Introduction: Micro Paper Robots (cyborg Crab)
Its a hexapod robot, its only a few millimeters high and its made almost entirely from paper !
Each of the mechanized insect's legs are fully articulated and it has the capacity to move at speeds of up to 240 steps per minute.
Once built this robot can move sideways much like a crab and the legs have a synchronized walking pattern thanks to the mechanism which I will explain in the instructable.
Also, this little creature is so small you can store it in a match box or even at the bottom of your pocket and although it is pretty fiddly to make once you get the hang of making them you can make yourself a swarm of miniature, paper robots!
Furthermore,because this robot is made only from paper and salvaged electronic components your robot army can cost you virtually nothing !
this project is very reliant on the correct dimensions and precisely cut components because it is so small and if there is even a slight error in the measurements the robot is liable to jam and stop working. I have reduced this problem for you by providing a template for the pieces however, take care when cutting. Also I used a pair of regularly shaped gears which I found ,when I tried to test, to be susceptible to jamming and so I will also detail how to make this robot using a worm drive which, according to my walking experiments, will mean far smoother mechanized walking.
-4 sheets of A4 paper/ 2 sheets of A4 card
-small motor (can be taken from old RC helicopters or bought from here :http://www.active-robots.com/motors-wheels/small-geared-motors)
-Use two LR44 button batteries if you want your robot to be self contained. If you want to hold a 9V battery while the robot runs along the ground this gives a much faster speed but doesn't look so great.
-small worm gear to fit the diameter of your small motor and an 8mm diameter gear with 18 teeth
-40 small pins
Step 1: The Blueprints and Templates
Print off the image of the different components onto either card or paper.
stick your card onto another sheet so it is double thickness, if you are doing this with paper you should make it 4 times the thickness.
now cut out the individual components and set them out as shown so that you don't get confused.
If you are doing the worm drive you don't need to worry about cutting out the ii) template because this will not be needed.
I used a sharp end of a paper clip to puncture holes in both the components. If you think you have cut these bits out inaccurately you should re-print and cut them because any distortion could lead to jamming.
Look at the top right hand corner to the thin shaped diagram, this will be the shape of your axle. Take a paper clip and bent it to this shape using a pair of pliers.
Step 2: Pinning the Bits Together
Firstly take your leg pieces and push a pin through the top hole, next slip on one of the 2nd largest attachment strips (attachment strips are the long thin shapes which you have cut out, image on the last step).
next take the longest attachment strip and feed the pin through the second hole now push onto the pin the smallest attachment strip.
now take this and pin it on the 3rd hole into the bottom hole of the leg. once you have finished leg mechanism you should take your super glue and glue the bases of the pins and leave to dry.
Once dry, using a pair of wire cutters cut off the pins as close down to the paper as you can, this is to avoid unnecessary abrasion on the other moving components.
The center legs have two legs on each side for stability when moving so according to the pictures do the same as above but with two legs together instead of one.
once you have three completed leg pairs place your bent paperclip through the 1st hole of each long attachment strip to ensure that it all can slip on and off with ease later on.
Step 3: Attaching to Center Plates and Testing Articulation of Legs
Now using the same system of gluing and cutting pin the attachment strips onto the center plates as shown in the pictures above.
To test the legs work: push the bent paper clip through the center hole in the plate and the two long attachment clips making sure that the attachment clips ore on an elevated section of the clip and the center plates are on the longer and lower parts of the bent clip now rotate the paper clip and as if by magic the legs will start to move in synchronicity and in a walking fashion.
Step 4: Inserting the Axle
push on the leg mechanism with double legs into the center of the axle (paper clip) and blue tack it down onto the side of a 9v battery (conveniently the correct width to slip between the legs and so helps stability when working on the robot)
again make sure that the attachment strips are on the slightly elevated bit in the center of the axle and the center plate is on the flat part of the axle.
If you are doing the worm drive (advised) don't bother putting on the second piece shown in the pictures.
Step 5: Attaching to the Base
Now stick down ,using superglue, your base (rectangle you printed out earlier) onto the bottom of your center plate. Stick the center plate onto the line 2nd in from the end.
Again using superglue attach your gear onto the axle directly on the other side of the center plate from the leg mechanisms. I have highlighted the correct positioning with a circle. leave to dry.
Now push on one of the other leg mechanisms onto the end of your axle,again, making sure that the two attachment points are on the elevated part and the main plate is not. stick using superglue this plate onto the base at the very end (the legs should jut out a little bit)
DOUBLE GEAR ONLY:
According to the photographs stick your remaining gear onto the motor axle.
then place the motor axle into the hole at the top of the center plate by cutting down a strip. now you can stick the bulk of the motor onto the motor mount plate. Make sure that the teeth are interconnecting before you stick everything down.
WORM DRIVE ONLY:
now for the fiddly part, you need to take your motor with the worm drive stuck onto its axle and stick the motor with heat resistant superglue vertically so that its worm gear is interlocking perfectly with your cog that you previously stuck onto the axle.
Sorry for the lack of photographs but I decided not to use the worm drive method for my robots because i) I lost my worm drive gear and ii) it is not as fast. But I advise using the worm drive because having done a number of experiments it is much less susceptible to jamming and if you make any minor errors it does not matter so much with the worm drive.
Almost there !
Take your last remaining leg mechanism and mount it onto the other end of the axle in the same way as you did with the other side.
Stick down, using superglue, this mechanism onto the base.
take your switch and solder it to one of the wires. If you cannot solder simply wrap this stripped end of the wire around one of the metal plates coming out from the switch. now take another length of wire and attach this to the other attachment point of the switch.
take your 2 button batteries and stick them to the top of the robot using superglue making sure they are touching each other (you can use velcro if you will want to replace the batteries)
now solder your wire coming from the switch onto the the top of one of the batteries and take the other wire and solder this to the bottom of the other battery.
You can now make whatever exoskeletons, coverings, decorations and armour that you would like and cover your micro crab.
I chose to make a segmented exoskeleton but,of course, out of paper and I highlighted the edges with black.
You now have a fully armoured, articulated robot hexapod made almost entirely from paper and about the size of a penny!
Time to get working on your swarm !