Circuits Outline Power Hub Microcontroller Sensor Inputs Motor
Driver
Slide 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
Slide 4
Circuit Diagram Input Voltage Range : 7V 36VOutput Voltage: 5V
Input Output
Slide 5
Slide 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
Slide 7
Atmega 328 Pin Assignments
Slide 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
Slide 9
Microcontroller Configuration
Slide 10
Sensor Inputs Analog Signals Continuous Subject to electrical
noise Digital Signals Not continuous Uses specific values to
represent information
Slide 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
Slide 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)
Slide 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
Slide 14
L293D Pin Assignments
Slide 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
Slide 16
Motor Driver Configuration
Slide 17
Integration of Microcontroller and Motor Driver ATMega328-P
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 -> 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)
Slide 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
Slide 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