Robotic Hand Project

Background

The final project for the Mechatronics course I took in the spring of 2016 was to design, build, test and showcase a fully functional robotic hand. The objective of the project was to produce a hand or claw that would be able to hold soft objects, like toilet paper rolls, without crushing them while also being able to successfully grip relatively heavier objects without dropping them. My team and I had decided to go with a master-slave protocol where flex sensors, attached to a the fingers of a glove would dictate the movement of the corresponding fingers on the hand. Altogether, this an invaluable and rewarding experience that taught me much about designing and building a working product and how to apply control to that product through various forms of engineering.

Robotic Hand report FINAL.docx

The link to the left leads to an informal report on the hand project that details the design, construction, material specifications, mechanics, coding, and electronics that went into the production of our model hand.

Here is a link to the youtube video of me testing out the capabilities of the finished robotic hand.

Below are some photos and pictures from the report

Programming was done with an Arduino Uno microcontroller. Below is the code used on the hand

// Robot hand

// Include the servo library to add servo-control functions:

#include <Servo.h>

// Create a servo "object", called servo#. Each servo object

// controls one servo

Servo servo1;

Servo servo2;

Servo servo3;

Servo servo4;

Servo servo5;

// Define the analog input pin to measure flex sensor position:

const int flexpin0 = 0;

const int flexpin1 = 1;

const int flexpin2 = 2;

const int flexpin3 = 3;

const int flexpin4 = 4;

void setup()

{

// Enable control of a servo on pin 9-13:

servo1.attach(9);

servo2.attach(10);

servo3.attach(11);

servo4.attach(12);

servo5.attach(13);

}

void loop()

{

int flexposition0; // Input value from the analog pin.

int servoposition0; // Output value to the servo.

int flexposition1; // Input value from the analog pin.

int servoposition1; // Output value to the servo.

int flexposition2; // Input value from the analog pin.

int servoposition2; // Output value to the servo.

int flexposition3; // Input value from the analog pin.

int servoposition3; // Output value to the servo.

int flexposition4; // Input value from the analog pin.

int servoposition4; // Output value to the servo.

// Read the position of the flex sensor (0 to 1023):

flexposition0 = analogRead(flexpin0);

flexposition1 = analogRead(flexpin1);

flexposition2 = analogRead(flexpin2);

flexposition3 = analogRead(flexpin3);

flexposition4 = analogRead(flexpin4);

// map analogread's range to servo range

servoposition0 = map(flexposition0, 600, 900, 0, 180);

servoposition0 = constrain(servoposition0, 0, 180);

servoposition1 = map(flexposition1, 600, 900, 0, 180);

servoposition1 = constrain(servoposition1, 0, 180);

servoposition2 = map(flexposition2, 600, 900, 0, 180);

servoposition2 = constrain(servoposition2, 0, 180);

servoposition3 = map(flexposition3, 600, 900, 0, 180);

servoposition3 = constrain(servoposition3, 0, 180);

servoposition4 = map(flexposition4, 600, 900, 0, 180);

servoposition4 = constrain(servoposition4, 0, 180);

// Commands servo to move to position determined by flexor

servo1.write(servoposition0);

servo2.write(servoposition1);

servo3.write(servoposition2);

servo4.write(servoposition3);

servo5.write(servoposition4);

}