In this instructable I gonna try to describe how to make a robotic arm with parts from a printer, and control it using a NES gamepad.
It may look like a hard work but I have prepared templates for all the parts and I try to take pictures for all the angles in order to make it simple.
Also it is a really cheap robot, most of the parts come from a dead printer.
I used two PIC16F628A microcontrollers because only one was not enough for all the motors, they are pretty cheap and easy to get instead of a PIC with more pins.
Age group: only me:18+.
Step 1: Tools and Materials
Not many tools are required, a rotary tool is perfect for cut the metal and the plastic, also if you have a driller it could help with all the holes that you have to do.
For the electronics boards you will need a 30w soldering iron.
Most of the stuff come fron a dead printer HP660, other models of the printer like the HP670 are almost the same and will be fine. The things you must take from the printer are detailed in the next step.
For controlling the robot I use a regular Nintendo Entertainment System gamepad, it is not an original gamepad, any kind will work, and it is not hacked at all, you won't need to modify it to work with the robot.
From another printer you need the stepper motor that is attached to the belt, because the HP printer use a DC motor for this and they are harder to control.
Three plastic gears are required, two of the same size and one smaller.
The servo in the hand was broken so y took the wires directly from the motor and control it as a regular dc motor.
A block of plumb for using as counterweight, if you cant get one of these you can replace it with any other heavy thing.
Electronic stuff for the boards are detailed in step 11.
Wood: one piece of 54x16 cm, one piece of 11x11 cm and four pieces of 2x3 cm.
Aluminium: one bar of 8 cm and one bar of 20cm
Step 2: Stuff From the Printer
I used almost everything from the printer.
The plastic and the metal is used to make the plastics/metal parts.
There are 3 motors, 2 steppers and a DC motor, I just used the steppers ones with the gears attached to them.
I also used the cooper rings and the guide of the cartridge.
From the part that moves the paper I cut the first part with the metal gear and the center of the wheels.
Also all the screws can be used in the wood.
Finally take from the printer belt and the small plastic wheel where it rolls.
Step 3: Small Metal Parts
For making this parts I have recycled the metal core of a transformer.
Cut the templates and draw it above the metal. Cut and drill the metal.
Don't forget to paint it for avoiding the corrosion.
Step 4: Big Metal Parts
Like the step before I use the templates for cutting the metal but this time the metal have to be stronger. The metal of the chassis of the printer will be great for this.
There is only one piece that is welded. Since I have no soldering tools I send it to a workshop. It is just a small welding so they did it for free.
Remember that you have to paint all this parts too.
Step 5: Plastic Parts
For making the plastics parts you have to find straights parts on the plastic of the printer and cut them from there using the templates.
There is just one part that is critical and have to be done carefully. This is the one where the big stepper motor is attached. You have to cut it without avoid the bearer of the plastic gear.
Step 6: Making the Wooden Base
Nail two of the small wood on one side of the base.
Then measure the length of the guide and nail the other two.
Polishing the ends of the guides and screw them in the small wood. You can use the screws of the printer.
Ensure that the distance between the guides is slightly larger than the size of the base of the robot.
Step 7: Assembling the Hand
Take two of the plastic parts labeled P1 and glue one in the bottom and one in the top of one of the big plastic gears. Be sure that you are gluing in the center of the gear.
Repeat it with the other gear. The small one is glued in the servo.
Then take other two P1 and screw them to this.
Put this parts together and measure the distance between the center of the gears. Now you know where you have to drill in the P4 and P5 parts and join them using a small plastic spacer.
Now drill the holes for your servo and finish the assembly of your gripper.
Step 8: Assembling the Elbow
Start screwing together the M1 and M5 metal parts and then the small stepper motor from the printer.
Use the two M3 parts to attach the black plastic gear that come with the stepper motor with the M2 part.
Pass a shaft through the black gear and the holes of the M1 and screw it to the aluminum in order to finish this section.
Step 9: Assembling the Shoulder
Start putting together the plastic tubes with the welded part and srew it in one side of the wood. Then insert the metal gear inside of the plastic tubes and fix it with a screw in the end.
Now you have to measure how tall is it and make two custom metal parts in order to attach the big stepper motor to the metal gear.
Put the P3 parts in the back of the wood.
Attach your counterweight to the end of your aluminium and screw it to the shaft of the metal gear using the P2 parts from the top and a metal rod from the bottom.
Step 10: Final Assembly
Install the motor and the wheel of the belt. The motor should be at the beginning of the horizontal guides and the wheel should keep the belt straight.
Put the back of the arm in the guide of the back and secure the front to the cooper tubes using two plastics zips.
Using a small piece of metal attach the belt to the arm.
Step 11: Electronic Boards
1 bridghe rectifier
3 10k resistors
2 4k7 resistors
2 1k resistors
1 nes gamepad connector
2 100nf capacitor
1 100uf capacitor
1 12 volt 2 ampere power suply
I made the boards using the ironing method, the small one could be done from a regular bread board. The small board works as a stepper motor driver and is connected to the main board.
Step 12: Programming
For programing the PICs I used a JDM programmer and the WinPic 800 software. The hex file called Main is for the pic in the main board and the one called Aux is for the small board.
Step 13: Running
This robot is really easy for control, and probably is not the first time you use a NES gamepad.
We use A and B buttons for opening and closing the hand. Left and Right button for horizontal movement.
For the vertical movement we have two motors but one up button and one down button, so I decided to use the select button to switch between them.
Take a look at the videos if you have any doubt.