Didumos69

Thanks, but I think there will be more competition over the next two weeks. I managed to make a setup with 3 hands. I think this means the fictitious LEGO time system I had in mind will have 4 hours in a day (2 in a clock cycle) and 5 minutes in an hour . All hands perfectly aline every 2 hours and every single hour the minute hand aligns with the second hand. Btw, I also managed to extend the autonomy to 16 minutes by gearing down from 20:1 to 18:1, but this will all change when I install the hands.

Thanks! I like watching it too. The sound is addicting. Aha, that makes sense. At least I don't need to worry there is something weird with my setup. To get rid of the non-LEGO weight I will eventually make this a standing clock. I'm thinking of four large inclined pillars with the pendulum in the center. Thanks. I decided to not synchronize this clock with real time, even though two clicks almost correspond to a second. I like challenges like the escapement, the wind-up mechanism, the optimal gear ratio and multiple concentric hands and I don't like being tied to specific RPM ratios for the hands.

I finally had some time to work on the wind-up part. It took some trial and error to get the gear ratios and the length / weight of the pendulum right. With my first attempt I needed a very long pendulum with a lot of weight. At that point the autonomy was about 3 minutes. After some more gearing up (currently the pullback motor is geared up with a 20:1 ratio) and improved bracing (I once more experienced how important this is to make gears run smoothly (rattle happily)), the autonomy now is 12 minutes, but that really seems to be the max. When I add the hands of the clock, I might have to reduce the gear ratio, which will also reduce the autonomy. I hope I can keep it around 10 minutes. The wind-up mechanism relies on a differential: the rear output is blocked when the clock runs normally, when you wind-up the clock, the rear output slips. It appears that when the pullback motor is wound-up completely, it starts off with a lot of power for a relatively short interval. Then it has a very long interval with relatively constant power and finally it ends with a short interval of little power. Another thing I noticed, is that when I wind-up the clock a little - not fully - while the clock runs, the clock accelerates shortly and quickly enters it's steady state again. I can't really explain why. The whole setup currently works equally well with a short / heavy pendulum and with a long / light pendulum. For now I opted for the short pendulum, because eventually I prefer having a standing clock. Here's a video of the current state. It's quite a long video, but I wanted to give an impression of how constant the speed is. The next step will be to add hands. I decided to allow my self to come up with a fictitious LEGO time system (e.g. a LEGO day might have 3 6 LEGO hours and a LEGO hour might have 9 minutes), as the main challenge for me is to have a model that shows how a clock works rather than having a clock that tells the exact time. I'm aiming for 3 hands, each with a different speed.

Congratulations to you and your wife! I suppose she's the one that provided proof for the incircle formula within minutes. I wish you a happy marriage. And merry Christmas to everyone!

That's a very amazing piece of work! I'm indeed looking for my own solutions, but I sure can use some inspiration, so I watched your topic anyway. Thanks!

You are right. It was a leftover of the original setup. Good to read your confirmation on the mass assumption . Btw I think my escapement's swing angle is quite low.

I noticed that too. I used it in a pendulum setup and it works realy nice, but it's still sensitive to a varying driving force. I know that the frequency of a pendulum does not rely on the mass of the pendulum, bu I think adding mass will make it less sensitive to a varying driving force. So what I'm thinking of is to turn the mechanism around and integrate the pullback motor in the pendulum. That would also add some weight. This is what the escapement currently looks like. And this is how it behaves with pendulum:

That is pretty ingenious! Especially the use of the diff. And you're right I'm looking for a studless solution. I made a little progress. Instead of the single pin solution in my previous post, I used 2 bevel gears with 3 pins with tow ball. At least I have something oscillating.

I'm glad you've been able to take out all issues ! Congrats on a very nice and accessible 4x4 buggy! I hope many will enjoy building it.

You will have to figure out what to use it for, for yourself of course, but I wouldn't mind you making a clock too. We have to see whether I will make it to the finish line and it would be a pitty if you would regret not making a clock afterwards. Good luck with this and I will sure be following your next steps.

Thanks for the support guys! This is quite outside my comfort zone, because the essential mechanisms can not be invented in LDD. That's a nice solution! I like the simplicity and compactness of it. That's what I'm looking for too. Al though I will probably not be using studded parts.

First attempt to make an escapement failed. The stepper is not capable of keeping the whole thing in motion. Next attempt will be something like this. The frame is part of the pendulum.

Pentagon Clock This is a wind-up pendulum clock powered by two pullback motors. This clock is not true to real time but rather focuses on features such as a wind-up mechanism, pin wheel escapement and three concentric hands. It has been built completely in-system and can be reproduced without any fine-tuning, except for making all gears run smoothly of course (LXF-file here). The clock has a very consistent autonomy of 18 minutes. It features: A wind-up mechanism - A differential is used to prevent the hands from running counterclockwise when winding-up the clock. One of it's outputs is locked by default and slips during wind-up. Pin wheel escapement - Instead of using teeth, the escape wheel has three round pins that are stopped and released by a scissors-like anchor, which has been integrated in the pendulum. Three concentric hands - Planetary gears and a differential house make for a fictitious LEGO time system with 2 hours in a clock revolution, 5 minutes in an hour and 30 seconds in a minute. The pentagon-shaped clock face refers to the 5 minute hour. All features have been originally developed for this contest.

Now that we are quoting models, Charbel's Volcano RS has just the right abstraction level, balance and consistence imo. The panels catch the essence of the car without covering everything.

Yes. I also replaced the 6L axle with a 4L axle. This is the primitive I used to repeat: That makes sense. I didn't know about frieze groups. Interesting .

The most simple Wallpaper p6 I can come up with:

+1. I wouild love to see something free-style from your hands !

You might want take a look at the 3D counter part of this thread and a thread about platonic bodies.

I get the patterns online, mainly from https://en.wikipedia.org/wiki/Pentagonal_tiling and https://en.wikipedia.org/wiki/Wallpaper_group, but translating them to LEGO is my part. I did come up with this pattern myself though (it's a p6m wallpaper): I've always been intrigued by tiling planes and spheres, so I know quite a few techniques. I ever contributed to the art of cartography with a self-derived tiling-based equal-area map projection.

Another Wallpaper group p4g (4*2) (below you see the primitive that I used to repeat):

I can resonate with practically all of the things said here. A very accessible book comes to mind, which has been a valuable guideline throughout my career sofar: 'Machine Beauty: Elegance And The Heart Of Technology' by David Gelernter: "When something works well, you can feel it; there is a sense of rightness to it. We call that rightness beauty, and it ought to be the single most important component of design. This recognition is at the heart of David Gelernter's witty argued essay, Machine Beauty, which defines beauty as an inspired mating of simplicity and power." It addresses the fact that Technology is more - if not only - successful when it goes hand in hand with elegance. He speaks of rightness when there is good balance between function and design. I think the things mentioned here, like the peek a boo approach, the coherence, a good balance between looks and technical functions, etc, all attribute to that rightness.

+2

@DrJB, you started the same discussion before. My point of view has not changed: Lego is all about making 'models'. And to me (sorry, I have an engineering background) 'model' means: Simplification of a system (or thing) that brings about one or more aspects of that system's (or thing's) nature. Models allow us to zoom in on certain aspects while leaving other aspects out. So it's all about what exactly do you want to tell with your model. Take a look at Nico71's Mechanical Calculator. It's an amazing machine and we probably all regard it as something beautiful. Not because of it's looks, but because of what it can do, and that it can be done with Lego bricks. So in this case Nico71 zoomed in on the 'how it works'-aspect rather than the aesthetic aspect. Now when it comes to cars, there is something delicate going on: There are typically two prevailing - yet quite opposed - aspects that make a car appealing: 1) the looks and 2) what's inside. On the one hand a car should look smooth as if it was cut from a single piece of stone and shaped by the wind. On the other hand it should cover up as many nifty features and powerfull functions as possible. So when it comes to supercars, it doesn't amaze me that using panels has gained popularity over the years. They make it possible to address both aspects. Personally, being an old-school Lego fan, I like it the most when a Lego model captures the essence of a car - be it a real car or an imaginary car - with a minimal set of lines. Just like a portrait painting, it doesn't need to be as realistic as a photo, as long as it captures the essence. Source: http://www.scottdesi...-im-working-on/ EDIT: I would like to add one more thing: When I started regaining interest in Lego Technic, all Lego supercars I found on the internet appeared to me as insects - also the more recent ones. I had to get used to them first before I started to actually perceive them as great designs. Just to illustrate that it's all a matter of perception.

Yet another one: Wallpaper group p4 (442). This one is based on Pythagorean tiling. It uses only 3 different parts .

Something based on different shapes: Another Wallpaper group pgg (22x)