In this Instructable i will be going through an in depth description on how to build a robotic arm. This may seem like an intimidating project at first glance,but it is not too complicated, just a little bit tedious at times.
The robotic arm can be controlled by a controller that i show you how to make, or can even be controlled by a computer via an Arduino, which i will show how to do in a later tutorial.
To see how i create the arm and to see it's tests, you can check out the video
Step 1: Materials
The materials i used for this build were the various gears, large and small that are visible above. I also used 3 gearbox motors to drive various parts of the arm.
To build the body of the arm i used foam board and marked out the shapes of the parts i would use and then cut them out.
Step 2: Building the Base
To build the base of the mechanical arm, i start off by putting a hole in the center if the octagon and putting a piece of a straw in it. This will enable a dowel to rotate easily in hole. I then attach a motor with a gear and make sure it is in a position that it's gear can mesh with the dowel's gear. To complete it, i place on top another octagon with a hole in the middle. After that, the sides can be added to hold the top in place. The black circle added afterward is glued to the dowel so when the dowel rotates, the top circle rotates.
Step 3: Building the Arm
To make the arm i first glue two half circles to the rotating base. I put a hole in the half circles and put the dowel through them. I also secure a gear onto the dowel. After that i add two Styrofoam pieces and secure them to the axle to serve as the arm. The motor is put in last and secured to the base in an orientation so that it's gear meshes with the gear of the arm.
Step 4: Making the Claw
To make the Claw we first drill holes in the end of the arm , this will be where the gears will be mounted. After that i cut 4 pieces of Styrofoam into the shape of the claw. After that i cut one of the pieces in half and glue a Styrofoam piece onto each side of it so that one claw is 3 pieces thick. The other side of the claw is made up of one full piece. This design will allow the grabbers to mesh when they close. I Then put the dowels with gears through the holes and attach the arms to the dowels as well.
Step 5: Mounting the Motor
To mount the motor you cut a hole beside the gear and glue a small gear onto the motor. I then mount the motor into the arm so that the gears of the motor will mesh with the claw's gears.
Step 6: Making the Remote
To make a remote that can work in the forward and reverse direction i came up with an idea to implement it using household materials. I start off by pushing 4 pushpins with wires attached to them, into the top of a water bottle. I then chose 1 pushpin and the pin opposing it, and connect their wires to the pin located clockwise from them.
After that i add the lid onto the bottle and put 2 pushpins through it. The push pins have wires attached to them, those wires will go to the power source. In the 4th picture, a bottom view of the pins is visible. When the lid is turned until it touches one set of pins the motor attached will travel in a direction. When it is turned to touch the other set of pins the motor will go in the oposite direction
Step 7: Testing It Out
To add a final touch, i cover the wiring of the controller with construction paper. Now the arm and controller can be tested. After getting used to the controls, i found that i could pick up a bottle lid and and also pick up other small things like a roll of electrical tape and could even move it with enough precision to place one inside the other. To see the tests and the rest of my video check out my channel