3 computer or any other system of circuitry plus modify the motor to be compatible with Lego axles in the first place. Apart from that I completely agree with Tommy on his solution for the problem though.

No pressure at all.  Though, I did need to convey as clearly that I could not possibly proceed with the novel idea, considering how I designed the legs; the articulation has to continue down through the legs and to the knees—again not possible with the progress I have shown so far…

Nevertheless, still making progress, and looking into a motorized AT-AT.

Edited May 31, 2017 by LiLmeFromDaFuture

[joebiwankenobi]

Just checking in and hope all is well! I'm currently working on recreating your excellently designed snow speeder. I've got a stud.io file complete just need to order parts. Have you worked on your AT AT in the last year? No doubt you had more important things to do. It's hard to make time for Lego anymore. 

[LiLmeFromDaFuture]

2 hours ago, joebiwankenobi said:

Just checking in and hope all is well! I'm currently working on recreating your excellently designed snow speeder. I've got a stud.io file complete just need to order parts. Have you worked on your AT AT in the last year? No doubt you had more important things to do. It's hard to make time for Lego anymore. 

It is seriously in deep, real deep develop; like a complete structure overhaul with yet again the feet and legs.  These two members are such a critical part of the AT-AT to stand soundly, so its structural integrity demands the utmost dedication to support the walker with ease.  Rest assured, the details will remain the same for the most part, and even improved with the new elements introduced constantly, but the internal redesign will considerably refine the whole design process in a straightforward direction within these parameters or requirements to render a solid build… aaa

On another thought, I am also making considerable updates to the snowspeeder (redesigned fuselage, cockpit, and a new play feature); I look forward to sharing that soon!

 

Lastly, thank you for holding an interest in this project, I really appreciate it!

[Kristof]

Many people hold interest, make no mistake about that haha :D Feed us some pics as soon as you can, ok?!

[LiLmeFromDaFuture]

On 2/15/2018 at 2:18 AM, krisandkris12 said:

Many people hold interest, make no mistake about that haha :D Feed us some pics as soon as you can, ok?!

 Sure thing! 

[Evolved Turtle]

To quote Orson Krennic, "Oh, it's beautiful." Fantastic moc so far! Can't wait for the final product.

[LiLmeFromDaFuture]

@Evolved Turtle  Many thanks!  The rate of progress on the walker has tremendously increased to my amazement (building itself to an extent); I believe it will see its completion before the coming summer, then will come its grand reveal!

[Warmerhouse]

I just read your post from beginning to end today. Imho the AT-AT Walker is the Holy Grail of MOCs. To make it motorized with scaled detail would put me in total meltdown of the mind. I'm just content with your MOC scaled. Thanks to Lego for allowing us to build whatever our imagination and parts availability limits. It has kept my interest well into my adulthood, and deserves an applause. 

Props to lego for giving us the building blocks, kudos the the community for taking them to a whole other level.

[LiLmeFromDaFuture]

On 3/27/2018 at 7:51 PM, Warmerhouse said:

I just read your post from beginning to end today. Imho the AT-AT Walker is the Holy Grail of MOCs. To make it motorized with scaled detail would put me in total meltdown of the mind. I'm just content with your MOC scaled. Thanks to Lego for allowing us to build whatever our imagination and parts availability limits. It has kept my interest well into my adulthood, and deserves an applause. 

Props to lego for giving us the building blocks, kudos the the community for taking them to a whole other level.

Many thanks!  Without fail, the possibilities of Lego impresses me beyond amazement; it is such a wonderful medium to express imagination! 

Mechanizing a Lego AT-AT does sound like a dream come true, though, more than likely, not feasible with the design of details, but certainly a perfect goal for an even larger AT-AT.

Regardless, I believe this AT-AT, that nears completion and to see its reveal soon, will indeed emerge a true gem, because it has felt so to me; reminiscing back in 2012, when I started with the idea of making a genuine minifig-scale AT-AT walker, and to see now how far it has gone—truly amazes me!

[Kristof]

To my knowledge, there has been only several (single digits) of walking AT-AT models made to date, and I am talkinng any kind of model, not just lego. Most 'motorized' AT-ATs work on similar principle as the past lego set, being able to poorly drag the feet and wobble forward and backward. The only model that actually performs well that I found is this one

VIDEO

It seems a lot is involved, maybe including active stabilization, or at least the mechanics of the motion has to be tweaked tremendously so it stays upright. That being said, I think that with current (and perhaps ultimate) limitations of Lego, properly walking motorized AT-AT is a dream.

That, however, doesn't take away not even a slightest bit from my anticipation of this model! Summer is coming :D

[anothergol]

LiLmeFromDaFuture, the new 2x2 triangle tiles are buyable everywhere now, they're a game changer for me, surely you will have a use for them. On the head, for ex.

 

[LiLmeFromDaFuture]

@krisandkris12

I have seen that video too and many times over!  It mesmerizes me geekfully like the stop motion in ESB; its locomotion progresses smoothly, yet gives way to cumbersome feeling!  

A motorize AT-AT already presents its challenges, and it multiplies readily with a larger scale to accommodate all those monotonous, gape-inducing, details we pleasure, along with the mechanizing.  Considering this all has drawn me to a possible application of the walker mechanized in a fashion similar to what this build has done for his AT-ST: 

AT-ST w.i.p by Carl Greatrix, on Flickr

 

 

@anothergol The 1/4 octagonal ones, or something else I am missing? 

 

 

[anothergol]

1 hour ago, LiLmeFromDaFuture said:

 

@anothergol The 1/4 octagonal ones, or something else I am missing?

These

I'd have paid gold for just a few when they were anounced, now Bricklink is filled with them & they're cheap.

[LiLmeFromDaFuture]

I am surprised how I seem to miss this despite the many times I have checked that category to ensure the parts used are in production and relatively easy to get, but yes, these will be especially perfect for the head!

[HERMANtheSMASHER]

I don't mean to revive an old thread, but i'm new around here and just ran into this build thread. I read the entire thing in a sitting and got to the end and was wondering if you ever released this version you were working on? I saw you made a different version that was a bit smaller, but this model was looking so amazing in the details. The head you developed still looks like one of the best i have seen thus far. I'm just getting into this world of lego's and built many Official Lego Star Wars sets and was looking for a new good challenge and I LOVE the AT AT and AT ST. I was wondering if there is any chance that you would ever consider releasing this? I looked at Cave God's and Jhaelego's with the full interior and raskolnikov's looks to be in similar scale to the second one you developed and there all amazing models. I was possibly leaning towards building jhaelego's AT AT or contacting him to see about building his AT M6, but that is a huge model and massive undertaking. Then I came across yours today and read the whole thread and said damm this is the one I need to build, details are amazing, legs look very sturdy, a small possibility to pose it somewhat vs some others. 

Please let me know if there is any chance of building this. Thanks! Amazing job!!

[LiLmeFromDaFuture]

@HERMANtheSMASHER

No problem here!

 

Yeah, I somewhat abandoned this project to solve its issues I had, with a more manageable scaled down version.

Despite how extravagant the head looks, my biggest issue with this project falls here.  IT IS ABSURDLY FRAGILE.  The visor itself is a deal for trouble!  Each of the triangular pieces connects ever so delicately to whatever shoddy way possible.  It all holds very loosely to the model, so any painstaking attempt to align them perfectly could unintentionally crumble it.  

So much of troubles with fragility with this project as a whole frustrated me so much to Kragle it and seal up the mouths of every little part that defied my quest for ULTRA DETAIL

Then I figured (with the much-needed help of criticism for using glue ) what difference exists between my ambition and simply putting together a model kit if it both takes glue to complete it?  Well, finding various elements to replicate certain detail has its fun, but it's no saving grace for the cheapskate use of glue.

I very much look forward to resuming progress on a larger scale AT-AT!  The smaller one is amazing in its own right, but as you mentioned, does not carry the extra detail like this one.  Though I do not know what will return from this project, or what new will developed since the growth I made with building LEGO, but time will tell!