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Rules

If you have any questions about rules or the event, you may post questions on the forum or email them to savage@wpi.edu. All questions will be publicly posted on the forum. All responses will be publicly dispersed on the website under the Updates link http://users.wpi.edu/~savage/Rules/updates.html). Please read the rules and Updates page before asking questions as they may already be answered.

Alternatives for game play for remote competitions with fewer than 12 teams are located at the end of the rules.

Game Hint

NaHCO₃ + CH₃COOH -> CO₂ + H₂O + CH₃COONa

1. Objective

To design and build a radio- and autonomously-controlled robot that will defeat your opponents in competition.

The winner of the competition is defined as the team or coalition that wins all best two-of-three rounds in the elimination bracket.

2. The Game

• 2.1 Definitions:
  • 2.1.1 Coalition: Teams allied together either randomly in qualification rounds or chosen to work together during elimination rounds. Members of a coalition always share a coalition color.
  • 2.1.2 Coalition Colonels: The top-ranked teams at the end of the qualifying matches.
  • 2.1.3 Starting Zones: Two locations at the short ends of the field, designated by the outside edge of the tape, where robots begin the match.
  • 2.1.4 Ballcano!: Central ramp structure which contains the Crater.
  • 2.1.5 Oasis Scoring Implement (OSI): Mobile scoring structures
  • 2.1.6 Ping Pong Ball: A standard 38mm ping pong ball, colored red, blue, or white.
  • 2.1.7 Tubular Bonus Structure (TBS): Two bars at the back corners of the field upon which the OSIs may be hung.
  • 2.1.8 Flags: Indicator devices placed in a visible location on the rear field wall to mark the points scored in autonomous.
  • 2.1.9 Crater: The depression in the center of the Ballcano!.
  • 2.1.10 Ball Eruption Device (BED): A piece of fabric in the Crater used to expel the ping pong balls.
• 2.2 Field Description
  • 2.2.1 The field is 8' x 12'. A wooden frame that is approximately 2.5" high and 0.75" thick forms the field wall (the outer boundaries of the playing area).
  • 2.2.2 The surface of the playing area is "high-traffic" carpet that may have minor bumps and surface irregularities.
  • 2.2.3 Robots will begin the match in one of their coalition's starting zones. Only one coalition robot may start in each starting zone. Teams will be designated as either "Red" or "Blue" on a match-by-match basis as noted on the Match List.
  • 2.2.4 There will be 32 white ping pong balls, 20 red ping pong balls, and 20 blue ping pong balls on the field.
    • 2.2.4.1 The 32 white ping pong balls will begin in the Crater
    • 2.2.4.2 Ten of each color ping pong balls will begin in groups of 5 in marked locations on the field.
    • 2.2.4.3 Each team in a coalition may begin the match with up to 5 of their colored ping pong balls within their robot. Any remaining balls will be placed in the Crater.
  • 2.2.5 There are two Oasis Scoring Implements for each Coalition that will begin in marked locations near the corners of the field.
  • 2.2.6 There is one BED that begins the match in the Crater.
  • 2.2.7 All field dimensions should be considered to be +/- 0.5".
• 2.3 Match Scoring
  • 2.3.1 All scoring will be calculated when all items on the field have come to rest
  • 2.3.2 A ping pong ball is considered scored if it is supported by an OSI, the BED, or by a ball considered scored. A ball may only be scored once during a match.
  • 2.3.3 An OSI is considered Hanging if it is in contact with a TBS and is not in contact with a robot of the corresponding coalition, and is not in contact with the playing surface.
  • 2.3.4 A robot is considered Sacrificed if it is touching the BED within the Crater, or is touching a ball considered scored in the Crater.
  • 2.3.4 Autonomous Scoring
    • 2.3.4.1 For every robot in contact with one of their coalition's OSIs, which is in contact with the playing surface, at the end of autonomous, the corresponding coalition will receive five points represented by a flag placed in a visible location on the rear field wall.
    • 2.3.4.2 For every robot in contact with one of their coalition's OSIs, which is not in contact with the playing surface, at the end of autonomous, the corresponding coalition will receive 12 points represented by a flag placed in a visible location on the rear field wall.
    • 2.3.4.3 For every robot in contact with one of their coalition's OSIs, which is not in contact with the playing surface, at the end of autonomous, while within a starting zone of their coalition's color, the corresponding coalition will receive 20 points represented by a flag placed in a visible location on the rear field wall.
  • 2.3.5 At the end of the match, each coalition will receive points based on the following criteria:
    • 2.3.5.1 Each colored ball scored in the Crater is worth 1 point for its corresponding coalition.
    • 2.3.5.2 Each white or colored ball in a corresponding colored OSI is worth 2 points.
    • 2.3.5.3 Each Hanging OSI is worth 5 points.
    • 2.3.5.4 Each Sacrificed robot is worth 8 points.
    • 2.3.5.5 Each Hanging OSI doubles the value of the scored balls within that OSI.
    • 2.3.5.6 Points are awarded for autonomous scores as indicated by the flags.
  • 2.3.6 The points will be calculated in the following order:
    1. Robots Sacrificed will be counted, then
    2. All Robots will be removed from the Crater by the referees, then
    3. OSIs will be determined to be Hanging, then
    4. Balls will be counted within the OSIs, then
    5. Balls will be counted within the Crater, then
    6. All autonomous flags will be counted and points awarded, then
    7. Penalties will be applied, then
    8. All negative scores will be changed to zero.
  • 2.3.7 A team's point total is defined as the number of points received by their coalition, including any penalties.
  • 2.3.8 The winner of the match is the coalition with the higher point total.
  • 2.3.9 Penalties:
    • 2.3.9.1 A penalty is defined as a deduction of 10 points.
    • 2.3.9.2 Repeated or intentional receiving of penalties will result in a disqualification, per rule 2.7.1.1.
  • 2.3.10 Tiebreakers:
    • 2.3.10.1 Highest score in autonomous.
    • 2.3.10.2 The Coalition with the fewest number of penalties.
    • 2.3.10.3 The Coalition with the most goals Hanging.
    • 2.3.10.4 The Coalition with the most Robots Sacrificed.
    • 2.3.10.5 If a tie still exists, the match will be declared a tie.
• 2.4 Competition Structure
  • 2.4.1 The competition will consist of Qualifying Matches followed by Elimination Matches.
  • 2.4.2 Qualifying Matches
    • 2.4.2.1 All teams will play in the same number of Qualifying Matches. The number of qualifying matches at each event will be determined by the length of the event and the number of teams competing.
      • 2.4.2.1.1 For all teams to have an equal number of official matches, some teams may be required to play an extra match, known as a surrogate match. This match does not count in the official ranking of any surrogate teams participating. Surrogate matches will be indicated on the match list.
    • 2.4.2.2 Teams will be given their schedule of qualification matches no later than the start of the first match of that day's event.
    • 2.4.2.3 Teams will be randomly assigned to coalitions during qualifying matches. The qualification match schedule will show the match number, the four teams competing in each match, and the color they are assigned for that match.
  • 2.4.3 Ranking: At the end of the qualifying matches, teams will be ranked based on the following:
    • Greatest number of wins (a tie is considered half a win), then
    • Highest average point total , then
    • Flip of a coin (or electronic substitute), heads and tails to be determined by the head referee.
  • 2.4.4 Elimination Matches
    • 2.4.4.1 The number of coalitions participating in elimination matches will be no less than four, but may be increased prior to the start of the event based on the number of teams participating.
    • 2.4.4.2 Coalition Drafting
      • 2.4.4.2.1 At the conclusion of the qualifying matches, the top-ranked teams will be designated as Coalition Colonels. In order of their ranking, each Coalition Colonel will draft one team. An additional drafting round may take place at the discretion of the tournament director, increasing the teams per elimination coalition to 3.
      • 2.4.4.2.2 Coalition Colonels may not draft other teams designated as Coalition Colonels or those already drafted into service for other coalitions.
      • 2.4.4.2.3 If a team declines the draft of any Coalition Colonel, they WILL NOT be allowed to play in the elimination matches.
    • 2.4.4.3 During elimination matches, the #1 ranked coalition will play the lowest ranked coalition entering the elimination matches (i.e. if there are eight coalitions, #1 will play #8). The #2 coalition will play the second-to-lowest ranked coalition and so on.
    • 2.4.4.4 Elimination matches will be a best 2-of-3 format.
    • 2.4.4.5 Each coalition partner must play at least once during the first 2 matches of a best 2-of-3 round. If a robot becomes seriously damaged, the Coalition Colonel must inform the head referee immediately after the match in which the damage occurred. The head referee will then decide if the robot is exempt from this rule. The damaged robot must be re-inspected by the head referee before each best 2-of-3 round and must be re-declared inoperable in order to continue receiving the exemption.
    • 2.4.4.6 Ties in elimination matches will be replayed.
• 2.5 Driver Rotation
  • 2.5.1 During each match, teams will be required to switch their drivers halfway through the driver control period as indicated in Section 2.6. There will be a ten-second period during which the drivers must complete the switch or power will be shut off for the duration of the match.
  • 2.5.2 Teams may choose to have another student operating other non-driving functions of the robot during the match. This optional position is not required to switch during a match.
  • 2.5.3 An ordered list of drivers must be submitted by a team member prior to the start of the first match of the competition. Team members must drive according to this list.
  • 2.5.4 Teams must have at least four different students to rotate through the driver position. In the event that fewer than four students attend the competition, teams must still place four students in the ordered list and forfeit the driving time of the missing student(s).
  • 2.5.5 All four student participants of the team must drive the robot within the first two official matches in which the team places a robot on the field. Once the required team members (per 2.5.4) have driven the robot, teams must continue switching drivers during their matches but are not required to continue in the order shown on the list in 2.5.3. If it is known in advance that a student will be late to the event, please contact the tournament director at savage@wpi.edu at least two days prior to the event and we will discuss possible alternatives.
• 2.6 Match Sequence
  • Each match is two minutes and 10 seconds long
  • 0-10 seconds - Robots enabled under Autonomous Control
  • 10 seconds- The BED is lifted by the Head Referee, causing all the ping pong balls in the Crater to cascade down the Ballcano!
  • 10-70 seconds - Robots under first Driver Control
  • 65-75 seconds - Driver switch period
  • 70-130 seconds - Robots under second Driver Control
  • 130 seconds - Match ends, robots disabled
• 2.7 General Rules
  (All referee decisions regarding rules of play and judgments are final)
  • 2.7.1 Definitions
    • 2.7.1.1 Disqualification: Robots may be disqualified based on their actions that violate the rules of the game. If a referee calls for a disqualification during a match, power will be shut off to the offending robot immediately. In all cases, the offending robot will receive a loss and zero points. The remaining members of both coalitions will receive the win/loss and their respective point totals in qualification matches. If a team is disqualified during an elimination match the coalition will receive a loss and the opposing coalition will receive a win.
    • 2.7.1.2 Pinning: A robot is considered pinned when it is being held against a field obstacle or another robot by a robot from an opposing coalition and cannot move in any direction. The closest referee will begin counting the pin from the moment the robot becomes immobilized.
  • 2.7.2 Robots may not intentionally tip an opposing team's robot. The tipping robot will be disqualified from the match if, in the referee's opinion, they initiated a lifting action that results in tipping. In incidents where the tipped robot initiates action or both robots are in motion, the involved robots may be disabled.
  • 2.7.3 Robots may not physically interact with anything outside of the field.
  • 2.7.4 At the start of the match, teams must place their robot such that it is fully contained within one of the starting zones corresponding to their coalition color.
  • 2.7.5 Objects Removed from the Field
    • 2.7.5.1 Any ping pong ball which leaves the playing area during a match will not be returned to the field and is ineligible to be scored.
    • 2.7.5.2 Any OSI which leaves the playing area during a match will be returned to the field approximately where it left the field, minus any ping pong balls it contained.
    • 2.7.5.3 If a robot leaves the playing area during a match, it will be disabled for the remainder of the match and will not be returned to the field.
  • 2.7.6 Robots may not remove or cause any ball to be removed from any opposing coalition's OSI. Any balls removed in this manner, including those that leave the field, will be returned to the OSI from which they were removed at the end of the match before points are calculated. If it is determined that the descoring was intentional, the offending robot will receive a penalty.
  • 2.7.7 Robots may not intentionally tip an opposing coalition's OSI if it is in contact with the playing surface. The tipping robot will be disqualified from the match, if in the referee's opinion, they initiated an action that caused the goal to tip over. In incidents where robots from two different coalitions are engaging the same goal, it is at the referee's discretion whether a robot will be disqualified.
    • 2.7.7.1 Once an OSI has been hung by a robot on its corresponding coalition, robot interaction with that OSI is no longer governed by rule 2.7.7 and rule 2.7.6 for the rest of the match.
  • 2.7.8 Referees will disqualify any robot they deem to be a safety hazard.
  • 2.7.9 Team members may interact with their robot during a match only through the transmissions of the radio-controller. Only designated Drivers or Operators may be in contact with the controls during the match.
    • 2.7.9.1 Only team members who will be using the controls during the match will be allowed at the field. No coaches are allowed during a match, however team members who have already driven or are waiting to drive may advise the drivers at their discretion.
    • 2.7.9.2 All team members who will be driving during the match must stay within their coalition station for the entirety of the match. Repeat violations of this rule may result in disqualification at the discretion of the referees.
    • 2.7.9.3 Teams must place their controls at a designated location before the beginning of the match. Team members may only touch these controls during driver control after the referees have signaled the start of driver control.
  • 2.7.10 Damage to the playing field, the objects, or the control system may result in the disabling or disqualification of the robot at the discretion of the referees. If the referee determines that further movement of the robot would result in field damage, it will be disabled. Removal of OSIs and ping pong balls from the field will be considered field destruction.
  • 2.7.11 Referees may request that teams alter any portion of their robots that are considered safety hazards or damaging to the playing field or scoring objects at any point during the competition. It is the right of the referees to prevent teams from playing in matches until such changes are made to the robot.
  • 2.7.12 Strategies aimed solely at the destruction of or damage to an opponent's robot or the field are not in the spirit of the competition and will not be allowed. This includes intentionally removing game objects from the field. Repeat violations of this rule may result in disqualification at the discretion of the referees.
  • 2.7.13 If a robot is pinned for five seconds, the pinning team must immediately disengage and move at least 12" away from the pinned robot. Failure to do so will result in an immediate penalty, as well as a penalty for each additional five seconds per rule 2.3.9. Robots that accumulate multiple pinning penalties in a match are subject to immediate disqualification from the match.
  • 2.7.14 All parts of the robot must remain attached to the robot for the duration of the match and must not cause any hazard of entanglement to the other robots. Any infraction of this rule may result in an immediate disqualification. Minor pieces that unintentionally become detached from the robot, do not affect the outcome of the match, or are the result of improper design/construction will not cause a disqualification.
  • 2.7.15 Teams are allowed to modify their robots between matches as long as the robot remains compliant with all specifications and rules after the modification. Any significant modification should be brought to the attention of the referees or head inspector prior to the start of the team's next match. Teams may be subject to re-inspection at the discretion of the referees/head inspector. While teams are allowed to modify their robots between matches, multiple robots per team are not allowed.
  • 2.7.16 All questions or requests for rules clarifications should be submitted via the web forum located on the event website. Questions and answers will be publicly posted on the event website.

3. The Robot

• 3.1 Size Restriction
  • 3.1.1 At the start of each match, every part of the robot except for the flag holder (drinking straw, as specified in rule 3.4.4) must fit, unconstrained, in a stable position, within a box 15.25" by 15.25" by 12.25" in any orientation. The robot must be fully self-supported, in contact only with the horizontal, carpeted (or taped) surface of the playing field.
• 3.2 Weight Restriction
  • 3.2.1 Each robot's weight must not exceed 8 lbs.
  • 3.2.2 The 8 lb. limit does not include the robot battery, the radio transmitter (i.e. the controls) or the color-designating flag.
• 3.3 Controls
  • 3.3.1 Teams will each bring and provide their own controls to the competition. Crystals will be provided at the competition at the start of each match.
  • 3.3.2 Radio operation of the robots is not permitted in the pits. Teams should bring their phone cords/tethers for testing and operating in the pits. It is advisable that teams not bring their radio crystals to the competition.
• 3.4 Construction Rules
  • 3.4.1 A robot must be designed to operate by reacting only against features within the confines of the playing field boundaries.
  • 3.4.2 Gaining traction by use of adhesives or by abrading or breaking the surface of the playing field is not allowed and will be considered to be damaging the playing field and subject to disqualification.
  • 3.4.3 Teams must have their assigned team number clearly marked on their robot such that it is visible from 15' away. The numbers should be at least 3" high, 1/4" thickness and be on opposing sides of the robot. Team numbers will be assigned via the Savage Soccer website team list.
  • 3.4.4 Teams must place a standard drinking straw, cut to six inches long on their robot, such that the straw is perpendicular to the ground. The top of the straw must extend above the top of the robot while in its starting configuration. This straw will have a colored flag inserted into the top to designate the coalition color. Prior to each match, teams must place the correct color flag on their robot, as indicated on the match list. Flags will be provided at the start of the match and must be removed from the robot before leaving the playing field. Multiple infractions of this rule may result in a disqualification at the discretion of the referees.
  • 3.4.5 A robot may not intentionally contaminate the playing field or an opponent's robot with lubricants or other debris.
  • 3.4.6 Robots may only be designed and built after the initial kickoff event.
• 3.5 Building Constraints
  • 3.5.1 Each team will be expected to use parts only from the Vex Kit unless specified on the additional materials list below.
  • 3.5.2 Modifications are permitted to the mechanical parts of the kit. Teams may NOT modify any of the kit electronics or motors. Modification of items on the additional materials list is permitted.
  • 3.5.3 Teams may use any 7.2V battery, but only one battery may be used on the robot at a time.
  • 3.5.4 Robots may use any Vex parts that come in a Dual Control Starter Bundle, any additional publicly available Vex mechanical parts (metal, wheels, treads, hardware, etc.), and any items on the additional materials list. Motors, servos, pneumatics, and sensors are not considered mechanical parts. The total retail cost of items used on the robot which are from the Additional Materials list or are non-mechanical Vex parts must not exceed $250. This $250 does not include the price of one Dual Control Starter Bundle (or the equivalent components), batteries, a second radio receiver or radio controller, and crystals.
  • 3.5.5 Teams may purchase pneumatics kits, provided it is equivalent to any kits or portions thereof shown at http://www.vexlabs.com/vex-robotics-pneumatic-parts.shtml and are within the robot budget per rule 3.5.4. Cost for incomplete Vex Labs pneumatics kits may be adjusted accordingly.
• 3.6 Materials
  • 3.6.1 Any amount of materials in the Additional Materials List will be allowed provided the total costs of all items on the robot is within the budget specified in 3.5.4.
  • 3.6.2 Additional Materials List
    • 3.6.2.1 Plastic sheet, up to 0.25 inch thick
    • 3.6.2.2 Aluminum or steel sheet, up to 0.125 inch thick
    • 3.6.2.3 Any aluminum, steel, or plastic round shaft or tubing up to 0.5 inch diameter
    • 3.6.2.4 Any bearings
    • 3.6.2.5 Plywood or wood up to 0.5 inch thickness
    • 3.6.2.6 "Foam rubber" up to 0.75 inch thickness
    • 3.6.2.7 Cardboard or foam-board
    • 3.6.2.8 String or twine
    • 3.6.2.9 Any springs or elastic bands (must be designed to release energy no faster than it was input)
    • 3.6.2.10 Fasteners, washers, and adhesives (used as such). You may not use adhesive tape (duct tape, electrical tape, etc) as a fastener or structural material
    • 3.6.2.11 Lubricants used to reduce friction within parts of your robot
    • 3.6.2.12 Non-functional decorations
    • 3.6.2.13 Paper, plastic-wrap, aluminum foil, fabric or any paper or cloth-like material
    • 3.6.2.14 Any sensors
    • 3.6.2.15 Any Vex or Robovation motors, servos, or pneumatic components.
  • 3.6.3 Materials that are not official Vex materials, or are not listed as approved additional materials must be approved on the official Savage Soccer Forum (www.wpi.edu/~savage/Forum). Robots that attend the competition with unapproved materials on their robot will not be given approval at the event and will not pass inspection until the offending materials have been removed.
• 3.7 Energy Sources
  • 3.7.1 The energy used by the devices in the competition must come solely from:
    • 3.7.1.1 A change in altitude of the center of gravity of the device
    • 3.7.1.2 Energy stored by deformation of any approved materials.
    • 3.7.1.3 Electrical energy delivered by the battery to the electronics and motors provided with the kit.
    • 3.7.1.4 Pressure stored in the pneumatics system not to exceed 100 psi.
• 3.8 Electronics
  • 3.8.1 Teams must keep clear and easy access to their robot controller, specifically the power switch. The indicator lights on the front of the controller must also be clearly visible.
  • 3.8.2 Teams must keep clear and easy access to the crystals in their robot receiver. Crystals will need to be exchanged quickly prior to each match. Inspectors or referees may request a team move the receiver to provide easier access before they are allowed to play.
  • 3.8.3 Crystals will not be allowed for use in the pit. Teams wishing to operate their robot in the pit must do so using tether only. Tethers for Vex are the telephone cables which connect the handset to the base.
  • 3.8.4 Prior to each match, teams will get a crystal set from the Field Captain. The crystals must be returned before the team leaves the field at the end of the match.
    • 3.8.4.1 Multiple infractions of 3.8.4 may lead to a disqualification at the discretion of the head referee.
  • 3.8.5 All teams are required to program their robot using the template provided on the resources page.
  • 3.8.6 Teams are not permitted to use the VEX-Net system.

4. Alternatives for Game Play (for events with less than 12 teams)

• 4.1 Play the game without coalitions in a one vs. one format
• 4.2 For a less expensive field, change the ball distribution to 10 red balls, 10 blue balls and 16 white balls
• 4.3 If necessary, 40mm ping pong balls may be substituted

Maintained by savage@wpi.edu
Last modified: Nov 11, 2009, 20:05 EST