Let's Make Robots!

Jansen Walker Toy (sized) Bot

Hello everyone,

This is my first post here, don't be rough.

I stumbled on the this site about a month ago while doing research on a bot i'm building that's similar to Rik's current Jansen Leg project, that's actually what I was searching for when I found the site.

Anyway, I wanted all of you input on my project, my version uses a similar leg design and I'm curently planning on powering it with two servos and an Arduino-clone.

 Leg-Pair-1-Animation_2.gif

I'm trying to decide on the size, either a medium sized bot that would be about 8 inches in height and width, or a tiny 3in version. There would be lots of space for sensors on the big one, very little space on the small one.

The obvious drawback to the big one is the cost of materials, it actually uses about 10x as much since the parts are bigger and thicker. The little one would be cheep to have cut, but would only have space for one or two small sensors.

I plan on making the plans publicly avalible to anyone that wants to build their own, which one would you like to see?

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.

Wow, some result for firing up a robot and waiting for the parts! That would have taken me a long night at the jig saw. I'm anxious to find out how your 3 mm bolts are working out for you. Did you ever consider smaller ones?

Did you consider lock nuts. I could not find any that small in my hardware store. Others have suggested liquid fastener for bolts. Brand names will vary.

I'm going to reserve final judgment on the 3mm bolts until I get the whole thing together, but my first impression is that they will work. I do need to find some kind of locking washer like you say, I was hoping that I would be able to get away with just tightening two bolts together, but it's not as easy as it seems.

Having the laser around is awesome for this kind of project, it really makes it easy to turn out prototypes. The downside is you have to spend a considerable about of time drawing all the parts in a CAD program first. I've found that SolidWorks is great for mechanical stuff, but has a pretty steep learning curve.

Don't worry about duplication. Not here on LMR. I am looking forward to updates on your project. At least provide us with (more) links to your (beautiful) blog.

I had to hit ESC on my keyboard to stop being mesmorized by the animated gif. Now I can type again.

And think.

I agree wit Mike and Oddbot. Size does matter. For example: in my experiments with pivots, I found that plywood of 3.6 mm is almost impossible to work with. The joints (pivots) would not be strong or durable or tight or simple. When I upgraded to 6 mm (and better quality) plywood, that problem dissappeared. I cannot imagine making my legs smaller with the same material. "The only way is up."

BTW, my legs now measure about 25 cm (10 inches) from the floor.

Turns out that the enabling technology for my vehicle is in the pivots. They now dictate the use of material and size of the whole machine. Or the other way around: the only thing I need to miniaturize my vehicle, is better a pivot technology. Or lower my expectations towards load bearing capacity...

I've got two basic choises with plexi-glass: 2mm which is only about $1.50(US) a perfectly sized sheet that I can stick right in my laser. The other is 6.5mm thick and costs about $20.00(US), but has to be cut down by hand into 6 peices to fit in the cutting area.

There's also a fiberboard wood that I've been toying with that's 3.5mm, but it's not as attractive as the acrlic. You can however get an 8x4 foot sheet that would make many robots for only about $10(US).

I guess either of those options won't break the bank, but I've been toying with the idea of selling inexpensive kits of the mechanical parts, I think that would be pretty cool.

Due to the complexity and effort involved in making the legs reguardless of size I would make it big enough for plenty of sensors and brains.

Why limit yourself to 3 or 8 inches? how about 6? that should be big enough for sensors and brains. 

I'd build the bigger one because:

a) My limited experience of robotics has shown me that construction material is far cheaper than electronics or drives

b) It's easier to work in a large space than a small space - so frustration will be lower

Reasons for a small bot are:

a) Small is cute - noise0 proves this again and again (although big is macho)

b) There's less mass to move so there might be big savings on the drive train