Sternford

With the hailfire wheels, how do they attach the wheels to the structure? I do not have any of the wheels, but from what I've seen there doesn't seem to be anything on the sides where you can connect them to anything.

That steering is pretty cool. I remember someone posting something about a vehicle that had the wheels in a position similar to the tumbler that could possibly use that mechanism.

A display where people are encouraged to put something in their mouth and then hand it off to the next person? The scorpion is quite funny though

Indeed, but only for the small one

It would probably be more practical if the gears had slightly different dimensions. The one 8 tooth gear is offset by something like a third of a stud

I stumbled on this page and thought I would try making a technic version for fun. It converts rotation into a linear back-and-forth motion. It's very jerky because there's a lot of backlash with the gearbox parts. Unfortunately it's pretty bulky too and in the end doesn't give very much movement. I started out making a bigger one with 40 and 20 tooth gears, but when I couldn't figure out how to make it work I made this one...And then after I had finished I realized how I could make the bigger one work. But I have limited parts and didn't want to take the small one apart. Any other neat methods for converting rotation to translation?

That planetary gearbox is really cool. I only have one of the old turntables, but I threw something together that works. If only I had something to use it for though

That is very cool. The legs look a bit unstable though, since they are only connected to the body on one side

Well the pieces I needed were finally delivered today so I was able to finish. Here's what I got It can't walk on carpet. Here's what one of the legs looks like. I didn't come up with the design, but I modified it to make it stronger. The design I based it on was supposed to be modular, but I made some changes to make it smaller that also make it a pain to take apart. This is two leg modules connect. The walker is made of two of these. When both sides walk in the same direction, it goes forward; when they walk in the opposite direction, it turns. In between the legs is the motor box thing. It is pretty heavy. This is what I finally settled on as the mechanism to drive the legs, using my new gear pieces. One motor wasn't strong enough to power it so I just put another one in. My solution to changing the gears. Originally, before my parts had arrived, I had designed something based on this, but as the person who made that noted, it took a lot of torque, and when today when I tried it my motor wasn't powerful enough. The whole thing is run off of one of the train speed regulators, so in order to go from walking to switching gears, you have to physically switch the wires. It's inconvenient, but not enough for me to care. It works pretty well, considering how heavy it is. I hope to get a video some time soon.

A ton more on this page, also with a lot of information on all the mechanisms and such. [edit] I just came across this in one of the guns, the description is "a transformer to convert two 9v inputs to one 18v output." Could be useful for other things, I dunno

The 8865 gearbox is what mine is based on. The gears kept not being lined up right when I tried to change functions

@allanp, that is a pretty interesting system, but I feel like I'd rather have the engine not move. I've set up a paypal account just so I could order the gearbox pieces (and some universal joints, because why not?). I hope within a week I will have them and can get it working

Efferman: Dang, I was afraid that those special gears would be the only way to do it. I wish I had them. Mortymore: I already have it so it can walk and turn, I guess I'll just live with having to manually fix the gears when they get stuck. And also, I though Sariel's ten speed gearbox was complex, but I guess it doesn't have reverse Telecasterman: It was done before this, I was just wondering if there was any way to fix this problem that didn't require the specially made gears. I tried to make legs myself but after a while of it not working looked around and went with this design. Apparently the problem was the legs I made didn't have the correct dimensions <object width="425" height="350"><param name="movie" value=" name="wmode" value="transparent"></param><embed src=" type="application/x-shockwave-flash" wmode="transparent" width="425" height="350"></embed></object>Thanks for replies [Edit]Oh! While I'm here. There's a weird thing happening with the pneumatics in the walker. I used Sariel's pneumatic autovalve so I would only need one motor to control that (It takes two motors to make the legs move or there isn't enough power). It works well, but for some reason, when I run the motor one direction, the piston moves very slowly. It is fine in the other direction though. Very odd.

For a week or so now I've been working on making a walker based on Theo Jansen's designs (Actually, after I couldn't get the legs right I based them off of someone elses' leg designs). After I made a simple four legged thing that just went forward and back, I wanted to make one that could turn and could be remote controlled. The problem is I just got back into technic after not touching legos for years (It was this project that brought me back), and I am very limited in the pieces I have. I have the mindstorms brain thing, but I'm not sure if I have the software to program it anymore, and either way I kind of decided that I would go without it anyway, kind of as a challenge. So I have three Mindstorms motors driven by one of the large controls for the lego trains and some pneumatics. The first and second pictures attached show the little gear box thing I came up with so the robot would be able to turn. The top gears in the second picture physically move forward and back to engage the gears in the first picture, giving two combinations, turning and straight. The gears are shifted by the piston in the third picture. And now my question. The main problem with this is that occasionally when I'm trying to shift the gears the top two will get caught on one of the bottom ones that are unaligned, which then causes the piston to just snap the part it's moving, or the motor running the piston will just fall off. I'm wondering if anyone knows of any way that could keep the gears aligned so they don't get stuck when they are moving. Hopefully there is a way that doesn't involved purchasing anything or using any unusual parts.