Introduction: 3D Printed Robotic Hand With Arduino
This project is my personal way of completing the DIY Robotic Hand Controlled by a Glove and Arduino, by user dschurman. The link to his page is here.
Step 1: Gather Materials
4 MG946R Servos
4 4.5 Inch Flex-Sensors
1 Arduino Uno
4 22k Ohm Resistors
1 7.2V NiMh Battery 2-Pack
1 Tiny Breadboard
1 Battery connector
1 Small PCB
1 Right-Handed Glove
1 Bolt (8.00mm x 55mm)
1 Bolt (8.00mm x 60mm)
1 Bolt (8.00mm x 80mm)
14 Screws (3mm x 0.5mm x 20mm)
20 Screws (4mm x 0.7mm x 30mm)
1 Roll of Fishing Wire (I used this: https://www.amazon.com/SGT-KNOTS-Paracord-Type-Str...
And A LOT of Crimp Tubes.
Step 2: Print the Hand
All the parts can be found on this website: http://theroboarm.com/section1.html
Step 3: Test Flex Sensors
To test the flex sensors, I set up a sample circuit on a breadboard, and put in a code to test the Flex sensors. The code and a diagram of the circuit can be seen. The code is set up to use all four flex sensors at once, but can be used with one at a time. To use more than one flex sensor, just repeat the circuit.
Step 4: Assemble Hand
The next step I did was to assemble the hand. This is where you will use the screws. Notice, I did not put the servos into the base during this step. To do this, pull the pieces apart and screw each finger in, and I suggest putting the piece open on both sides on first. Make sure the screws are loose enough to allow the fingers to bend.
Step 5: Test the Servos
Before putting the servos into the base, I suggest testing them using the flex sensors and the code. The circuit can be seen above. Note: You can use a breadboard instead of a perfboard for this step, but you will want to use the perfboard once the servos are in the hand. If all of the servos rotate fine, you can put them into the hand. Otherwise, make sure all of the connections are in the right pins. When using all four at once, make sure to have a separate power source for the servos, and connect the grounds.
Step 6: Put the Servos in the Hand and Solder It
This step is putting the servos in the base of the hand. The wires go through the back and the bottom. The top servo does not go in as well as the other ones. Then the next step I did was soldering the connections for the flex sensors. Use the clips on the base of the flex sensors to protect the bases. To use the clips, cut the base off and clip them in. I used single-strand wire, which removed the need for tinning the wire.
Step 7: Fishing Wire
The next step is to set the hand up with the fishing wire. Feed the wire through the top and use crimps to hold the wire into the servos. This is the hardest step of the project, and will likely take you a little while, but it is almost done after this.
Step 8: Testing
Before sewing the glove, I recommend that you test the fingers work, so that you can be sure the hand works. Just hook the servos up to the flex sensors, and then run the program. Test all four fingers. NOTE: The fourth and fifth fingers move together.
Step 9: Set Up the Glove
The final step I did was setting up the glove. I recommend sewing the flex sensors on, but if you are like me, you will likely want to use something like electrical tape to hold the flex sensors on.