Page1 GRID FOLLOWER v2.0 Keywords Robotics, Autonomous, Line Following, Grid Following, Maze Solving, pre-gravitas Workshop Ready Introduction After an overwhelming response in the event Grid Follower in previous gravitas, robovitics brings to you its successor with maze solving, Grid Follower v2.0 which can be considered as its big brother! Its war time! The enemies are slowly getting on you! Being a part of the Intelligence Division, you are supposed to deploy an autonomous robot which can traverse behind enemy lines and gather sufficient information for you. Beware! There are several enemy checkposts scattered all over their territory without your knowledge. Your robot has to avoid these checkposts and take an alternative path to reach the destination, gather information, and move to some other destination, and so on. And finally, it must return safely to your own territory with valuable information. War has begun! Clock s ticking! Get your grey cells engine vrooming and get set GO! Problem Statement Design and construct an autonomous robot which is capable of traversing the maze by principles of line following and completing the given task. The Task: Reach a sequence of destined coordinates within the grid by avoiding the nodes and taking the bridges and then returning to the starting position. Specifications 1. The robot should fit in a box of dimension 200mm x 200mm x 200mm at every given point time. 2. The weight of the robot should not exceed 5 kg. 3. Ready-made parts should not be used. However, ready-made microcontroller development boards can be used. 4. The voltage should not exceed 12V between any two points in the circuit. 5. The robot must have an on board power source. No external power source will be provided. 6. The robot must be fully autonomous with all powering and motoring mechanisms self-contained. 7. The autonomous robots should have only one power switch which can be used to power on/off the robot. 8. Human operators are not permitted to enter any information into the robot during the event. The robot must not communicate with any wireless device also.
Page2 General Rules 1. Any team that is not ready at the time specified will be removed from the competition automatically. 2. The machines would be checked for their safety before the run and would be discarded if found unsafe for other participants and spectators. 3. Participants should not dismantle their robots before the completion of the whole competition as the machines might need to be verified by the judges at a later stage to ensure that the participants have not violated any of the rules. 4. Judges' decision shall be treated as final and binding on all. Arena 1. The competition platform has been designed with white lines on a black surface. 2. The arena is in the form of a maze which consists of a 5 x 5 squares grid with white lines representing the path on a black surface. The lines will be equally spaced. Each cell of the grid will be a square with inner dimensions 270 mm x 270 mm. The thickness of each white line is 30 mm. 3. There are nodes and bridges on the arena. a. Nodes will be present at the intersection of 2 white lines. The node will be of the size of 30 mm x 30 mm and will be black in colour. Please note that the nodes will NOT be present at all the intersection points. b. The bridge will be joining the centers of 2 adjacent sides of a square. The bridge will be of thickness 30 mm and will be white in colour. 4. There will be no nodes on the Check Line. 5. At the start of each run, the machine must be placed at the start zone within a horizontal square of 240 mm x 240 mm (Starting Point). 6. The dimensions of the arena would be accurate to within 5% or 20 mm, whichever is less. Assembly joints on the arena floor will not involve steps greater than 0.5 mm. 7. Light conditions at the venue might not be uniform. The entire arena will be set up outdoors in ambient lighting conditions. No complaints regarding the lighting conditions will be entertained. 8. NOTE - The orientation of nodes and bridges may not be the same on the day of competition as shown in the figures below. Actual arena will be revealed on the spot.
Page3 Fig.1: Sample Arena Top View Fig.2: Close up view of Node and Bridge
Page4 Fig.3: Sample Arena 3D View Allotted Path Round 1 Single Coordinate Round 1. Each team will be provided a random coordinate on the arena. The coordinate can be anything in between (0,1) and (5,5), except the nodes, thus making 36 distinct coordinates. Please refer the arena diagram given below for clarity. 2. No coordinates will be assigned on the Check Line. For details, refer the game play rules mentioned later. 3. Nodes will NOT be assigned as the target coordinate(s). Nodes should be the coordinates which the robot must avoid. 4. Now, the robot has to start from the starting point, go to the allotted coordinate, stop there for some time (minimum 5 seconds), and then find a way back to the starting point. 5. The robot must avoid the nodes and take the bridges in order to traverse the maze. 6. For example, if a team is allotted a coordinate of (3,5), then their robot should follow the following allotted path: a. Start at the starting point and reach (0,0). b. Then go from (0,0) to (3,5) by following any path, avoiding nodes and taking bridges, but the c. Stop at (3,5) for some time, minimum 5 seconds.
Page5 d. Then find a way back to (0,0) by following any path, avoiding nodes and taking bridges, but the e. And finally, reach the starting point from (0,0). Round 2 Double Coordinate Round Fig.4: Location of coordinates on the arena 1. For this round, two coordinates will be given to each selected team randomly. 2. The coordinates can be anything in between (0,1) and (5,5), except the nodes, thus making 36 distinct coordinates. Please refer the arena diagram given above for clarity. 3. No coordinates will be assigned on the Check Line. For details, refer the game play rules mentioned later. 4. Nodes will NOT be assigned as the target coordinate(s). Nodes should be the coordinates which the robot must avoid. 5. Now, the robot has to start from the starting point, go to the first coordinate, stop there for some time, then go to the second coordinate, and then find a way back to the starting point. 6. The same arena will be used for both the rounds. 7. For example, if a team is allotted the coordinates of (2,3) and (4,1), then their robot should follow the following allotted path: a. Start at the starting point and reach (0,0). b. Then go from (0,0) to (2,3) by following any path, avoiding nodes and taking bridges, but the
Page6 c. Stop at (2,3) for some time, minimum 5 seconds. d. Then go from (2,3) to (4,1) by following any path, avoiding nodes and taking bridges, but the e. Stop at (4,1) for some time, minimum 5 seconds. f. Then go from (4,1) to (0,0) by following any path, avoiding nodes and taking bridges, but the g. And finally, reach the starting point from (0,0). Rules of Game Play Pre-Game Rules Allotment of Coordinates 1. Coordinates will be allotted 24 hours before the actual game play. This means that the coordinates of the first round will be given to the teams a day before the actual event. After the completion of the first round, the selected teams will be given the coordinates for the second round, which will be held the next day. 2. For Round-1, one coordinate will be allotted, whereas for Round-2, two coordinates will be allotted. 3. Each team will be given one/two (depending upon the round) random coordinates (on the arena) a day before the round. The procedure of giving coordinates will be totally random. Complaints from the participants regarding this procedure will NOT be entertained. 4. After the teams get their coordinates, if required, they will have to re-design or modify their code as per the allotted path. The details of the allotted path are given above. 5. The allotted coordinate(s) will NOT be changed under any circumstances. The team has to accept the given coordinate or stand disqualified. 6. The robots are supposed to traverse the arena from the start point and back to the start point in the lowest time possible. The time for which the robot waits at the allotted coordinate(s) will not be calculated. 7. Sufficient calibration time will be given to the participants before their run. Round 1 Single Coordinate Round 1. In this round, only one coordinate is allotted. This means that the robot has to start from the starting point, go to the given coordinate, stop for some time (minimum 5 seconds), and then resume its journey back to the starting point. 2. There will not be any coordinates assigned on the Check Line. 3. The robot must stop at the coordinate for at least 5 seconds or else it won t be counted. 4. The timer starts as soon as the robot crosses the start region and stops when it reaches the start region. The timer will also stop momentarily when the robot waits at the allotted coordinate. 5. The robots can follow any track on the grid to follow the allotted path, but the path must not deviate from the grid. In other words, only the tracks specified on the grid should be followed. 6. The robot must avoid the nodes. If the robot crosses a node without detecting it, it will invite penalty. However, if the robot detects the node correctly and retraces its path, it will not be considered as a penalty. However, no preference will be given if the robot takes a bridge to avoid the node. 7. A maximum of 5 minutes will be given to each team for their robot to complete the run. 8. The rules of penalties and disqualifications will be strictly followed.
Page7 9. The overall time will be equal to the original amount of time taken plus the extra time added due to penalties and restarts. 10. After the completion of this round, top 16 teams will be selected to proceed to the next round. These teams will be allotted two coordinates for the next round immediately. Round 2 Double Coordinate Round 1. In this round, two coordinates are allotted. This means that the robot has to start from the starting point, go to the first coordinate, stop for some time (minimum 5 seconds), then go to the second coordinate, stop there for some time (minimum 5 seconds), and then resume its journey towards the starting point. 2. There will not be any coordinates assigned on the Check Line. 3. The robot must stop at the coordinates for at least 5 seconds or else it won t be counted. 4. The timer starts as soon as the robot crosses the start region and stops when it reaches the start region. The timer will also stop momentarily when the robot waits at the allotted coordinate. 5. The robots can follow any track on the grid to follow the allotted path, but the path must not deviate from the grid. In other words, only the tracks specified on the grid should be followed. 6. The robot must avoid the nodes. If the robot crosses a node without detecting it, it will invite penalty. However, if the robot detects the node correctly and retraces its path, it will not be considered as a penalty. However, no preference will be given if the robot takes a bridge to avoid the node. 7. A maximum of 7 minutes will be given to each team for their robot to complete the run. 8. The rules of penalties and disqualifications will be strictly followed. 9. The overall time will be equal to the original amount of time taken plus the extra time added due to penalties and restarts. Disqualifications and Penalties 1. A robot will be penalised if a. Any member of the team touches it. b. Doesn t detect a node and crosses over it. c. Leaves the path and goes haywire. However, if the robot catches up with its path or some other part of the grid on its own, it won t be considered as a penalty. 2. Any robot not confirming to the specifications provided will be instantly disqualified. 3. Any robot that damages the arena will be disqualified. 4. A member of the team will be allowed to touch the robot only thrice and have a maximum of two restarts. After that, the robot will be disqualified. 5. Any team not present at the allotted time will be disqualified by default. 6. Any team not ready to accept the allotted coordinate will be disqualified. 7. For each penalty, 10 seconds will be added to the final time and for each restart, 20 seconds will be added to the final time.
Page8 Judging Criteria 1. The total time (running time + penalties) will be calculated for each team in both the rounds. After Round-1, based on that, Top 16 teams will be selected for Round-2. The lower the total time, the better it is! 2. In case of a tie, the two teams will be given another chance to prove their calibre in the same arena, with same/different (it depends) allotted coordinates. Team Specification A team can have a maximum of 4 members. Students of different educational institutes can form a team together. Eligibility All students with a valid identity card of their respective educational institutes are eligible to participate. Intercollegiate teams are allowed. Resources http://www.techfest.org/resources/resources_for_competitions/nexus/introduction_to_line_following.pdf http://maxembedded.wordpress.com/ Workshop A workshop free of cost can be provided to the participants and other interested students on autonomous robots, line following and grid solving.