- In this tutorial, we will learn how to make a robotic hand. And how to controlled it.
- This video shows the low-cost "robotic hand" construction.
- You can learn a working principle of a robotic hand.
- We will control 5 servo motor robot hand with 5 pcs flex sensor.
- I created the flexible sensors myself.
- We will use external battery / power when doing this.
Step 1: Hardware Required
- Flex Sensor (5 pcs) '
I made the flex sensor myself'
- Arduino Board -Servo Motor (5 pcs)
- Foam (Like Styrofoam)
- Wires (Jumper) and Breadboard
- Battery and Battery Buckle
- Rubber Band
- Fishline or Wire
- Glue Gun and Utility Knife
Step 2: Make a Flex Sensor
Flex sensors are passive resistive devices that can be used to detect bending or flexing. The flex sensor shown in this tutorial is a flex sensor that decreases its resistance in proportion to the amount it is bent in either direction.You can easily make a sensor wider and longer depending upon your project.
- Flexible Cardboard or Plastic
- Aluminum Foil or Aluminum Tape
- Hot Silicone or Solder
A 2.2 inch flex sensor can range in price from $ 10 to $ 50.
If we think that at least 5 flex sensors are used in a robotic hand project, the cost will be quite high.
Step 3: Creating the Hand
- In the finger length, we cut the piece from the styrofoam.
- We divide the piece we cut into 3 parts like finger joints.
- We shape the sides of the square parts we cut with the help of sandpaper.
- We tie each piece together using rubber. We must leave some space between each piece.
- We drill all the pieces longitudinally with the help of a pointed rod.
- From these holes we pass the wire to the top of the finger. And let's take the knot to keep the wire stable.
- Let's cut a piece of foam as much as hand size.
Combine all fingers by hand.
Cut a piece of foam to mount the servo motors.
Connect all the finger wires to the servo motors.
Step 4: Creating the Glove
- You can use an old glove for this.
- We put the flex sensors we made on the glove fingers.
- We fixed with glue or cable ties.
- Note that you should not stick the sensors completely in the longitudinal direction. Intervals are good for comfortable movement of the sensor.
Step 5: Connection
- The external battery VCC / GND connect to the breadboard.
- The Arduino GND connect to the breadboard's GND input
- The servo connections we use in this project are as follows;
Orange Input - Signal Input
Red Input - Power Input (VCC)
Brown Input - Ground Input(GND)
- All servo motors VCC and GND connect to the breadboard's VCC / GND inputs.
- The signal inputs of all servo motors are connect to the Arduino Digital PWM 3-5-6-9-10 respectively.
- The sensors have two inputs. One is the GND line and the other is the signal (Analog) line. The signal line is connected to the VCC line by dividing with the help of a resistor.
Step 6: Code
- Get the Code (Only Copy and Paste)
- Add the Servo library
- Define Servos
- Define Flex Sensors
- Variable to read the values from the analog pin (flex sensors)
- Attaches our servos on pins PWM 3-5-6-9 to the servos
- Reads the value of flex sensors
- Scale it to use it with the servo (value between 0 and 180)
- Set the servo position according to the scaled value
- Upload the code