2GodBDGlory

This model is the start of a potential series of drivetrain models. The idea for this came from the original Koenigsegg Jesko's unique transmission design. Between the transmission and several other notable features, I had considered building a full 1:8 scale Jesko model, but I'm still hesitant to spend much time on bodywork that could be spent building interesting mechanical features. Eventually, the idea struck to build a sort of display model showcasing the drivetrain of this car, but without the encumbrances of bodywork. In the end, the model is essentially the drivetrain and rear axle of the car, on top of a paneled base, with a pair of lever-operated controls as well as Powered Up control for other functions. Features: Suspension Rear-Wheel Steering Drive 9-speed, 6-clutch nonsequential transmission Differential Lock Aesthetic: There isn't really an aesthetic, though I tried to keep the mechanical bits black, and the base is a constant LBG. Suspension: Perhaps I would have limited this model to a basic transmission demonstration, were it not for Koenigsegg's unusual triplex suspension design. Taking inspiration from previous Lego renderings of this design, I designed a suspension with hard shocks for each wheel, the central spring (heave spring?), and the Z-shaped anti-roll bar. Steering: Because the real car features rear-wheel steering, I did so too. There is a basic PF Servo design with a rack, with the motor being controlled by a PF switch connected to an external wheel. This switch is hooked up to the custom camera battery stuffed inside the PU hub. There is also castor angle and kingpin inclination. Drive: There is a hidden PF L-motor, controlled by a switch, like the steering motor, which runs the V8 piston engine and then the rear wheels, after passing through the transmission. Transmission: The transmission is naturally the highlight of this build, and aims to replicate the real car's complicated setup. The real car has six individual clutches, and is built in a 3x3=9 setup. There is then one clutch for each of the two sets of three gears, and because all the shifting is done by simply clutching and unclutching gears, without any mechanical setup, shifts can be wildly fast, and can jump from any gear to any other gear immediately. Additionally, there is a clutch to engage reverse, as well as a clutch controlling the rear differential, for eight clutches in all. In my simplified design, each side of each transmission driving ring acts as a clutch. The basic gearbox is, like the original, composed of two sets of three-speed gearboxes, with one also having an additional reverse gear, making it a 9+3R transmission (two Rs are ignored). I also connected a driving ring to the rear differential to simulate the locking of it, but in order to simplify design, it is connected to one of the other clutches through a linkage, such that the lock is always engaged in gears 1-3. This makes partial sense, given that slip situations in a car like this are most likely in hard launches, but is also kind of stupid in that most corners are taken in lower gears. I probably should have made an individual motor control it, but I didn't think of it in time. The shifting itself was controlled using all four of my PU motors, two Ls and two XLs, each one controlling one of the driving rings for the 3-speed and 3+R transmissions. With complicated programming, I was able to create a realistic control setup. This consisted of a 3x3 square of blank dots, which corresponded to gears 1-9 in the same pattern as my calculator. Beside this were three buttons with square symbols on them, controlling Park, Reverse, and Neutral. There was also + and - buttons to allow for sequential shifting through the gears, as well as a dial to indicate which speed was in use (1-9 for the normal speeds, and 17, 19, and 15 for P R and N, since they are the 17th, 19th, and 15th letters in the alphabet, respectively). This control allowed for shifting in both sequential and nonsequential modes. Of note is the Park setting, which engaged two gears at once on the output gearbox, locking the wheels, while leaving the input gearbox in neutral, so that the engine could continue idling, as in a real car. To really understand its operation, it is probably best to watch my video, below. Overall, this was quite an interesting model to build, and I liked the basic concept of building an interesting drivetrain without having to build a model around it. The Powered Up was also very cool to watch as it shifted very smoothly and reliably through gears, directly to any gear I selected. My images are at: https://bricksafe.com/upload

Is that even a PF train remote? It does look like one, but it has much more black on the front than is normal. Perhaps it is some chinese remote, or it simply has stickers or parts on top of it.

I was thinking it would be fun to build a true off-road bike too. If I try it, I'll think I will go with the "stuff-the-tires-with-marbles" strategy described in the RC Motorcycle thread. This should allow better stability at lower speeds.

That is a very impressive, complex model! I don't know if it would be possible in the context of your model, but replacing that twisted brown 5L with stop with a standard LBG 5L axle may make it stronger. Axles with stops seem, in my experience, to be much weaker than the stopless ones.

That is quite a clever design! There is obvious ingenuity in it!

Lookin' good! My sister adores Smart Cars, but I've never built one for her yet. Perhaps I could build yours to show her! I would recommend your option #2 as being the right balance of complexity and possibility, unless you could figure out a way to get the CVT to work. Perhaps just lowering the gear ratio from the transmission to the engine could work by reducing strain on the transmission?

Thanks for the explanation! That must have been a nightmare to "wire"!

That is a very nice, very well-thought out model! What do you mean when you say that you have seven pneumatic functions, manually selected between the three RC-controlled servos? My impression is that there are seven total functions, but the user must manually pre-select which three will be remote-controlled at a given time. Is this correct? How is this accomplished? I suppose this gearing to compensate for the wheel's diameters is not strictly necessary because of the presence of the central differential, but it does have the advantages of providing a 50:50 front-rear torque split, rather than a frontward torque bias due to the small wheels, and also reduces the amount of use (hence wear) on the central differential. I certainly wouldn't have bothered with that, but it is a nice touch!

That's really cool! Good job!

Yeah, that is the basic idea. That's quite a cool model, though it seems a shame that they had to resort to non-Lego electronics!

Well, according to Bricklink, the larger one is called Large, and the smaller one is called Small, and there isn't any one called medium, which seriously hurts my theory. Well, Lego did use the Mindstorms/Spike Prime Large angular motor in the Volvo hauler, so I don't see why they would mine using the small one in a different Technic set. As noted above, though, there really isn't any reason anymore to think it would be this one, though.

Those are really neat, and completely different from anything I have seen before in Technic! Good job!

It is well-established that heavier-than-air, pure Technic models cannot fly, and also that all Technic parts are heavier than air. However, a while ago I had the idea that it could be fun to make a light-as-air flying machine using helium balloons. The operating principle would be very similar to that of the Technic submarines that show up now and then, with the weight of the model carefully adjusted to counteract the lift of the helium balloons. Ideally, it would be tuned to the point that it would have almost the exact same density as air, causing it to remain at the same altitude it is placed in in the air, somewhat like a rather flat helium balloon. Once this equilibrium was set up, the model could be controlled using fans allowing control in X, Y, and Z axes, again, just like Lego submarines. Of course, this is not at all a true Technic flying machine, but I think it could be quite interesting to see. The only thing that prevented me from trying it originally was cost. My calculations suggested that a bare minimum of twenty balloons would be required to lift the model, and at $1 a piece, I was simply unwilling to throw that kind of money at an uncertain project, that wouldn't even last long until the balloons had leaked past the point of usability. Honestly, I'm really posting it in hopes that one of the more profligate of you users will give this idea a shot to see if it works! Anyways, that is my idea.

Let me add an option E. E. Perhaps the source confused the PU M-motor with the Medium Angular motor, as seen in the new Mindstorms set. The Volvo hauler showed that Lego doesn't mind putting angular motors in Technic sets, and this motor would be both Medium and have the position encoding. Of course, this is all rather wild speculation, but it is rather fun!

Yeah, the Defender rims look a bit modern for such a vehicle... Of course, you have no choice in an alternate model, and it otherwise is very appealing! Good job!

Ok, thanks!

I certainly hope that there will be a gearbox, as rumored, but I don't see how Lego would do it with an M-motor, since the current PU M-motor does not have the position encoding that would allow for more precise control, as in the Volvo hauler. If the rumor is true, I suppose we would need either A. A new M-motor with position encoding, B. A basic two-speed gearbox with a slip clutch and somewhat imprecise control, C. A fan-PF-model style four-speed that requires some skill to shift, which seems unlikely for Lego to do, or D. somehow the differential lock got confused with the gearbox. Probably option B. is the most likely, though A. would be the most exciting. Thanks for sharing this information, though!

I'm sure it would be easier, even base 6, 8, or 12 would work better, but I'd still like to keep the calculator in base 10, despite the difficulties. Thanks a lot! There are a lot of neat mechanisms that can (but rarely are) used in those 4-wheeled vehicles, but I finally realized that the (relative) pain of putting together bodyworks to cover the interesting mechanics was not an integral part of the Technic experience! The positive response to this model is encouraging me to try to develop my ideas further. I'm pretty sure I know how to remove one of the sets of buttons, and other desirable goals would be allowing for multiple digit numbers, and maybe even adding multiplying/dividing capability, though I don't really have any idea how to do that.

Thanks! This is by no means the first or best Technic calculator, though. This model of Nico71's, for example, looks quite impressive. I plan on building it soon to see how a master of Technic clockwork went about this idea! https://www.nico71.fr/mechanical-calculator-2/

Thanks! You're right that there aren't any zero buttons, but this is because the calculator assumes it is in zero unless something happens to change it. So basically, if I had a zero button, it would end up doing nothing whatsoever (unless I divided the 360 degrees into 11 equal parts, instead of 10, and added a N\A output as well. Also, in the original post, I neglected to mention the procedure for resetting the calculator. In order to do so, the motor had to be reversed, and then the two #9 buttons had to be pressed, engaging both axles and letting them rotate backwards until they hit the fixed stop, at zero.

I've been enjoying exploring various Technic mechanisms recently, rather than my usual car models, and thought it would be fun to try a mechanical calculator. I know some work has been done in this area by others, but for one reason or another, I tended to skip over reading about such models, so I'm not quite sure what is out there, or whether anything similar to this design exists. My design was meant to simulate a digital calculator, with buttons for various numbers, and a dial readout. Overview: In the end, there were twenty-one controls and three output dials. The first two controls were a simple on/off switch, and a lever to reverse the motor for run/reset capability. The third control is a +/- selector, to determine whether the calculator will add or subtract the two numbers. Finally, the last eighteen controls are the numbers, with the numbers one through nine repeated twice for the two input numbers. The dials included two small ones to display what the current input numbers are, and one large one to show the final answer of the calculations. Explanation: This explanation is probably not very clear, so you may want to just watch the included video! The calculator had a PF M-motor to drive it, powered from a rechargeable battery and an electrical switch. When running, it would default to not doing anything, and would merely run a number of 16T gears. There were two long axles with a transmission driving ring at one end, and a series of nine parts extending, at the closest approximations to 36 degrees I could get with Lego parts. Essentially, these parts were meant to be equally distributed around 360 degrees, with one gap where a tenth one could be put to complete the pattern. Above each of these nine protrusions, there were spring-loaded buttons, which when pressed did two things. First, they engaged the transmission driving ring so that the M-motor rotated that axle, and second, the button moved an axle into a position to stop the axle by bumping into a protrusion (The M-motor would continue trying to rotate the axle, but had a 24T clutch gear to prevent damage to the mechanism). Depending on which button was pressed, the axle would be rotated a different amount. If #1 was pressed, the axle would hardly rotate at all, while if #9 were pressed, the axle would be free to rotate all the way to a fixed stop, or about 324 degrees. The amount each axle rotated was fed to the dials for the input numbers, which read the same number as the button that was pushed. From here, the amount of rotation from each axle moved into an adder mechanism, using a differential. When in adding mode, the two axles drove the opposite sides of the differential in the same direction, causing the differential's output to be greater than it otherwise would have been. When in subtracting mode, the second input number's direction was reversed through a simple, low-backlash gearbox, causing the differential to effectively subtract the two numbers (or, as is perhaps more mathematically accurate, add a negative number). The differential's output, after some strategic gearing, ran the dial with all twenty-eight possible outcomes. In the end, the calculator was accurate to about +/- one number, due to backlash in the gearing. Other downsides were its inability to accept more complicated inputs, or to perform more complicated operations, but I think it is satisfactory for a first attempt. You can see my images at: https://bricksafe.com/pages/2GodBDGlory/mechanical-calculator

Six terminals! Wow! I previously proposed that a six-terminal PF-based system could have allowed Lego to keep the more flexible nature of PF, along with most of the motors, while still adding at least one "smart" servo. That's very interesting!

I too appreciate the all-black nature of the set, though I will say that building the model gave me a greater appreciation for the advantages of color-coding! Not that I would trade the all-black for anything else, though.

Here it is! It appears very stable in indoor tests, but my only worry is that the turning circle will be too large. Unfortunately, it is still raining outside, so more thorough testing will have to wait. EDIT: I got outside for tests, and they went well, with the only issue being that the sliding weights jammed up from time to time. I'm pretty sure this is due to grit from the road, so I'll have to see if the problem persists on drier road. Thanks for all the advice and inspiration!

That would be a good strong solution, but seems like it would be rather slow. I've had a productive morning, and my new bike is nearly done! All I really can think of to do is to add a stud to the front suspension to raise ground clearance enough for tighter steering. The balance is actually quite good with the PF rechargeable battery offset by one stud, and the sliding weights offset by one tooth of the gear rack. Hopefully I'll have something to show you soon!