1. ELECTRICAL

2. Circuits Outline • Power Hub • Microcontroller • Sensor Inputs • Motor Driver

3. Power Hub • Purpose: • Regulate input voltage into the circuit • Allows for flexible power supplies that can be used for your robot (input 7V – 36V; output 5V) • Most ICs and electronic components use 5V • Comprised of a voltage regulator and filtering capacitors • Capacitors act like a buffer before current flows to the load • Voltage regulator reduces the range of voltages down to a set value

4. Circuit Diagram Input Voltage Range : 7V – 36V Output Voltage: 5V Input Output

6. Microcontroller • A small computer on an IC that contains a processor core, memory, I/O peripherals • Purpose • The brain of the robot!!! • Programmable – conveniently control behaviour of the robot • We will be using the ATMega 328-PU microcontroller

7. Atmega 328 Pin Assignments

8. Microcontroller Configuration • Requires: • Vcc and GND connections • Analog Reference (set to Vcc) • Value used as the top of the analog input range • Internal Clock (16Mhz Crystal) • Used as clock input to microcontroller • ATMega328-p contains 13 digital and 6 analog pins to be used as I/O peripherals

9. Microcontroller Configuration

10. Sensor Inputs Analog Signals Digital Signals Not continuous Uses specific values to represent information • Continuous • Subject to electrical noise

11. Integration of Microcontroller and Sensors • ATMega328P-PU Pins 23-28 can be used as Analog Input readings from your sensors • Possible Sensors to be used: • Proximity Sensors • Detect presence of nearby objects • Line Sensors • Distinguish between white surfaces and black surfaces • Used to detect bounds for SUMO Arena

12. Motor Driver • Purpose: • Governs the performance of an electronic motor • H-bridge circuits are used to control motors • Enables a voltage to be applied in either direction across a load (controls rotational direction)

13. Motor Driver • We will be using L293D Motor Driver IC • Cheap and easy to use • Works well with the Microcontroller • No need to build an H-Bridge circuit

14. L293D Pin Assignments

15. Motor Driver Configuration • Requires • GND and VCC connections • Enable pin connections from the Microcontroller • Input pin connections from the Microcontroller • Output pins connected to motors • Vs – voltage signal to power the motors

16. Motor Driver Configuration

17. Integration of Microcontroller and Motor Driver ATMega328-P L293D Motor Driver Enable1 Pin 1 (MOTOR 1) Input 1 Pin 2 (MOTOR 1) Input 2 Pin 7 (MOTOR 1) Input 4 Pin 15 (MOTOR 2) Input 3 Pin 10 (MOTOR 2) Enable2 Pin 9 (MOTOR 2) • Digital I/O Pin 12 -> • Digital I/O Pin 13 -> • Digital I/O Pin 14 -> • Digital I/O Pin 19 -> • Digital I/O Pin 18 -> • Digital I/O Pin 17 ->

18. Functionality • In order to turn the right motor, • an enable signal must be given to PIN 9 from the microcontroller • Pins 10 and 15 must set to either HIGH and LOW or LOW and HIGH • Pin 16 must be connected to a 5V power source

19. Functionality • In order to turn the left motor, • an enable signal must be given to PIN 1 from the microcontroller • Pins 2 and 7 must set to either HIGH and LOW or LOW and HIGH • Pin 8 must be connected to a 5V power source

20. End Breadboard Configuration

21. QUESTIONS?