Automated Gantry Version 1.0 is complete

I am now deeming this stage that I'm at Automated Gantry Version 1.0. It can now carry out a storage and retrieval function and has all components connected and functioning. In saying this, everything is still too inaccurate for an inventory system so a the moment the storage and retrieval works off an input coordinate, not an item number input. This requires will require more consistency, which cannot be achieved by lego. In addition to that, the teethed pulley hub which was 3D printed was not printed accurately enough to get maximum grip to the timing belt. Thus to get the right tension to make it work, I had to make the x axis longer  using lots of tape to hold it in place. I was in a rush because I had to get the prototype submitted the next day for school.

Flaws exist but nonetheless the robot does function decently where it is at now. A video of this is below consisting of scenarios each at a different angle of the store function being run (to coordinate 15,5), a home function being run (so the robot has to move back to the start position, otherwise it'll just go down and pick up straight away which is no fun), and then the get function (back to coordinate 15,5).

Images of the physical changes and current state are below (The little blue thing is a blue lego brick with a piece of thin steel double sided taped to it. This is meant to represent the fridge).

Aside from the physical updates the code has also changed. On top of a few small value tweaks, a store and get function have been added. These right now run off a coordinate following the function. Eg store 18 3. The other change is that now upon start up, the robot will run routines servo up and home so that it will automatically reset its position to 0,0.

The new code is below:

	#include <Wire.h>
	#include <Servo.h>
	int Xdir=6; // drive pin to X direction relay
	int Ydir=4; // drive pin to Y direction relay
	int Xenable=5; // drive pin to X enable relay
	int Yenable=10; // drive pin to Y enable relay
	int Xpulse=3; // input from X encoder
	int Ypulse=2; // input from Y encoder
	int Solenoid = 9;
	int Xhome = 11;
	int Yhome = 8;
	boolean Xdirection=false; // true if motor forward / false if reverse
	boolean Ydirection=false; // true if motor forward / false if reverse
	Servo Lift;
	int Xposition=0; // encoder count for X
	int Yposition=0; // encoder count for Y
	boolean Xtravel = false;
	boolean Ytravel = false;
	int OldXstate, OldYstate; // input state of encoder pins (HIGH,LOW)
	String inputString = "";
	boolean stringComplete=false;
	String cmd = "";
	int arg [4] = {0,0,0,0};
	int ArgIndex;
	void setup()
	{
	Serial.begin(9600);
	Serial.setTimeout(2);
	inputString.reserve(200);
	Serial.println(" Automated Gantry Warehouse");
	pinMode(Xdir, OUTPUT);
	pinMode(Ydir, OUTPUT);
	pinMode(Xenable, OUTPUT);
	pinMode(Yenable, OUTPUT);
	pinMode(Solenoid,OUTPUT);
	pinMode(Xpulse,INPUT);
	pinMode(Ypulse,INPUT);
	pinMode(Xhome,INPUT);
	pinMode(Yhome,INPUT);
	digitalWrite(Solenoid,LOW);
	Lift.attach(7);
	Lift.write(128);
	OldXstate = digitalRead(Xpulse); // get state of encoder inputs
	OldYstate = digitalRead(Ypulse); // ...
	ServoUp();
	GoHome();
	}
	void loop(){
	// readY();
	// serialEvent();
	CheckEncoders();
	if (stringComplete){
	HandleCommand();
	inputString="";
	stringComplete=false;
	}
	}
	void Home(){
	MoveTo(0,0);
	}
	void MoveTo(int x, int y){
	// if ((x < 0) || (y < 0) || (x > 40) || (y > 40)){
	// Serial.println("XY commands out of bounds");
	// return;
	// }
	Serial.println(y);
	if (x !=Xposition){
	if (x > Xposition) XForward();
	if (x < Xposition) XReverse();
	}
	while (Xposition !=x){
	CheckEncoders();
	ShowEncoders();
	}
	XStop();
	ShowEncoders();
	delay (1000);
	// return;
	// ShowEncoders();
	// delay (2000);
	if (y != Yposition){
	if (y > Yposition) YForward();
	if (y < Yposition) YReverse();
	}
	ShowEncoders();
	while (y !=Yposition){
	CheckEncoders();
	ShowEncoders();
	}
	YStop();
	ShowEncoders();
	}
	void PickUp(){
	MoveTo(arg[0], arg[1]);
	}
	void GetFridge(){
	MoveTo(arg[0],arg[1]);
	ServoDown();
	delay(400);
	SolenoidOn();
	delay(300);
	ServoUp();
	delay(200);
	GoHome();
	ServoDown();
	SolenoidOff();
	delay(200);
	ServoUp();
	}
	void StoreFridge(){
	GoHome();
	ServoDown();
	delay(200);
	SolenoidOn();
	delay(300);
	ServoUp();
	delay(200);
	MoveTo(arg[0],arg[1]);
	ServoDown();
	SolenoidOff();
	delay(400);
	ServoUp();
	}
	void GoHome(){
	if (digitalRead(Xhome) == HIGH) {
	XReverse();
	while(digitalRead(Xhome) == HIGH){
	CheckEncoders();
	}
	XStop();
	// Xposition==0;
	}
	if (digitalRead(Yhome) == LOW) return;
	YReverse();
	while(digitalRead(Yhome) == HIGH){
	CheckEncoders();
	}
	YStop();
	// Yposition==0;
	ResetEncoders();
	}

view raw Automated Gantry hosted with ❤ by GitHub

	void HandleCommand(){
	ParseInput();
	if (cmd == "xf") XForward();
	if (cmd == "xs") XStop();
	if (cmd == "xr") XReverse();
	if (cmd == "yf") YForward();
	if (cmd == "ys") YStop();
	if (cmd == "yr") YReverse();
	if (cmd == "se") ShowEncoders();
	if (cmd == "xy") PickUp();
	if (cmd == "re") ResetEncoders();
	if (cmd == "servo") DriveServo();
	if (cmd == "solon") SolenoidOn();
	if (cmd == "soloff") SolenoidOff();
	if (cmd == "home") GoHome();
	if (cmd == "sw") ShowSwitches();
	if (cmd == "su") ServoUp();
	if (cmd == "sd") ServoDown();
	if (cmd == "get") GetFridge();
	if (cmd == "store") StoreFridge();
	}
	// from the serial input separate all arguments
	void ParseInput(){
	Serial.println(inputString);
	int space, slash;
	for(int x = 0; x < 4; x++){ // flush the last args
	arg[x] = 0;
	}
	ArgIndex = 0; // reset number of args to zero
	space=inputString.indexOf(' ');
	slash = inputString.indexOf('\n');
	inputString = inputString.substring(0,slash);
	cmd = inputString.substring(0,space);
	inputString = inputString.substring(space+1,slash);
	while (inputString.indexOf(' ') > 0){
	space = inputString.indexOf(' ');
	arg[ArgIndex] = inputString.substring(0,space).toInt();
	inputString = inputString.substring(space+1,inputString.length());
	ArgIndex++;
	}
	arg[ArgIndex] = inputString.toInt();
	}
	void serialEvent(){
	// Serial.println("l");
	while(Serial.available()){
	// Serial.println("d");
	char inChar=(char)Serial.read();
	inputString += inChar;
	// Serial.println(inputString);
	if(inChar=='\n'){
	stringComplete=true;
	// Serial.println("complete");
	}
	}
	}

view raw Commands hosted with ❤ by GitHub

	void ReadY(){
	//Y = digitalRead(Ypulse);
	}
	void CheckEncoders(){
	int X,Y;
	X = digitalRead(Xpulse);
	Y = digitalRead(Ypulse);
	// Serial.print(Xposition);
	// Serial.print(" ");
	// Serial.println(Yposition);
	// delay(200);
	if (OldXstate == LOW){
	if(X ==HIGH){
	if (Xdirection) Xposition++;
	if (!Xdirection) Xposition--;
	OldXstate = X;
	goto CheckY;
	}
	}
	if (OldXstate == HIGH){
	if (X == LOW){
	if (Xdirection) Xposition++;
	if (!Xdirection) Xposition--;
	OldXstate = LOW;
	}
	}
	CheckY:
	if (OldYstate == LOW){
	if(Y ==HIGH){
	if (Ydirection) Yposition++;
	if (!Ydirection) Yposition--;
	OldYstate = Y;
	// Serial.println(Yposition);
	return;
	}
	}
	if (OldYstate == HIGH){
	if (Y == LOW){
	if (Ydirection) Yposition++;
	if (!Ydirection) Yposition--;
	OldYstate = LOW;
	// Serial.println(Yposition);
	}
	}
	}
	// used in serial to show encoder counts
	void ShowEncoders(){
	Serial.print("X= ");
	Serial.print(Xposition);
	Serial.print( " Y= ");
	Serial.println(Yposition);
	}
	void PrintPosition(){
	Serial.print(Xposition);
	Serial.print(" ");
	Serial.println(Yposition);
	}
	void ResetEncoders(){
	Xposition = 0;
	Yposition = 0;
	Serial.println("Encoders reset");
	}

view raw Encoders hosted with ❤ by GitHub

	void SetXForward(){
	digitalWrite(Xdir,HIGH);
	Xdirection= true;
	}
	void SetXReverse(){
	digitalWrite(Xdir,LOW);
	Xdirection = false;
	}
	void XForward(){
	Xdirection=true;
	digitalWrite(Xenable,LOW);
	delay(30);
	digitalWrite(Xdir,HIGH);
	digitalWrite(Xenable,HIGH);
	}
	void YForward(){
	Ydirection=true;
	digitalWrite(Yenable,LOW);
	delay(30);
	digitalWrite(Ydir,HIGH);
	digitalWrite(Yenable,HIGH);
	}
	void XReverse(){
	Xdirection=false;
	digitalWrite(Xenable,LOW);
	delay(30);
	digitalWrite(Xdir,LOW);
	digitalWrite(Xenable,HIGH);
	}
	void YReverse(){
	Ydirection=false;
	digitalWrite(Yenable,LOW);
	delay(30);
	digitalWrite(Ydir,LOW);
	digitalWrite(Yenable,HIGH);
	}
	void XStop(){
	digitalWrite(Xenable,LOW);
	digitalWrite(Xdir,LOW);
	Xtravel = false;
	}
	void YStop(){
	digitalWrite(Yenable,LOW);
	digitalWrite(Ydir,LOW);
	Ytravel = false;
	}
	void Test(){
	XForward();
	delay(1250);
	XStop();
	delay(1000);
	XReverse();
	delay(1250);
	XStop();
	delay(1000);
	YForward();
	delay(500);
	YStop();
	delay(1000);
	YReverse();
	delay(500);
	YStop();
	delay(1000);
	}

view raw Motor Control hosted with ❤ by GitHub

	void DriveServo(){
	Lift.write(arg[0]);
	}
	void ServoDown(){
	int x;
	for(x=70;x < 134;x++){
	Lift.write(x);
	delay(20);
	}
	}
	void ServoUp(){
	int x;
	for(x=134;x > 71; x--){
	Lift.write(x);
	delay(20);
	}
	}

view raw Servo hosted with ❤ by GitHub

	void SolenoidOn(){
	digitalWrite(Solenoid,HIGH);
	}
	void SolenoidOff(){
	digitalWrite(Solenoid,LOW);
	}

view raw Solenoid hosted with ❤ by GitHub

	void ShowSwitches(){
	/*
	if (digitalRead(Xhome) == LOW)
	Serial.println("X is home");
	else
	Serial.println("X is NOT home");
	if (digitalRead(Yhome) == LOW)
	Serial.println("Y is home");
	else
	Serial.println("Y is NOT home"); */
	Serial.println(digitalRead(Xhome));
	Serial.println(digitalRead(Yhome));
	}

view raw Switches hosted with ❤ by GitHub

	void readY(){
	Serial.println(digitalRead(Ypulse));
	}

view raw Test hosted with ❤ by GitHub

Whilst blogging this, I have only been producing documentation for my IPT project. The user manual for this version as well as a few diagrams are below:

USER MANUAL:
Manual Control: This is done by use of a number of in-built commands stored in an array. When these commands are entered into the serial input, they will execute a routine which is assigned to that command and perform an action. These are in the table below (“ “) means a value must be written).

Command	Routine	Function
xf	XForward()	Move X-axis forward
xs	XStop()	Stop X-axis movement
xr	XReverse()	Move X-axis backwards
yf	YForward()	Move Y-axis forward
ys	YStop()	Stop Y-axis movement
yr	YReverse()	Move Y-axis backwards
se	ShowEncoders()	Print the current coordinates (in the form “x” “y”)
re	ResetEncoders()	Reset the coordinate value to 0,0
xy “ “ “ “	PickUp()	Move to the written x (input value in first “ “) and y coordinate (input value in second “ “) IMPORTANT: Only values between 0 and 20 for x axis. Only values between 0 and 10 for y axis.
servo “ “	DriveServo()	Move servo to position “ “. This lowers and raises the electromagnet (The Z-Axis) IMPORTANT: Only values between 60 (highest point) and 230 (lowest point) should be inputted.
solon	SolenoidOn()	Turn electromagnet on.
soloff	SolenoidOff()	Turn electromagnet off.
home	Home()	Move x and y axis back to starting position (0,0)

Automated Control:

Storing:

To store an item, you must tell the robot through the serial monitor input that you have an item in the docking bay which must be stored. To do this we enter the command Store. This tells the robot that it is going to the docking bay, and storing an item in an available space.

However, in accordance to the old layout of storage, each row will be dedicated to a certain model of fridge or freezer. Thus, you must also tell the robot, what row and column the fridge is being stored. This can be done by adding a space and then inputting an x y coordinate after.

The final resulting input line could for example be:

Store  15 6

Once this is typed into the input, press enter on the keyboard or click send to initiate the command. From here, the robot will complete the storing process.

Retrieving:

The retrieving process is conducted almost exactly the same as the storing process. Instead of the store command being typed into the serial input, type Get. This will tell the system it must retrieve an item and bring it back to the docking bay. However, you also need to input which model you wish to retrieve. To do this after a space, type the x y coordinate of the item you wish to retrieve.

The final resulting input line could for example be:

Get 15 6

Once it is typed, press enter or click send to start the retrieval. From here the robot will do everything else. 

CONTEXT DIAGRAM:

BLOCK DIAGRAM:

MASTER CIRCUIT:

The robot still hasn't got all the functionality I wanted so this Sunday I will begin the making of version 2.0. This will most probably have the exact same hardware and circuitry (possibly a few modifications) but will most significantly have a new structure built out of aluminium with the perfect tension for the timing belts and an inventory function which works off an item's stored location not a coordinate.