Bionic Finger



Why we need bionic limbs

Bionic limbs are important for people with amputations. It can give the person with the amputation the ability to do things that they would not be able to to do otherwise.

As a result of a bionic limb, the amputee will likely be less reliant on other people and will become more self-sufficient and able to help themselves.

Prior to bionic limbs, people with arm amputations would have used basic prosthetics. For example, an early version of the prosthetic arm would have been a wooden limb with a hook on the end.

However, with new bionic limb technology, the amputee will be able to do simple tasks, such as put a piece of toast on and pick up a water bottle with their new arm, without the assistance of other people. With this technology, amputees may be more confident and independent to carry out everyday tasks, they will not have to worry about regularly asking people to do things for them.

Being able to do this will give the amputee a sense of normalcy, also allowing them to have more freedom in their choices, this is why bionic limbs are important for people with amputations.
Components to make a bionic finger:

What the main components do:

Flex Sensor:
When bent there is resistance in the ink within the sensor. This sends message a to the Arduino board. In this task, the flex sensor, will be attached to a finger and send signals to the micro servo to mimic the movement of the finger.
flex-sensor

Micro servo:
Is an electric motor that runs backwards and forwards, in this task it will be pulling the fishing wire that is attachted to the 3D printed finger allowing it to bend.
micro-servo

Arduino board:
The control panel that holds the code and sends the signals from the flex sensor to the micro servo. For this task you will use a Arduino Nano.
arduino-board

Arduino app:
The code will be inputed into the app and then uploaded on to the arduino board.
arduino-app

Other components:
The remaining items being; Cable to connect Arduino board to computer, 3D printed part of the finger, Wood board, Fishing wire, Plastic strip, Glove or masking tape or elastic bands, Computer and Battery are the required parts to build the bionic finger.


Assembling the finger:
  1. Cut the plastic in to 4 strips into roughly 2cm long each
  2. Insert 2 of the plastic strips into either end of 2 parts of the finger to make joints
  3. Hot glue these parts together
  4. Repeat steps 2 and 3 with the other 2 plastic strips and 3D printed fingers
  5. Thread the fishing wire through the holes in the finger
  6. Attach the mirco servo to the to pin 9 and have brown to ground on the arduino board
  7. Attach the Flex Sensor to A0 on the Arduino board
  8. Thread the fishing wire into the micro servo
  9. Hot glue the Micro Servo onto the wooden board
  10. Plug the Arduino into the computer and upload the code that is on the 'Code & troubleshooting' page
  11. Attach the Flex Sensor on to the glove or tape it to your finger
  12. Attach the battery or use laptop power
  13. Test to see if finger works
It should look something like this:
finger
Code for Arduino:

#include angle-bracket Servo.h angle-bracket

Servo myservo;

void setup() {
myservo.attach(9);
pinMode(A0, INPUT_PULLUP);
Serial.begin(9600);
}

void loop() {
int flexSensor = analogRead(A0);
int angle = (flexSensor - 50`````````````````0);
Serial.println(angle);

myservo.write(angle);
}

Video to understand the code:


Troubleshooting:

From personal experience sometimes the processor and/or the port needs to changed. If the code won't upload try changing the processor to ATmega328P (Old Bootloader) as shown here:
old-boot

If it still doesn't work also change the port to /dev/cu.Bluetooth-Incoming-Port as shown here:
bluetooth