Introduction

Infrared sensors are a form of distance sensors. They tend to be more susceptible to inaccuracies. This is because they send out infrared light and wait for the light to tell distance. Certain colors, especially black, absorb some of the infrared light and may return a false reading.

This was tested on a variety of objects that were what would be considered black. A reading was obtained from almost all of the tested objects, although the distance returned varied. There was one black object that the sensor could not detect at all. The moral of this story is do not rely solely on infrared sensors for distance detection. Redundancy is key when working on robots.

For the GP2Y0D810 sensor, Pololu makes a breakout board that has three pins on it: VIN, GND, and OUT.

Introduction

The HC-SR04 distance sensor is an ultrasonic sensor that is used for distance measurements.

Ultrasonic sensors work by sending out a sound wave and waiting until that wave bounces back to the sensor. This means that the sensor's accuracy can actually change with the speed of sound. However, this is usually not an issue.

This is a cheaper alternative to the Ping sensor. Instead of three pins, it has four: +5V, GND, Trigger, and Echo. This means that one less pin is available on the Arduino, but, depending on the project, that may not matter.

Introduction

Parallax's Ping))) sensor is an ultrasonic sensor that is used for distance measurements.

Ultrasonic sensors work by sending out a sound wave and waiting until that wave bounces back to the sensor. This means that the sensor's accuracy can actually change with the speed of sound. However, this is usually not an issue.

The advantage of the Ping sensor over similar ultrasonic sensors is that it only has three pins: +5V, GND, Trigger. This means that one less pin is used on the Arduino, which may be crucial to a project.

Introduction

XBees are a very simple way to enable wireless communication. Using wireless communication will expand the possibilities of a project, and is practically a necessity for a robot.

Two types of XBee communication that will be discussed are Arduino-Arduino communication and Arduino-Computer communication.

XBees cannot both send and receive data at the same time. If caution it taken, data should not be lost due to this fact.

Introduction

XBees are one form of wireless communication. They use radio frequency to communicate over long distances (from 100m to over 1500m.) They do have issues transmitting through walls and through obstacles, but that is common to many types of wireless communication.

There are two main types of XBees: Series 1 and Series 2 . Series 1 XBees do not say that they are Series 1 on them, but that is one way to determine that they are Series 1. Series 1 is generally easier to use and configure. It is also faster than Series 2. The advantage of the Series 2 XBees is that there is a lower current draw.

This tutorial will go through the configuration of Series 1 XBees.

Introduction

It is possible to chain Arduinos together in such a way as to get communication between the two. Having Arduino-Arduino communication can be useful for many projects, such as having one Arduino to run motors and having another sense the surroundings and then relay commands to the other Arduino. This can be done in several methods, using I2C and Serial, to list a few.

This tutorial will focus on Arduino-Arduino communication through the serial ports (RX and TX).

Introduction

It is one thing to make a GUI and another to make a GUI that people will want to use. Despite the fact that the appearance of a GUI does not really affect how the program runs, it is always prudent to set up GUIs in a way that they could be presented professionally.

Although, this is really only important if the GUI runs properly. Making it function accordingly is always more important than its appearance.

Note: This will focus on improving the GUI example from the previous tutorial.

Analogy

Storing data on a computer is a lot like storing things in a warehouse. If you keep track of where you put things well enough, it shouldn't matter how much stuff you have stored.

Imagine an empty warehouse. If you store something in it, it doesn't really matter if you keep track of it because it's easy to look for it again. If the warehouse were full, you better keep track of where you put your stuff or you'll have to look everywhere for it. In a warehouse, you would probably write down an isle number, a shelf number, and maybe a pallet number. This way, you don't look through all the things, just go directly to the right place.

Introduction

It is often necessary to being to communicate with a robot while it is in use. This can be done simply through a remote control or more complexly through a GUI. The GUI can allow the robot to both send an receive information while a remote control will only be able to send to the robot. A simple way to make a GUI is through Python Tkinter. Using Tkinter along with Serial, the code will allow easy communication between the robot.

This tutorial will show how to use various parts of Tkinter and show how to make a GUI look good.

Introduction

• Use of the faster hardware of the host computer for calculations
• Synchronization of multiple Arduinos
• Use of other information provided by the host computer, like internet connections or larger data files
• Creation of a graphical interface using the host's display or web server