NAVIGATION in Software

Encoding QR-Code in Software NAVIGATION

NAVIGATION
Quick Response Code Decoder In None
Using Barcode Control SDK for Software Control to generate, create, read, scan barcode image in Software applications.
Paint QR Code ISO/IEC18004 In None
Using Barcode generation for Software Control to generate, create QR image in Software applications.
Reflective Strips on Doorframe
Scanning Denso QR Bar Code In None
Using Barcode reader for Software Control to read, scan read, scan image in Software applications.
QR Code ISO/IEC18004 Maker In C#.NET
Using Barcode encoder for .NET Control to generate, create QR Code 2d barcode image in VS .NET applications.
Scan
Drawing QR Code JIS X 0510 In .NET
Using Barcode maker for ASP.NET Control to generate, create QR image in ASP.NET applications.
QR Generation In Visual Studio .NET
Using Barcode creation for Visual Studio .NET Control to generate, create Denso QR Bar Code image in .NET framework applications.
Laser
Creating QR Code JIS X 0510 In Visual Basic .NET
Using Barcode maker for Visual Studio .NET Control to generate, create Denso QR Bar Code image in .NET applications.
Code 3 Of 9 Creation In None
Using Barcode drawer for Software Control to generate, create Code 39 Full ASCII image in Software applications.
FIGURE 33-16 A scanning laser mounted on your robot can be used to detect the patterns of reflective tape located on or near doorways. Since the speed of the scan is known, electronics on your robot calculate distance (and position, given more strips) from robot to door.
Generating UPC-A Supplement 2 In None
Using Barcode encoder for Software Control to generate, create GTIN - 12 image in Software applications.
Painting EAN13 In None
Using Barcode generator for Software Control to generate, create EAN-13 image in Software applications.
robot be at an angle to the door, the tapes will not be parallel. Their angle, distance, and position can once again be interpolated to provide the robot s position relative to the door.
Creating Bar Code In None
Using Barcode printer for Software Control to generate, create barcode image in Software applications.
Printing Code 128 Code Set A In None
Using Barcode generation for Software Control to generate, create Code 128C image in Software applications.
33.7.4 OTHER TECHNIQUES FOR BEACONS AND LIGHTHOUSES
Drawing 2 Of 5 Industrial In None
Using Barcode generator for Software Control to generate, create C 2 of 5 image in Software applications.
Creating EAN / UCC - 13 In Java
Using Barcode generator for Java Control to generate, create UCC.EAN - 128 image in Java applications.
There are scores of ways to relay position information to a robot. You ve already seen two beacon-type systems: infrared and radio frequency. There are plenty more. There isn t enough space in this book to discuss them all, but the following sections outline some techniques you might want to consider. Many of these systems rely on a line of sight between the beacon or lighthouse and the robot. If the line of sight is broken, the robot may very well get lost. Three-Point Triangulation Traditional three-point triangulation is possible using either of two methods:
European Article Number 13 Recognizer In Java
Using Barcode recognizer for Java Control to read, scan read, scan image in Java applications.
EAN13 Encoder In Java
Using Barcode encoder for Java Control to generate, create EAN / UCC - 13 image in Java applications.
Active beacon. A sensor array on the robot determines its location by integrating the relative brightness of the light from three active light sources. Active robot. The robot sends out a signal that is received by three sensors located
Barcode Encoder In VB.NET
Using Barcode creator for .NET Control to generate, create bar code image in .NET framework applications.
Code 39 Extended Reader In Visual Basic .NET
Using Barcode scanner for Visual Studio .NET Control to read, scan read, scan image in .NET applications.
33.8 EXPLORING OTHER POSITION-REFERENCING SYSTEMS
Paint Bar Code In Java
Using Barcode creator for Android Control to generate, create bar code image in Android applications.
Bar Code Creator In Visual C#.NET
Using Barcode generation for .NET framework Control to generate, create barcode image in .NET applications.
Beacon C
Robot
Beacon B
Beacon A
FIGURE 33-17 Three active beacons, connected to fire in sequence, provide both infrared and ultrasonic sound signals. Using a burst of infrared light, the robot times how long it takes for the sonar ping to reach it. Repeated three times one for each beacon the robot is able to make an accurate fix within the room.
around the room. The sensors integrate the robot s position, then relay this information back to the robot (via RF or an infrared radio link).
33.7.5 COUPLED SONAR AND IR LIGHT
This technique calculates time of flight using sound, and it offers excellent accuracy. You equip three active beacons with sonar transmitters and high-output infrared light-emitting diodes. You then connect the three beacons electrically so they will fire in sequence. When fired, both the sonar transmitter and IR LEDs emit a short 40 kHz signal. Because light travels much faster than sound, the robot will detect the IR signal first, followed by the sound signal. The difference in time between the reception of the IR and sound signals represents distance. Each beacon provides a circle path that the robot can be in. All three circles will intersect at only one spot in the room, and that will be the location of the robot. See Fig. 33-17 for a demonstration of how this works.
33.8 Exploring Other PositionReferencing Systems
Over the years a number of worthwhile techniques have been developed to help robots know where they are. We ve covered many of the most common techniques here. If your
NAVIGATION
budget and construction skills allow for it, however, you might want to consider any or all of the following.
33.8.1 GLOBAL POSITIONING SATELLITE
Hovering over the earth are some two dozen satellites that provide accurate worldpositioning data to vehicles, ships, and aircraft. The satellite network, referred to as global positioning system (GPS), works by triangulation: the signals from three or more satellites are received and their timings are compared. The difference in the timings indicates the relative distances between the satellites and the receiver. This provides a fix by which the receiver can determine not only the latitude and longitude most anywhere on the earth, but also elevation. GPS was primarily developed by the United States government for various defense systems, but it is also regularly used by private commerce and even consumers. Until recently, the signals received by a consumer-level GPS receiver have been intentionally fuzzied to decrease the accuracy of the device. (This is called selective availability, imposed by the U.S. government for national security reasons.) Instead of the accuracies of a few feet or less that are possible with military-grade GPS receivers, consumer GPS receivers have had a nominal resolution of 100 m, or about 325 ft. In practical use, with selective availability activated in the GPS satellites, the actual error is typically 50 to 100 ft. Selective availability has since been deactivated (but could be re-activated in the event of a national emergency), and the resolution of consumer GPS receivers can be under 20 to 25 ft. Furthermore, a system called differential GPS, in which the satellite signals are correlated with a second known reference, demonstrably increases the resolution of GPS signals to less than 5 in. When used outdoors (the signal from the satellites is too weak for indoor use), this can provide your robot with highly accurate positioning information, especially if your bot wanders hundreds of feet from its base station. Real-time differential GPS systems are still fairly costly, but their outputs can read into the robot s computer in real time. It takes from one to three minutes for the GPS system to lock onto the satellites overhead, however. Every time the lock is broken the satellite signals are blocked or otherwise lost it takes another one to three minutes to reestablish a fix. If you re interested in experimenting with GPS, look for a receiver that has a NMEA0183 or RS-232 compatible computer interface. A number of amateur radio sites on the Internet discuss how to use software to interpret the signals from a GPS receiver.
Copyright © OnBarcode.com . All rights reserved.