The Purple Robot and its Successor…
A few years ago, when I was at uni, my friend Reg and I were inspired by the Lynxmotion Hexapod 1 that featured on the cover of Silicon Chip magazine. So we got some second hand servos, cardboard, paper, hot glue, wire etc and made, over about three evenings, a working model of a 3 servo hexapod. I hooked the servos up to the parallel port of a pc and ran a program to send the pulses to them.
We didn’t get any photos of it in action, but I still have the ‘carcass’:
Toothpicks and rolled up paper formed the bearings, and it had a purple flag with a smiley face on it. 
Later I added bump switches and a Basic Stamp to give it a life of it’s own. Being cardboard though, it wasn’t built to last forever, and it was retired and rebuilt into a permanent home a few years ago.
And yeah, it is smiling!
The body is all aluminium, with steel wire linkages and screws/threaded spacers as bearings.
There’s not much program space in the basic stamp, just enough to make it walk around, bump into things and turn around. It also has red LED ‘eyes’ and a speaker. It’s main problem is the steel wire linkages – they tend to bend, causing the robot to drag its feet and turn to one side…
Hot glue and epoxy resin were used to mount the servos. Oh, and a cable tie. The main aluminium panel used to be a heatsink in an old TV or something. The top cover used to be a Jaycar blister pack, I warped it with heat from a candle, and painted it black. I really should name it something… Or perhaps I should repaint this one purple as well.
Well, that’s all for today.
Roland
Hehe it’s amazing what you can do with a couple of toothpicks and a little ingenuity!
Thanks for the inspiration to get off my arse and get all the parts I have laying around turned into a bot. I mean, you used a candle to warp the covering for your robot… If I can’t make something with my shiny new Dremel (which has only been used on some random plastic I had lying around) then it’s all over!
Also I am slowly coming to the realisation (after many years of exposure) that aquiring a hot glue gun should be my number one priority if I want to be successful in life. What can’t those guys fix?
You neeeeed a hot glue gun.
I convinced a friend of the advantages of hot glue a few years ago when he was trying to remove a peice of wood that Reg and I had previously hot glued to a metal chassis with the aid of a blowtorch to heat the metal. He was amazed at the strength of the bond.
Even my bicycle lights (microcontroller based) are held together and in some parts protected from the weather by ‘potting’ in hot glue.
So get out the junk box and start building!
Just don’t drip the glue on your leg…
Occupational Health and Safety laws require me to chip in here and say — don’t try to get the glue off, just have ice-cubes or at least a bucket of water handy when working.
And never, never, never try to pull a glue stick out the back of the gun.
Never.
Roland, I like your style.
Simple yet effective. yet stylish.
Still, way too small.
Why are ALL our robots so SMALL????
If you took any one of our robots and upsized by 4. WOW!!!
What about foam bots? Big but light. obviously mass and torque = requires power = requires batts and lektroniks = $$$ , but there must be a way ………………
aside………
I have a few old milk crates lying around. Wot about milk crate Borg bots – everything must fit within the profile of a milk crate and wheels strapped on???? bots designed to interact with other borg bots??? Everyone elses borg bot has different behaviours. Common linkage protocols. Let the borg collective assemble.
DaveyMilla.
p.s. I showed my housemate my wheel press that I had machine shop manufactured for omni wheel making. you put melted plastic in it and squish it. and hey presto – small plastic wheel. HE DROPPED IT. HE BROKE THE CENTRE PIN THAT PUNCHES THE AXEL HOLE!!!!!!
Because I like your mad at hoc robots roland, I shall now soon post some TESKI and OMNI pics. This shall involve non laziness. oh deaar!
Lay all your beer bot plans to bed boys, that show is already over!!! — (tongue in cheek!)
p.p.s I am into kite surfing. the latest new scientist has a snippet about some yank roboticist who has used neural networks to fly stunt kites!!! but if you stake the two lines apart it often flys stable figure 8 anyway!!!!
ppps. awesome band at pub !!! http://www.tobymusic.com.au – if I recall the blonde bombshells words — what a banshee!!!!!!!!!!!!
I am yet to use an old vertical blind on a robot.
Its mechanism has a single rotating shaft that connects to any number of sliding worm drives.
Each vertical blind ‘ribbon’ can be replaced by a wheel.
Each wheel mechanism can slide along the main shaft.
— make each wheel a leg ? —-
—- give each leg individual spring recoil? –
We have seasonal ‘chuck outs’ in perth. next time I see one of these sukkers in a pile of junk on the side of the road, its coming home with uncle angle grinder!!!!
DaveyMilla.
Sounds like we’ve both had our experiences with hot glue!
I think you already have the answer – mass–>trorque–>power–>larger batteries and electronics = more $$$.
Combined with the standard size of servos available for the radio control market, and perhaps the size of our garages/sheds/robot building rooms as well.
However, I did just buy a jumbo servo kit from Oatley Electronics – turns any large dc motor eg power window or wiper motors into a servo.
Maybe one day I’ll build a LARGE version of the three servo hexapod…
They’re called "scars", man,… scars.