This repo includes Cankut Bora Tuncer's EEE212 2021 Term Project Multipurpose Wifi Camera Tank MUWCAT📌. This project contains two main parts: Software💻 and Hardware⚙️. For the software it is mainly used C language📌. The main code resides at KL25Z Freedom board📌. ESP32 communicates with the mobile app (wifi) and KL25Z (UART)📌. With the mobile app the user can control the 2 12V DC motors and 5 5V servo motors📌. Moreover, ESP32 sends the camera feed to the mobile app where the video can be seen📌. Last but not least, an Arduino Nano is used for initiating the QC3 handshake used in power banks📌. Feel free to contact me via email bora.tuncer2002@gmail.com for further questions📌.
- Cankut Bora Tuncer - Github
- Cankut Bora Tuncer - LinkedIn
- Cankut Bora Tuncer - Project Video Youtube
The KL25Z Freedom Board is coded with Keil uVision 5 environment. As for ESP32 and Arduino Nano, the Arduino Programming Environment is used. Mobile App is created on MIT App Inventor. The software part of this project can be divided into 4 parts:
📍 KL25z Freedom Board Programming
📍 ESP32 Programming
📍 MIT App Inventor Programming
📍 Arduino Nano Programming
The brain of the project resides at the Kl25z Freedom Board. It communicates with the ESP32 and drives the DC and servo motors.
The main program is quite simplistic. The code is written in an interrupt fashion for portability. In the main program, only the initialization occurs and waits for the UART interrupt.
int main(void){
WDT_init(); // Watchdog init
Systick_init(); // Systick init
__enable_irq(); // Enable interrupts
PWM_init(); // PWM init
motor_init(); // Motor init
UART_init(); // UART init
while (1){
Service_COP_WDT(); // Service the watchdog
}
}void UART_init(){
int divisor;
int temp;
SIM_SCGC4 |= SIM_SCGC4_UART0_MASK; // Enable clock to UART0
SIM_SOPT2 &= ~SIM_SOPT2_UART0SRC_MASK; // Clock source selection
SIM_SOPT2 |= SIM_SOPT2_UART0SRC(1);
divisor = (DEFAULT_SYSTEM_CLOCK / 115200 ) / 16; // BAUD rate calculation
SIM_SCGC5 |= SIM_SCGC5_PORTA_MASK; // Turn on clock to A module
PORTA_PCR1 = PORT_PCR_MUX(2); // Set PTA1 to mux 2 [TX]
PORTA_PCR2 = PORT_PCR_MUX(2); // Set PTA2 to mux 2 [RX]
UART0->C2 &=~ (UART_C2_TE_MASK | UART_C2_RE_MASK); // Register configuration
UART0->C1 = 0;
temp = UART0->BDH & ~(UART_BDH_SBR(0x1F));
UART0->BDH = ( temp | UART_BDH_SBR(((divisor & 0x1F00) >> 8)) );
UART0->BDL = (uint16_t)(divisor & UART_BDL_SBR_MASK);
UART0->C2 |= (UART_C2_TE_MASK | UART_C2_RE_MASK);
NVIC_SetPriority(UART0_IRQn, 2); // Mid Level Priority for UART Interrupt
NVIC_ClearPendingIRQ(UART0_IRQn); // Clear UART Interrupt Requests
NVIC_EnableIRQ(UART0_IRQn); // Enable UART Interrupt
UART0->C2 |= UART_C2_RIE(1); // Start UART
} void UART0_IRQHandler(void){
if ((UART0->S1 & UART_S1_RDRF_MASK)) // Check the reciever flag
{
Service_COP_WDT(); // Service watchdog
serial_rx = UART0->D; // Save the UART data
instruction_parse(serial_rx); // Send the data to instructon parser
}
}The first 3 bits from left contains the insturction, the other 3 contains the data.
void Instruction_parse(int rx){
int inst, data;
inst = (rx & 0xE0)>>5; // Masking the instruction
data = (rx & 0x1C)>>2; // Masking the data
switch(inst){
case 1: // Motor Direction
motor_direction = data;
Motor_drive(motor_direction, motor_speed);
break;
case 2: // Claw
Servo_drive(4, data);
break;
case 3: // Neck
Servo_drive(2, data);
break;
case 4: // Ankle
Servo_drive(3, data);
break;
case 5: // Knee
Servo_drive(6, data);
break;
case 6: // Bottom
Servo_drive(5, data);
break;
case 7: // Speed
motor_speed = data;
Motor_drive(motor_direction, motor_speed);
break;
default:
return;
}
}void PWM_init(void){
int x;
SIM->SCGC5 |= 0x1000; // Enable clock to Port D
PORTD->PCR[0] = 0x0400; // Configuring PTD-0 Mux (TPM0)
PORTD->PCR[1] = 0x0400; // Configuring PTD-1 Mux (TPM0)
PORTD->PCR[2] = 0x0400; // Configuring PTD-2 Mux (TPM0)
PORTD->PCR[3] = 0x0400; // Configuring PTD-3 Mux (TPM0)
PORTD->PCR[4] = 0x0400; // Configuring PTD-4 Mux (TPM0)
PORTD->PCR[5] = 0x0400; // Configuring PTD-5 Mux (TPM0)
SIM->SCGC6 |= 0x01000000; // Enable clock to TPM0
SIM->SOPT2 |= 0x01000000; // Clock source selection
TPM0->SC = 0; // Disable timer
TPM0->CONTROLS[0].CnSC = 0x20 | 0x08; // Center-aligned, non inverted
TPM0->CONTROLS[1].CnSC = 0x20 | 0x08;
TPM0->CONTROLS[2].CnSC = 0x20 | 0x08;
TPM0->CONTROLS[3].CnSC = 0x20 | 0x08;
TPM0->CONTROLS[4].CnSC = 0x20 | 0x08;
TPM0->CONTROLS[5].CnSC = 0x20 | 0x08;
// Initialize the servos
Servo_drive(5, 2); // Bottom
Servo_drive(6, 0); // Knee
Servo_drive(3, 0); // Ankle
Servo_drive(2, 2); // Neck
Servo_drive(4, 0); // Claw
}
} The servo drive function drives the servos according to the incoming data from UART
void servo_drive(int servo_no, int data){
float duty = 0.0;
int cnv = 0, angle;
switch(servo_no){
case 5: // Bottom
angle = BOTTOM_SERVO_1_LIST[data]; // Get the angle from the lookup table
break;
case 2: // Neck
angle = NECK_SERVO_2_LIST[data];
break;
case 3: // Ankle
angle = ANKLE_SERVO_3_LIST[data];
break;
case 4: // Claw
angle = CLAW_SERVO_5_LIST[data];
break;
case 6:
angle = KNEE_SERVO_6_LIST[data]; // Knee
break;
}
duty = (5.*angle / 180 ) + 5 ; // Normalize angle to duty cycle
cnv = Cnv_calculator(duty, servo_mod); // Maps duty to CnV
Pwm_servo(servo_no,cnv); // Sends the PWM signal to servos
}void Pwm_servo(int servo_no, int cnv){
TPM0->MOD = servo_mod; // Write the MOD value 1638 to TPM0
if(servo_no==1){TPM0->CONTROLS[0].CnV = cnv;} // Writes the CnV values to the channels
else if(servo_no==2){TPM0->CONTROLS[1].CnV = cnv;}
else if(servo_no==3){TPM0->CONTROLS[2].CnV = cnv;}
else if(servo_no==4){TPM0->CONTROLS[3].CnV = cnv;}
else if(servo_no==5){TPM0->CONTROLS[4].CnV = cnv;}
else if(servo_no==6){TPM0->CONTROLS[5].CnV = cnv;}
TPM0->SC = 0xF; // Start the timer
} int Cnv_calculator(float duty, int mod){
int cnv;
cnv = (duty*(mod))/100.0; // Calculate the CnV given the duty cycle and MOD
return cnv;
}void Motor_init(void){
SIM->SCGC5 |= SIM_SCGC5_PORTB_MASK; // Enable clock to Port B
PORT_PCR_REG(PORTB_BASE_PTR,0) = PORT_PCR_MUX(3); // Configuring PTB-0 Mux (TPM1)
PORT_PCR_REG(PORTB_BASE_PTR,1) = PORT_PCR_MUX(3); // Configuring PTB-1 Mux (TPM1)
PORT_PCR_REG(PORTB_BASE_PTR,2) = PORT_PCR_MUX(3); // Configuring PTB-2 Mux (TPM2)
PORT_PCR_REG(PORTB_BASE_PTR,3) = PORT_PCR_MUX(3); // Configuring PTB-0 Mux (TPM2)
SIM->SCGC6 |= SIM_SCGC6_TPM1_MASK; // Enable clock to TPM1
SIM->SCGC6 |= SIM_SCGC6_TPM2_MASK; // Enable clock to TPM2
SIM->SOPT2 |= 0x01000000; // Clock source selection
TPM1->SC = 0; // Disable Timers
TPM2->SC = 0;
TPM1->CONTROLS[0].CnSC = 0x20 | 0x08; // center-aligned, non inverted
TPM1->CONTROLS[1].CnSC = 0x20 | 0x08;
TPM2->CONTROLS[0].CnSC = 0x20 | 0x08;
TPM2->CONTROLS[1].CnSC = 0x20 | 0x08;
}
Motor drive function send the PWM signal to the motor drivers. There are 8 different directions:
- NW, N, NE, E, W, SW, S, SE
void Motor_drive(int direction, int speed){
int duty;
int cnv,cnv2,cnv3,cnv4;
duty = speed_to_duty(speed); // Maps speed to duty
TPM1->MOD = motor_mod; // Writes MOD value 333 to TPM1 & TPM2
TPM2->MOD = motor_mod;
switch(direction){
case 0: // Go Forward
// Motor Right
cnv = Cnv_calculator(duty*1.15, motor_mod);// Converts duty to the CnV value
TPM1->CONTROLS[0].CnV = cnv; // Writes the CnV value to Channel 0
cnv2 = Cnv_calculator(0, motor_mod);
TPM1->CONTROLS[1].CnV = cnv2; // Writes the CnV value to Channel 1
// Motor Left
cnv3 = Cnv_calculator(duty, motor_mod);
TPM2->CONTROLS[0].CnV = cnv3;
cnv4 = Cnv_calculator(0, motor_mod);
TPM2->CONTROLS[1].CnV = cnv4;
TPM1->SC = 0xF; // Starts TPM1 & TPM2
TPM2->SC = 0xF;
break;
case 2: // Go Left
cnv = Cnv_calculator(duty, motor_mod);
TPM1->CONTROLS[0].CnV = cnv;
cnv2 = Cnv_calculator(0, motor_mod);
TPM1->CONTROLS[1].CnV = cnv2;
cnv3 = Cnv_calculator(0, motor_mod);
TPM2->CONTROLS[0].CnV = cnv3;
cnv4 = Cnv_calculator(duty, motor_mod);
TPM2->CONTROLS[1].CnV = cnv4;
TPM1->SC = 0xF;
TPM2->SC = 0xF;
break;
case 6: //Go Right // Go Right
cnv = Cnv_calculator(0, motor_mod);
TPM1->CONTROLS[0].CnV = cnv;
cnv2 = Cnv_calculator(duty, motor_mod);
TPM1->CONTROLS[1].CnV = cnv2;
cnv3 = Cnv_calculator(duty, motor_mod);
TPM2->CONTROLS[0].CnV = cnv3;
cnv4 = Cnv_calculator(0, motor_mod);
TPM2->CONTROLS[1].CnV = cnv4;
TPM1->SC = 0xF;
TPM2->SC = 0xF;
break;
case 4: // Go Backwards
cnv = Cnv_calculator(0, motor_mod);
TPM1->CONTROLS[0].CnV = cnv;
cnv2 = Cnv_calculator(duty, motor_mod);
TPM1->CONTROLS[1].CnV = cnv2;
cnv3 = Cnv_calculator(0, motor_mod);
TPM2->CONTROLS[0].CnV = cnv3;
cnv4 = Cnv_calculator(duty, motor_mod);
TPM2->CONTROLS[1].CnV = cnv4;
TPM1->SC = 0xF;
TPM2->SC = 0xF;
break;
case 7: // Go NorthWest
cnv = Cnv_calculator(0, motor_mod);
TPM1->CONTROLS[0].CnV = cnv;
cnv2 = Cnv_calculator(0, motor_mod);
TPM1->CONTROLS[1].CnV = cnv2;
cnv3 = Cnv_calculator(duty, motor_mod);
TPM2->CONTROLS[0].CnV = cnv3;
cnv4 = Cnv_calculator(0, motor_mod);
TPM2->CONTROLS[1].CnV = cnv4;
TPM1->SC = 0xF;
TPM2->SC = 0xF;
break;
case 1: // Go NorthEast
cnv = Cnv_calculator(duty, motor_mod);
TPM1->CONTROLS[0].CnV = cnv;
cnv2 = Cnv_calculator(0, motor_mod);
TPM1->CONTROLS[1].CnV = cnv2;
cnv3 = Cnv_calculator(0, motor_mod);
TPM2->CONTROLS[0].CnV = cnv3;
cnv4 = Cnv_calculator(0, motor_mod);
TPM2->CONTROLS[1].CnV = cnv4;
TPM1->SC = 0xF;
TPM2->SC = 0xF;
break;
case 5: // Go SouthWest
cnv = Cnv_calculator(0, motor_mod);
TPM1->CONTROLS[0].CnV = cnv;
cnv2 = Cnv_calculator(0, motor_mod);
TPM1->CONTROLS[1].CnV = cnv2;
cnv3 = Cnv_calculator(0, motor_mod);
TPM2->CONTROLS[0].CnV = cnv3;
cnv4 = Cnv_calculator(duty, motor_mod);
TPM2->CONTROLS[1].CnV = cnv4;
TPM1->SC = 0xF;
TPM2->SC = 0xF;
break;
case 3: // Go SouthEast
cnv = Cnv_calculator(0, motor_mod);
TPM1->CONTROLS[0].CnV = cnv;
cnv2 = Cnv_calculator(duty, motor_mod);
TPM1->CONTROLS[1].CnV = cnv2;
cnv3 = Cnv_calculator(0, motor_mod);
TPM2->CONTROLS[0].CnV = cnv3;
cnv4 = Cnv_calculator(0, motor_mod);
TPM2->CONTROLS[1].CnV = cnv4;
TPM1->SC = 0xF;
TPM2->SC = 0xF;
break;
case 10: // STOP
cnv = Cnv_calculator(0, motor_mod);
TPM1->CONTROLS[0].CnV = cnv;
cnv2 = Cnv_calculator(0, motor_mod);
TPM1->CONTROLS[1].CnV = cnv2;
cnv3 = Cnv_calculator(0, motor_mod);
TPM2->CONTROLS[0].CnV = cnv3;
cnv4 = Cnv_calculator(0, motor_mod);
TPM2->CONTROLS[1].CnV = cnv4;
TPM1->SC = 0xF;
TPM2->SC = 0xF;
break;
default: // STOP
//Motor Left
cnv = Cnv_calculator(0, motor_mod);
TPM1->CONTROLS[0].CnV = cnv;
cnv2 = Cnv_calculator(0, motor_mod);
TPM1->CONTROLS[1].CnV = cnv2;
//Motor Right
cnv3 = Cnv_calculator(0, motor_mod);
TPM2->CONTROLS[0].CnV = cnv3;
cnv4 = Cnv_calculator(0, motor_mod);
TPM2->CONTROLS[1].CnV = cnv4;
TPM1->SC = 0xF;
TPM2->SC = 0xF;
}
}int Speed_to_duty(int speed){
if(speed == 1){return 50;} // Half of the speed
else if(speed == 2){return 75;} // 3/4 of the speed
else if(speed == 3){return 100;} // Full speed
else{return 0;} // Stop
}The purpose of the watchdog is to reset the system if a software error or any error that halts the system occurs. In a decided interval the watchdog has to be serviced. Otherwise the watchdog will reset the system. Watchdog can be used when the hardware is open for errors and the hardware is fragile.
void WDT_init(void){
SIM->COPC = SIM_COPC_COPT(3) &~ SIM_COPC_COPW_MASK &~ SIM_COPC_COPCLKS_MASK ; // Watchdog configuration
}void Service_COP_WDT(void){
SIM->SRVCOP = 0x55;
SIM->SRVCOP = 0xaa;
}Other than using the TPM's Systick timer can be used to create delay.
void Systick_init(void){
SysTick->LOAD = (DEFAULT_SYSTEM_CLOCK/16);
SysTick->VAL=0;
SysTick->CTRL &= ~SysTick_CTRL_CLKSOURCE_Msk;
SysTick->CTRL |= SysTick_CTRL_ENABLE_Msk;
while(1){
if((SysTick->CTRL & SysTick_CTRL_COUNTFLAG_Msk)){
return;
}
}The UART can also check the flags in a polling fashion.
int UART_Rx(void){
while(!(UART0->S1 & UART0_S1_RDRF_MASK)); // Check if the recieve flag is HIGH
return UART0 -> D; // return the UART data
}void UART_Tx(int c){
while((UART0->S1 & UART0_S1_TDRE_MASK) != UART0_S1_TDRE_MASK); // Check if the transmit flag is HIGH
UART0->D = c; // Transmit the data over the UART
}The other crucial element of this project is the wifi capability📌. The onboard wifi module on the ESP 32 is used to communicate with the mobile app📌. The web server is created by the ESP32 and mobile app sends the request to that server📌. The written code is modified version of the available example on the Arduino software, ESP32 -> Camera -> Camera Web Server📌. In order to program the board, the necessary libraries has to downloaded📌. The selected board is the 'ESP32 Wrover Module'📌. The changes on the code are made on CameraWebServer.ino and app_httpd.cpp📌.
The SSID and Password has to be changed. I used the hotspot feature on my phone. Note: You have to change your MAC adress type from 'Randomized MAC' to 'Phone MAC'.
const char* ssid = "Bora's Phone"; // The visible name
const char* password = "********"; // The passwordThe brain of the WebServer is here. I changed the html of the website and included buttons to send request at.
<br>
<section id="buttons">
<div id="controls" class="control-container">
<table>
<tr><td align="center"><button class="button button6" id="get-still">Image</button></td><td align="center"><button id="toggle-stream">Start</button></td><td></td></tr>
<tr><td align="center"><button class="button button2" id="NW" onclick="fetch(document.location.origin+'/control?var=car&val=7');">NW</button></td><td align="center"><button class="button button2" id="N" onclick="fetch(document.location.origin+'/control?var=car&val=0');">N</button></td><td align="center"><button class="button button2" id="NE" onclick="fetch(document.location.origin+'/control?var=car&val=1');">NE</button></td><td></td></tr>
<tr><td align="center"><button class="button button2" id="W" onclick="fetch(document.location.origin+'/control?var=car&val=6');">W</button></td><td align="center"></td><td align="center"><button class="button button2" id="E" onclick="fetch(document.location.origin+'/control?var=car&val=2');">E</button></td></tr>
<tr><td align="center"><button class="button button2" id="SW" onclick="fetch(document.location.origin+'/control?var=car&val=5');">SW</button></td><td align="center"><button class="button button2" id="S" onclick="fetch(document.location.origin+'/control?var=car&val=4');">S</button></td><td align="center"><button class="button button2" id="SE" onclick="fetch(document.location.origin+'/control?var=car&val=3');">SE</button></td><td></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=speed&val=0');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=speed&val=1');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=speed&val=2');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=speed&val=3');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=arm&val=0');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=arm&val=1');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=arm&val=2');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=arm&val=3');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=arm&val=4');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=arm&val=5');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=arm&val=6');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=arm&val=7');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=arm&val=8');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=arm&val=9');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=arm&val=10');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=arm&val=11');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=arm&val=12');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=arm&val=13');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=arm&val=14');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=arm&val=15');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=arm&val=16');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=arm&val=17');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=arm&val=18');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=arm&val=19');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=arm&val=20');">Speed</button></td></tr>
<tr><td align="center"><button class="button button2" id="motor_speed" onclick="fetch(document.location.origin+'/control?var=arm&val=21');">Speed</button></td></tr>
</table>
</div>
</section>
<br>Furthermore, I added the code to encode the recieved request into the 8 bits of the UART.
if (!strcmp(variable, "speed"))
{
serial |= (7 << 5); //type
serial |= (val << 2); //data
Serial.write(serial);
serial = 0;
val = 0;
}
if (!strcmp(variable, "car")) {
if((val<=8)&(val>=0)){
serial |= (1 << 5);
serial |= (val << 2);
Serial.write(serial);
serial = 0;
val = 0;
}
}
if(!strcmp(variable, "arm")){
if ((val >= 0) & (val <= 1)) {
serial |= (2 << 5); //type
serial |= (val << 2); //data
Serial.write(serial);
serial = 0;
val = 0;
}
else if ((val >= 2) & (val <= 6)) {
val -= 2;
serial |= (3 << 5); //type
serial |= (val << 2); //data
Serial.write(serial);
serial = 0;
val = 0;
}
else if ((val >= 7) & (val <= 11)) {
val -= 7;
serial |= (4 << 5); //type
serial |= (val << 2); //data
Serial.write(serial);
serial = 0;
val = 0;
}
else if ((val >= 12) & (val <= 16)) {
val -= 12;
serial |= (5 << 5); //type
serial |= (val << 2); //data
Serial.write(serial);
serial = 0;
val = 0;
}
else if ((val >= 17) & (val <= 21)) {
val -= 17;
serial |= (6 << 5); //type
serial |= (val << 2); //data
Serial.write(serial);
serial = 0;
val = 0;
}
}The app is created from the MIT App Inventor. It is fully customizable and you can change the project layout and
software easily. One crucial adjustment before you run the app is that you have to change the IP address.
In this project, the Arduino does not have a major role. It is used as a QC3 trigger. If a dummy battery was used there won't be any need for an Arduino. However, I used a smart powerbank which only delivers power if the QC3 handshake is initiated. I used Timo Engelgeer's code on github. You can go to the original repo from here: https://github.com/septillion-git/QC2Control. The circuitry is as follows:
The Arduino sends 3.3V from the data + and data - pins on the USB cable as a handshake. After the handshake the powerbank can give 3 different voltages which depends on the voltage given from the data+ and data - pins. In my case I needed 12V hence 3.3v are given from both data pins.
#include <QC2Control.h>
QC2Control quickCharge(4, 5);
void setup() {
quickCharge.setVoltage(12);
delay(1000);
}
void loop() {
}This project is a hardware project as much as a software project. There are 3 main parts in the hardware:
📍 Power Electronics
📍 Motors
📍 Microcontrollers
On the tank, there are 3 different power banks. Each has a different purpose.
🔋The smallest one, 5000mAh, is for powering the microcontrollers, KL25z and ESP32. The microcontrollers are volatile in terms of power. They need a constant flow of 5V. Even a little fluctuation in the voltage can halt their action. The small powerbank is located on the front panel of the tank
🔋The middle one, 10000mAh, is used to power the servos and motor drivers. The servos draw approximately 1-2A and hence it needed a bigger powerbank than the smaller one with a higher current rating. It is located at the bottom of the tank.
🔋The big one, 20000mAh, is used to power the motors. The battery has to be capable of delivering 2A at 12V, thats why the middle powerbank was insufficent(only 1A at 12V). However, the big powerbank has Quickcharge 3. It is great when you are powering a smart device, but the smart powerbanks can't power dummy circuitry. A handshake protocole is needed to deliever power. From the green and white pins of the USB cable 3.3v needs to be outputed. This handshake is initiated with the Arduino Nano. It is located next to the middle battery.
On the tank, there are 2 different motors: Servo and DC.
⚡ There are 5 servos located at the arm of the tank. 3 MG996r(large) and 2 MG90s(small). They are both powered with 5V. Be aware that the standart SG90 will not going to work. The upgraded version MG90s is chosen because the servos carrying a substantial amount of weight.
⚡ There are 2 12V DC motors moving the tank. The motors are driven by the motor driver BTS7960B. The motor driver and the motors are powered from different power sources.
There are 3 different microcontrollers runing the tasks.
🖥️KL25z Freedom board is the brain of the project. It communicates with the ESP32 and drives the motors accordingly.
🖥️The ESP32 creates the webserver and communicates with the mobile app. It sends the recieved data to the KL25z over UART.
🖥️The Arduino Nano is solely for the powerbank.
✔️ Tank Chasis
✔️ 3d Printed Arm
https://thangs.com/designer/m/3d-model/38899
✔️ KL25z Freedom Board
✔️ ESP32-Cam
✔️ Arduino Nano
✔️ 5000mAh Powerbank
https://urun.n11.com/tasinabilir-sarj-cihazi/ttec-powercard-5000mah-slim-powerbank-P486084248
✔️ 10000mAh Powerbank
✔️ 20000mAh Powerbank
✔️ 2 x Motor Driver BTS7960B
https://www.robotistan.com/bts7960b-20-amper-motor-driver-board
✔️ 3 x MG996r Servo
✔️ 2 x MG90s Servo
✔️ USB Micro and C cables
✔️ Switches
✔️ Breadboard
✔️ M4 Screws
✔️ Zip Ties
✔️ Soldering Iron and other equipments