1 Abstract—The IEEE micromouse competition has been apopular event among engineering students and engineers. Amicromouse is an autonomous vehicle whose objective is tofind the center of a 16 by 16 cell maze within 10 minutes.After exploring the maze for some time, the micromouse willattempt to make its fastest run from the starting point to thedestination cells. This report summarizes the design andimplementation of the MightyMouse project for the spring andfall semesters of 2005. The design method of theMightyMouse project consisted of two stages. The first stagewas to design and construct individual components. Thesecond stage of the design process was to interface thecomponents to form the final prototype. The individualcomponents of micromouse system consist of the motorcontrol system, navigation sensor array, digital compass fordetecting orientation, and a mapping system for navigating themaze intelligently. A test plan was developed in order tovalidate the overall performance of the micromouse. A lifeproduct life cycle and reliability reports have also been writtenin hopes to encourage and aid future micromouse teams.Index Terms—micromouse, autonomous, maze, IEEEcompetitionI. INTRODUCTIONHE micromouse is an autonomous vehicle whose goal isto find the center of a maze. The official IEEEMicromouse Competitions began in 1987 at the WorldMicromouse Competition, where David Otten of MITcaptured first and second place with his MITEE Mouse. Thiscompetition used a new scoring system design to rewardintelligence, efficiency, and self reliance. Micromousecompetitions have become a popular event among engineeringstudents and engineers.II. PROJECT DESCRIPTIONA. Problem StatementDesign and construction of a micromouse requires a broadrange of engineering skills. This combined with an opendesign process makes the micromouse project a very practicalManuscript received December 12, 2005. This senior design project wassponsored by Dr. Herb Hess of the Electrical Engineering Department,University of Idaho.and challenging senior design project.1) Objectives: The primary objective of this project is tobuild an autonomous vehicle, a micromouse, according toIEEE specifications which is able to navigate to the center of amaze. A secondary objective is to design a full size maze alsoin accordance to IEEE specifications.2) Constraints: Constraints for the micromouse come fromregulatory competition rules. The mouse size, time allowedto solve the maze, methods for solving the maze, and amonetary limit placed on the final prototype are all constraintsimposed by IEEE competition rules.a) Size: The mouse is can be no larger than 25cmsquare.b) Time Limit to solve maze: During a IEEEcompetition the micromouse has 10 minutes to solvethe maze and complete the run.c) Battery life: The batteries must supply power to themicromouse for at least 10 minutes.d) Micromouse expenses: The total cost for Micromousemust not exceed $500.e) Maze: The maze consists of 16 x 16 cells; each cell is18 cm square. The southwest corner is the startingcell. The four center cells are the destination.B. Solution Method1) Brief Description: There are two fundamental phases toour design process. The first phase was to design individualcomponents of the micromouse and get them to operateaccording to individual specifications independent of oneanother. The second phase was to interface the individualcomponents and have the micromouse operate as oneautonomous unit. The first semester of the Senior Designcourse was dedicated to working on the individualcomponents. The goal of the second semester was to integratethe individual components. The individual workingcomponents include the navigation sensor array, mappingalgorithm, distance and bearing devices, motor control, andchassis designAn effective micromouse design must perform thefollowing functions in order to find the center of a mazea) Recognize walls and openingsb) Stay centered within each cellc) Know position and bearing within the mazed) Control the distance needed to travele) Make precise 45˚ and 90˚ turnsMightyMouse: An Autonomous Maze SolvingRobotKelly Ridge, Sanjeev Giri, Peter Shaw, Jason FlynnT2f) Perform mechanicallyg) Navigate the maze intelligently2) Overview of Micromouse functions: The mouse mustrecognize walls and openings in order to navigate the mazeand prevent crashes. The navigation sensor array provides themouse with this information. The navigation sensor arrayconsists of a combination of four short-range and two long-range infrared sensors.The mouse must stay centered within the maze to preventcompounding errors in distance and position calculations. Adigital compass determines if the deviates from its desiredbearing. This information is sent to the motor control systemto make proper corrections, either speeding up or slowingdown one wheel.The motor control portion of the project is responsible forsafely moving the micromouse through the maze. There aretwo maximum speeds, one for the mapping portion of thecompetition and one for the racing portion of the competition.The motor control code is given a distance to travel as input.It is then the responsibility of the motor control to accelerateand decelerate the mouse during travel. The rate ofacceleration is fixed based upon the traction of the wheels onthe maze surface.In order to ensure that the mouse is not slipping, the motorsare controlled with PI feedback. The shaft encoders (built intothe motors) read in the speed of the wheels and send this datato the motor control code that adjusts the speed of each wheelaccordingly.The mouse must keep track of position and bearing duringeach run to provide navigation information to the mappingsystem. The shaft encoders that are built in to the motorsmonitor the distance the micromouse travels. The electroniccompass determines which direction the micromouse is facing.The combination of these two systems provides the dataneeded by the mapping and navigation systems.To move efficiently through the maze the micromouse mustbe able to make precise 90° turns. The digital compass ispolled during turns to provide control feedback to the motorsand navigation systems.The mechanical soundness of the micromouse design is animportant factor. The chassis needs to keep the systems stableduring operation so accurate data is recorded. The chassisalso keeps the drive train in line in order to reduce the numberof path corrections made.To