This is the Revision B verion of the Laser1 Module.

Laser1 Module (Revision B)

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1. Introduction
2. Programming
3. Hardware
- 3.1 Circuit Schematic
- 3.2 Printed Circuit Board
4. Software
5. Issues
6. References

1. Introduction

The Laser1 module provides the basis for a laser bearing finder. This module must be placed on a platform that can swivel in place. This module can detect reflected back laser beam energy at supstantial distances (10+ meters.) Reflective tape makes an excellent laser reflector. Please check the references section for more information. In particular, [Ubersitzig1999] is the root seriels of articles that motivates the desire for this sensor.

2. Programming

There is no programming yet.

3. Hardware

The hardware consists of a circuit schematic and a printed circuit board.

3.1 Circuit Schematic

The schematic for the Laser1 Module is shown below:

The parts list kept in a separate file -- laser1.ptl.

3.2 Printed Circuit Board

The printed circuit board files are listed below:

laser1_back.png: The solder side layer.
laser1_front.png: The component side layer.
laser1_artwork.png: The artwork layer.
laser1.gbl: The RS-274X "Gerber" back (solder side) layer.
laser1.gtl: The RS-274X "Gerber" top (component side) layer.
laser1.gal: The RS-274X "Gerber" artwork layer.
laser1.drl: The "Excellon" NC drill file.
laser1.tol: The "Excellon" tool rack file.

4. Software

There is no software yet.

5. Issues

Any fabrication issues are listed here.

The hole for the laser beam is too small.
The alignment holes are too small for any reasonable hardware.
The alignment holes are too close, move further out.

6. References

[AcronameServo]: Modifying Servos for Continuous Rotation. Published online by Acroname at URL: http://www.acroname.com/robotics/info/ideas/continuous/continuous.html.
[Bertke1994]: Mobile Robot Localization Using Landmarks by Margrit Bertke and Leonid Gurvits in the proceedings of the 1994 International Conference on Intelligent Robots and Systems (IROS '94), pages 135-142. URL: http://www.umiacs.umd.edu/~betke/#landmarkpaper
[Borenstein1996]: "Where am I?" -- Systems and Methods for Mobile Robot Positioning by J. Borenstein, H. R. Everett, and L. Feng published by A. K. Peters, Ltd. ISBN: 156881058X. An on-line version of the paper is available at URL: http://www.eecs.umich.edu/~johannb/pos96rep.pdf. Note: There is a slightly different 1995 edition entitled Navigating Mobile Robots: Systems and Techniques that is out of print ASIN: 1568810660 .
[Buse2000]: Variable Speed Control Modification to the Futaba S3003 RC Servo by Lee Buse published in the September 2000 issue of the Seattle Robotics Encoder. URL: http://www.seattlerobotics.org/encoder/200009/S3003C.html.
[McGillem1989]: A Beacon Navigation Method for Autonomous Vehicles by Clare D. McGillem and Theodore S. Rappaport published in IEEE Transactions on Vehicular Technology Vol. 38 No. 3 August 1989, pages 132-139. Note: The algorithm proper can be found in equations (7) through (16). The derivation of the algorithm can be found in the appendix. In additin, I have written a C program that implements the described algorithm.
[Ubersitzig1999]: A Circular Navigation System written by Jim Ubersetzig, published in three parts in the September, October, and November 1999 issues of The Robot Builder newsletter of the Robotics Society of Southern California. URL: http://www.rssc.org/. Note: At the end of the third part of the series, there is mention of a continuation of the article (part 4) in the next month of "The Robot Builder"; to the best of our knowledge this continuation article has not actually been published.
[Vannoy2001]: Accurate Autonomous Robot Laser Navigation Using Only Passive Reflectors by Richard T. Vannoy II published in the September 2001 issue of the Seattle Robotics Encoder. URL: http://www.seattlerobotics.org/encoder/200109/lasernav.htm.