Jeroen Ottens

You mean the kinked panels in the hydroplane (blue) and mineloader (yellow)?

Have you oriented the two universal couplings in an aligned way? You can orientate them in two ways, one straight and one where they are rotated 90 degrees with respect to each other. That is the wrong way, and will give you a non-uniform rotation output. I hope this is a clear enough explanation?

Hi, Thanks for the review and the photos Theo. I have updated the instructions (everyone that has bought the instructions already have received an email). I know you'll have to tear another supercar apart for this, but I do think it does look even better in red...

Nice shapes + a lot of functions for such a small package. I wouldn't load the container with heavy stuff though

Hmm, that's not easy, I can see why went with this solution... The only way I can think of is to remove the T-beam, place a 20T bevel gear instead and connect using another bevelgear (if a 36T fits that nicely centers it with the driveshaft I think). But you will have to take care with the bracing. (OTOH the torque needed to turn a fakeengine is very limited so you don't need a 9398 drivechain-like bracing)

Wow!!! That looks just amazing It get's better with every iteration. I love the colourscheme. Please keep the roof white (you mention it is temporary white), it shows the lines so much better than a black roof can. One tiny nitpicking detail: do you plan to substitute the row of 16T gears with something else (I just don't like this solution for translating a rotation input)? Other than that it is just great. How is the stiffness of the structure? Does it have longitudinal torsion stiffness?

I didn't know that about the extra pins giving so much reinforment, thanks for that. I really like the cleanliness of your design now (I hadn't thought of placing the 15L beams on the inside of the frames, but this makes for a very pleasing continuous edge). If you make the 15L beams grey as well it will look stunning I think.

Hi Owen, It is a fun optimization to do. Looks much better now. I like the solution to use the frames upwards oriented. But I think it can still be optimized a bit further: If you keep the structure as is you can use 3L pins to connect a frame to two 15L beams. Adding 3 pins to connect two beams does not add much in terms of stiffness (but doesn't hurt either). I remember seeing a post once about the effect of having longer overlaps between beams. The conclusion was that a minimum of one open stud between two pins was needed to get a good connection, but that making the overlap bigger didn't really add much more rigidity (law of diminishing returns). One thing to consider is to place the 15L beam that connects the two modules on the inside. It will make the distance between the module bigger (by 4 studs). You will still have a 5 stud overlap between the 15L beams which should give more than enough rigidity. Furthermore the beams don't stick out two studs which makes it better to withstand a vertical force on the edge of the beam (less moment). Finally the gap between two longitudal 15L beams is than 5 studs, so if needed you can add another 5x7 frame inbetween if needed. In official lego models you often see bracing that mechanically locks everything in place. I'm not sure it is needed on this structure, but you could make it with some perpendicular connectors on the outside of the longitudal beams and beams going over the top and bottom of the 4 5x7 frames block. If you use an axle to make the final connection you can make it such that the only way to bend the truss sideways is by breaking the parts. The way it is now the beams will slide of the pins. It will make the frame blocks bulkier though. So it has advantages and disadvantages, it will make the structure even stiffer, but if it goes wrong (the whole structure falls over) it may result in broken parts. Leg godt

While in real life triangles are indeed the way to for low weight, high rigidity structures, that doesn't automatically means that this holds true for Lego as well. The 5x7 frames are really good at providing a rigid mounting point in which moments can be absorbed, so they are not a bad choice as a basis for your structure. There is one disadvantage though, you are limited to the 5 stud height. Depending on the lengths you want to span (and the loads you want to bear) this might become a too restricting limit (adding multiple 5x7 frames above each other might be a solution, but you will have to be very careful in designing it such that the rigidity of the frames do not get lost in the flexibility of all the interconnections needed). For the horizontal part the largest stress will be in the top and bottom 'fibers' of your truss. For that reason it is of paramount importance that you have long, continuous beams at both top and bottom. Like you do on the vertical member (if you would put it on its side). For those beams it is also important that the holes are oriented sideways. Beams with holes pointing upwards will not provide a lot of loadbearing capacity (they rely on friction to be kept in place and the outer most fiber is basically a thin sheet with 90% holes. The fibers should be as far apart as possible (you could argue that you'd like the 5x7 frames in the seven stud high orientation because of that, but than mounting the 15L beam becomes a bit more difficult and ineffecient). For the vertical parts the loads are different: Some vertical load which can be easily absorbed by almost any Lego structure and only when thin enough buckling might become an issue. Torsion would not be my biggest worry, unless you foresee an application where a lot of torsion is introduced in the structure. So I think the vertical member is actually quite good to act as a horizontal member as well, but connect the 15L beams directly to the 5x7 frames. I would avoid any pins pointing vertically. I strongly discourage the use of the red elements (3L beam with 4 pins and 3 holes thingy). Since the pins are frictionless they have so much play in them that you basically loose all the rigidity of that wonderful 5x7 frame. Either use two 1 hole-2 pins-thingies, or just use normal friction pins. Final point of attention is the sideway loads. These high, thin and relatively light structures that you can build with this system are probably sensitive to people accidently brushing against it. Think of it as a structure made of straws connected only at the tips (with the straws mimicking your trusses). Unless you use triangles to connect those straws it is very difficult to get a rigid structure. But these are triangles of trusses, not so much triangles in the trusses. So after all these ASCII's I would summarize: The vertical part looks OK, but try to get rid of the red parts The horizontal part looks bad, better use the vertical part on it's side and redesign it such that no pins are vertical Think of a way to get triangles in the meta-structure (the diagonal part can be made with ropes if you make squares of trusses!)

In this topic you can find the solution I made to get a steering setup with both crabsteering and normal (Ackerman) steering on a multi-axle setup: http://www.eurobricks.com/forum/index.php?showtopic=89963 I still have to finish that boom...

The Magnus effect can be quite significant if you have a long enough path: So if you are living near a high structure there should be no reason why it can't be done with a contraption made of Lego

Well answered A lot of good progress. One remark though: adding LA's will not increase lifting power. It is still the same motor powering them, so unless you add more motors the lifting power is limited to the power of one L-motor. It is different for pneumatics. Adding more pneumatic cilinders in parallel will give more force (but you will need faster working compressors to keep filling that expanding volume). I do like the double LA setup with the sliding wormgear, but I guess it should be possible to reduce the width of that middle section by 4 studs by just meshing the opposite LA's with the same bevelgear (you have to rotate one LA 90 degrees or remove it's holder though)

This version had only the cyclic control. But the version below also has collective control:

Great model. I'd love to see some more photos.

That is an unusual car sir. But I love it Only the grille... The snake is a great touch, the tilting is good, but the shape is too square for my taste. Other than that it's a brilliant bold bolide

You can add the number of teeth of the two gears and divide the result by 16 and then you get the required distance in studs. So two 16 gears mesh at a distance of ( (16+16)/16 =) 2 studs (center-axle to center-axle), same for 24+8 and 12+20 gears. So gears that mesh directly with the new turntable are: 4 (gear doesn't exist) 20 (5 stud distance) 36 (6 stud distance) 52 (gear doesn't exist) Other gears might mesh, but then Pythagoras is needed to get a non-integer distance. The most heavily used example for that is the 20-16 mesh (ideal distance is 2.25 studs which is pretty close to sqrt(5), which can be made with a 1 stud offset in one direction and a 2 stud offset in the other).

Great video of some great models. You managed to get some serious steering angle on the last wheel, impressive. I suppose the steering angles do not scale down when the trailer is extended, or do they change proportionally with the length?

Hi, I would like to now your opinion on limitations in the rules. Each TC has had his own set of limitations (build something that transforms, your entry must have 4 motors controlled via IR, the model must fit in a box of X x Y x Z studs, etc.). If I speak for myself I enjoyed the competetion with the strictest set of limitations the most (in particular the MINI challenge with the 200 piece limit, the modelteam challenge with a limited size and the C-model competition). This may sound contra-intuitive, but I feel that the more 'open' competitions where everything is allowed, allow for so many possibilities that it somehow inhibits my creativity. I just don't know where to start. So what is your opinion on this? Do you prefer a challenge with some difficult requirements (like a low piece limit or a restricted part set). Or do you like challenges with the least number of boundaries and your preferred challenge is 'just build something beautiful'.

Yep, that works

Good progress! It is really nice to see the car evolving over the weeks One option to consider maybe: What if you put the 7x3 panel above the rearwheel facing backwards and upside down? That way the horizontal line below the windows stays intact. It does require the panel to be tilted as well to follow the curve of the 11x3 panels, I'm not sure if you have the space for that.

Sorry for not being more clear with my first comment. Kiwi Builder made it more clear I hope. If you take of the whole frontaxle, rotate it such that it faces backward (with the steering rack behind the frontwheels) and then put it back on it will work. Ole's picture shows an approximate Ackermann setup, in real life the setups typically have the linkage setup that you have, moving the steeringrack forward or backward (and adjusting the length of the links to keep the wheels straight) will also change the difference in steering angle between the two wheels. With some pretty fancy goniometrics you could calculate what the ideal ratios of the linkages should be, but as Nick Barrett already pointed out, in practice the engineers do not aim for the perfect Ackermann geometry, but optimize for other handling parameters (like the ability to corner fast).

Just reverse the setup... Imagine that the rear wheels are in front of the vehicle and the Ackermann is correct.

Congratulations to the winners

What kind of light did you use? It could be that your lightsource is missing the red tones? Ever since the bulbs have been banned most LED/energy saving lamps are quite monochromatic and blueish, I suppose (but maybe some physicist can confirm) that that will make red more dull.

Absolutely insanely impressive.