2015-16 Challenge Rules



The objective of the Sample Return Robot Challenge is to develop new technologies or apply existing technologies in unique ways to create robots that can autonomously seek out samples and return to a designated point in a set time period. Robots will be required to navigate over unknown terrain, around obstacles, and in varied lighting conditions to identify, retrieve, and return these samples.

To understand the tentative schedule and logistics for the Level 1 and Level 2 challenge, teams should consult the Competition Logistics page on the official challenge website.


The final interpretation of all rules is at the discretion of the judges.


R1.       For the purpose of this challenge and rule set, a robot is defined as all mechanical and electrical components, except the home beacon and pause switch, provided by the team in order to successfully compete in the challenge. This includes but is not limited to motors, batteries, computers, decorations, required safety switches, and items that do not remain attached for the entire challenge.

R2.       Robot may not exceed 80kg.

R3.       Robot may not exceed 1.5m x 1.5m x 1.5m in its starting configuration. Robot may not exceed 4m vertically during the challenge attempt.

R4.       For the safety of event officials on the course, robots may not travel over the surface of the course faster than 2 meters per second (walking speed). Purposeful or sustained exceeding of this speed limit is subject to disqualification.

R5.       Strategies or designs aimed at the disruption, destruction of, or damage to an opponent’s robot or the field is not in the spirit of the challenge and will not be allowed. This includes intentionally leaving objects on the course of similar shape and color to samples. Violations of this rule may result in disqualification at the discretion of the judges.


R6.       Each team may provide a Home Beacon and place it on the designated platform adjacent to their starting platform. A Home Beacon can be any combination of electro-mechanical items provided by the team that assists their robot in identifying their starting platform and complies with the weight, size, expansion, and power limitations listed in rules Section 1.1.

R7.       Home Beacon must comply with Section 1.3 Disallowed Technology.

R8.       Home Beacon may not exceed 15kg.

R9.       Home Beacon may not exceed 2m x .43m (width x depth), can be no more than 2m in height at the start of the challenge attempt.

R10.     Home Beacon may not contain any parts that are powered to repeatedly move outside the vertical projection of the home beacon platform.

R11.     Home Beacon may contain its own power and is not subject to the pause and E-Stop compliance rules. It must have no more than one clearly labeled off switch and will only be activated by an event official during a challenge attempt due to safety concerns (this will not be considered an E-Stop).


R12.     Each robot must have space to carry a required payload of .1m x .1m x .25m and approximately 5kg mass easily accessible to event officials. Each robot must provide one flat, .1m x .25m area on the outermost surface of the robot to attach the payload. This payload will be provided, along with the means of attachment, to each team by the event and is not included in the robot mass or size.  At the discretion of the judges, portions of the payload may be distributed across several robot components and the home beacon.

R13.     The required payload may contain a strong magnetic source, frequency jammer, and/or WiFi encryption device to disable any inadvertent usage of prohibited signals and technologies.


R14.     As one of the goals of this competition is to develop robots, processes, and technologies that could be implemented in a lunar or Martian environment, the robot and any related technology cannot employ fundamental physical processes, gases, fluids, or consumables that would not work in such environments.

    • Specifically disallowed technologies and components include:
      • Sensors that rely on the earth’s magnetic field
      • Ultrasonic or other sound-based sensors
      • Earth-based or earth orbit-based radio aids (e.g. GPS, VOR, cell phone)
      • Open circuit pneumatics
      • Air-breathing systems
      • Any communication between robot components or between the robot and the home beacon that does not comply with FAA and/or FCC regulations.

R15.     Exceptions to R15 include:

    • Fans for the purpose of cooling only (including cooling motors)
    • Propulsion systems for sustained vertical flight via tethered flying apparatus

R16.     Hazardous materials that pose a threat to teams, spectators, event officials, the environment or other robots are disallowed. Specifically, any Class 1, 3, 4, 5, 6, or 7 hazardous materials are strictly prohibited.


R17.     Each robot must have the following switches or indicators, provided by the team, and they must be easy to identify by the judges.  Additional guidance for spawn robots can be found in R18:

    • Mechanical E-stop: The E-stop button must be push-to-stop, red in color and a minimum of 2.5 cm in diameter. It must be easy to identify and activate safely from the rear-aspect, even if the robot is moving. For robots with a starting height over .75m, it must be located on the center-rear stable surface of robot at least .75m from ground, never to exceed 1.5m above ground. For robots with a starting height .75m or under, the switch must be located on the center-rear, top-most stable surface of the robot, never to exceed 1m above the ground. The E-stop must be hardware based and not controlled through software. Activating the E-Stop must shut down all robot power.
    • Pause Switch: The wireless Pause must be effective for a minimum of 30 meters. For the safety of event staff and spectators, activating the Pause must bring all motion of all robot components to a complete stop within 1 second of activation for non-spawn robots. Exceptions to the pause rule (like motion of internal robot components) may be considered solely at the judges’ discretion. The team may present exception requests at any time for technical review and provisional approval. The judge committee will make final approval of all exemption requests on-site upon demonstration of the pause sequence. When a robot is paused, its official event clock will also be paused.
    • Safety Light: Each robot must have an easily viewed indicator light that is turned on whenever the robot power is turned on. The light must be amber/orange in color, solid when the robot is paused, and flashing at a rate of approximately 1Hz when the robot is powered and enabled.

R18.     If a robot splits into multiple components that traverse the course (known as spawn), the following applies:

    • There must be one pause switch supplied for each spawn, and both the pause switch and spawn must be clearly labeled to indicate which spawn the switch activates.    Activating one pause button must pause motion of the designated spawn within 1 second.
    • There must be an E-stop button on every spawn located .75m above the ground or on the top-most stable surface of the robot, whichever is lower. Activating a spawn E-stop must stop power to that spawn.
    • There must be a safety light on each spawn.


In order to be eligible to win the Challenge, teams must successfully submit all required documentation, pass all inspections, and complete the Level 1 and Level 2 portions of the Challenge.  Level 1 will be considered a qualifying portion of the Challenge in which all competitors will be given the opportunity to compete prior to attempting Level 2.  Teams who successfully complete Level 1 will be given the opportunity to attempt Level 2.

If a Team has previously accepted Level 2 auto-qualification status, the team will not be given a Level 1 attempt opportunity and is ineligible to win additional Level 1 prize money.

2.1 LEVEL 1

C1.       For a robot to have successfully completed Level 1, one undamaged, pre-cached sample and one easy sample (described in section 3.1) must be autonomously returned to the starting platform within the 30-minute time limit..

C2.       Teams will be given as many attempts at Level 1 as reasonable, with each team being guaranteed two attempts.

C3.       Teams who successfully complete Level 1 will be given an opportunity to compete in Level 2.

C4.       All teams will be given access to repair, modify and update their robot and home beacon between their Level 1 attempt(s).

2.2 LEVEL 2

C5.       Determination of the winners and final prize allocation will be determined by the:

    • Total number of distinctly different samples collected (maximum 10)
    • The point values of those samples

C6.       For a robot to have successfully completed Level 2, it must autonomously return at least two undamaged samples, including the pre-cached sample, to their starting platform within the two-hour time limit.


C7.       If at any time during the challenge attempt a sample comes in contact with another sample (violating “sterile handling”) neither sample will count towards that robot’s score.

C8.       Only samples contained within the vertical projection of the starting platform (not including the ramps) when the event official signals the end of a team’s run will count.

C9.       Samples must comprise at least 50% of the mass of any items returned to the starting platform (excluding the starting mass of the robot).

C10.     Any samples contained within the robot at the end of the run must be easy and obvious to remove by an event official so that sterile handling (C7) and sample mass vs. collected mass (C9) can be determined. Team members will not be allowed to remove or assist in the removal of samples from their robot.

C11.     The number of successfully retrieved samples in the starting platform will be counted at the end of the challenge attempt only.


Prior to each Level, teams must submit all required documentation and deliverables required by the judge committee. Failure to comply could result in disqualification. Detailed list of deliverables is provided in the “Critical Deadlines and Documentation” section.


C12.     Each team must complete their own pre-inspection to validate the legality of their robot and to provide clear documentation of how event officials interact with the robot.  Clear documentation includes, but is not limited to, written startup and safe shutdown procedures.

C13.     Prior to the start of the Level 1 challenge, judges will review each team’s robot for compliance and sign off on the pre-inspection. Teams may continue to work on and modify their robots throughout the Level 1 challenge provided they continue to remain in compliance with all rules.

C14.     During Level 1 pre-inspection, teams must demonstrate autonomous control of their robot for the judges by:

  • Placing the robot at a designated starting point or starting platform and booting it up per their documented startup procedure,
  • Traversing to the pre-cached sample
  • Collecting the pre-cached sample, and
  • Returning the sample to a designated area.

C15.     After a team successfully completes Level 1, the judges will conduct an official inspection. Teams who do not pass this inspection will be disqualified from their successful attempt and must bring their robot into compliance prior to retrying Level 1 (time permitting).


C16.     Prior to the start of Level 2 all robots and home beacons must be impounded.

C17.     Once impounded, teams will not have access to their robots or home beacons to make any mechanical, electrical, or programming modifications until it is placed on the starting platform.

C18.     Teams are allowed to keep their batteries and chargers outside of the impound area and bring their batteries into impound during the inspection period. All batteries not kept in impound are subject to re-inspection.

C19.     Teams who leave their batteries and chargers in the impound area will be allowed to install them during the inspection period. A team member may be granted permission to access their batteries in impound, solely for charging purposes, by a judge and under the direct supervision of an event official.

C20.     Each robot will be impounded from the start of Level 2 until all teams have completed Level 2.

C21.     In Level 2, at the end of inspection, teams will install their batteries if required, place their robot on the starting platform, and secure their robot to the starting platform in impound.

C22.     At the end of all challenge attempts, all successful robots are subject to a Critical Inspection before the prize distribution is determined.


C23.     The starting platform is made of wood with a plywood top surface 2m x 2m in size.

C24.     The starting platform will have a designated back, center, and area for robot placement. The robot must be fully contained within the marked starting area and the home beacon platform must be placed with its long edge adjacent to the back of the starting platform.

C25.     When the starting platform is placed on the field, the robot will be approximately 15cm above the field surface.

C26.     Ramps, approximately 15 degrees in slope, will be placed on the front and sides of the platform to assist in a smooth transition between robot and platform. Ramps are not considered part of the starting platform (C6).


C27.     An event official will transport the platform, robot, and home beacon using standard ground transportation operations, like a forklift. Robots must be secured to be able to endure transport.

C28.     Six flush tie-down connections will be available for teams to use to secure their robot to the platform. The event will have a limited number of common ratchet straps and rope ratchets on site for use.

C29.     Teams may secure their robot through other means, although they are not allowed to make any modification to the platform surface.

C30.     Once placed on the field, an event official will be responsible for removing all securing devices from the robot. In the inspection, teams must clearly describe the removal process of any securing devices used.


C31.     During the challenge attempt, event official(s) may walk approximately 3 meters behind the robot with the designated pause switch. They will monitor safety hazards, and rule violations as well as document the challenge attempt. Additional challenge officials may be located on the course, but above the height of the boundary fencing (E8) or a minimum of 50 meters from the robot.

C32.     If a robot’s pause switch is activated by the event official for safety concerns or to evaluate a rules violation, that robot’s official event clock will be paused and restarted when the robot is unpaused.

C33.     Teams will have 10 minutes of Setup Time prior to their run. During that time the team must place their robot on the starting platform. For Level 2, teams must also secure their robot to the platform during this time.

C34. During their Setup Time, teams may interact with their robot in any way while it is on the starting platform. Teams must also setup their home beacon (if applicable). All team interaction with the robot and home beacon must take place under judges’ supervision. When the team is complete with their Setup Time, the home beacon must be powered on (if applicable) and the robot must be in a paused state.

C35. If the team does not complete their robot or home beacon setup and startup during the designated Setup Time, they may choose to use up to 10 minutes of their official competition run time to complete the setup. The official run clock will begin and it will be stopped only when the team indicates setup is complete or 10 minutes has passed. The team will have the remaining time on the official run clock to complete their attempt.

2.7.1 LEVEL 1

C36.     The Level 1 challenge course will be made available on a first-come, first-serve basis for teams throughout the challenge day, with the exception of the final time period where slots will be scheduled to guarantee each team has a minimum of two attempts during the challenge.

C37.     Multiple Level 1 courses will be available each with its own starting platform and samples. All attempts will be made to ensure the courses are virtually identical. Teams will be randomly assigned to a course when they are ready for their attempt.

C38.     Teams will place their robot on the starting platform and their home beacon on its platform.  The platforms will face the same direction for all teams, as noted in the Level 1 map.

C39.     Once the robot setup is complete on the platform and during the Level 1 competition runs, human-to-robot communication is restricted to event officials until the end of the attempt. They will communicate via E-stops on the robot and via the wireless pause switches.

C40.     During the team’s challenge attempt, all team members may only use electronic devices (laptops, cell phones, cameras, etc) under the direct supervision of a judge to ensure there is no robot tele-operation.

C41.     During the competition run, the robot may only communicate with items in the starting platform or roving area that were included in the robot mass as well as their home beacon and pause switch(es).

C42.     To start the official challenge attempt, an event official will trigger the unpause switch of the robot.

2.7.2 LEVEL 2

C43.     Based on their weight (lightest to heaviest), each team will be allowed to select their order in the competition and approximate start time for Level 2. This selection will occur on the first day of the Level 2 competition prior to impound.

C44.     At the start of their setup time, the Team Leader will randomly draw and be informed of an orientation and starting zone. Heading is guaranteed within 5 degrees of the selected value and the center of the starting platform will be placed within 2m of the center of the selected started zone.

C45.     An event official will deliver the home beacon and starting platform with robot to one of three designated starting zones. When the platform is delivered to the starting zone, an event official will direct its orientation and placement, rotating the front of the platform to the team-drawn heading (up to 60 degrees clockwise or counterclockwise from the reference point marked in the satellite image) (Section 3).

C46.     Once all securing apparatus are removed, an event official will trigger the unpause switch of the robot and the official time clock for that robot’s challenge attempt will be started/resumed.

C47.     From the start of the Level 2 runs until their team’s challenge attempt, all team members of Level 2 competing teams will be sequestered in a designated area and will not be allowed to view other teams’ Level 2 attempts. During this time, the judges may request that team members relinquish personal electronic devices to ensure no information about the Level 2 course setup is acquired. LEVEL 2 COMMUNICATION UPDATE PERIODS

C48.     As one of the goals of the competition is to simulate the real world operation of robots on the moon or Mars, teams will be given limited opportunities in Level 2, called Communication Update Periods, to provide new information or code to their robot to correct or modify its behavior to aid in the success of sample collection. The intent of these periods is to represent remote transmissions from earth to a robot in space.

  • During a Communication Update Period, teams may:
    • Download new code to the robot or home beacon
    • Verify the functionality of robot or home beacon components through electronic control only
    • Pause and unpause the robot

C49.     Prior to their challenge attempt, the team must designate which of their electronic devices will be used during the Communication Update Period. Those electronics will be kept with the team during their challenge attempt. All other electronic devices must be relinquished to the judges. Any team member who does not wish to relinquish their electronic devices must return to the pit area for the duration of the team’s challenge attempt.

C50.     During the entirety of the team’s Level 2 challenge attempt with the exception of the Communications Update Period, team members may access ONE of these electronic devices referenced in C55 provided no transmission is being made to or from the robot or home beacon. This access will only be granted under the direct supervision of an event official.

C51.     Judges will offer a team a Communication Update Period at the following times:

  • At the expiration of the 15-minute inactivity clock (C66 Bullet 2-1)
  • At 20 minutes from the start, from the last official unpause of the robot at the end of the previous Communication Update Period, or from a team declining the use of a Communication Update Period.

C52.     Per rule C57, the judges will ask the team if they request to use a Communication Update Period and the team must answer immediately.

  • If the team requests to use the Period, the robot will be paused.
  • If a team declines to use the Period, the robot will not be paused and operation will continue.
  • In both of these cases, the official run clock will remain running.

C53.     During the Communication Update Period, the robot may not move more than 1m from where it initially was paused during the Communication Update Period.

C54.     At the end of the Communication Update Period:

  • Teams must terminate all communication with the robot.
  • The robot must be left in a paused state.
  • Once the team has terminated communication and the robot is ready to continue the challenge attempt, the official run clock will be stopped to allow judges to return to their viewing areas.
  • Judges will signal for an unpause of the robot. At that time, the official run clock and 15-minute inactivity clock will be resumed. Robots that triggered a Communication Update Period due to expiration of the 15-minute inactivity clock will be given a grace period of one minute for the robot to show signs of activity.


C55.     An event official may pause or unpause any robot any number of times during their challenge attempt for any length of time to evaluate safety concerns or rules violations.  When a pause is signaled, all followers on the course will activate all pause switches and the official run clock will be stopped.

C56.     Robots may be paused for safety considerations or if continued operation will likely cause significant damage to the robot or the field.

C57.     Robots may be paused to allow an event official to evaluate if an E-Stop condition has occurred.


C58.     An event official may activate each E-Stop on a robot once during a challenge attempt. Activation of all robot E-Stops means the robot’s challenge attempt is complete even though the time limit has not been reached.

C59.     Unless it is an offense that is subject to disqualification, E-stopped robots are still able to qualify and win prize money based on their performance prior to being E-stopped.

C60.     Robots are subject to ‘UNSAFE’ or ‘SAFE’ E-Stops.

  • UNSAFE E-Stops are situations where the robot or spawn is considered unsafe or there is an immediate safety threat at the event.  In this case, the E-Stop may be hit directly with no concern or consideration to its effect on robot or spawn components.  An UNSAFE E-stop may not always be preceded by a pause.  UNSAFE E-stop situations may include:
    • The robot or spawn contacts the outer boundaries of the roving area and would clearly continue past the boundary if left uninterrupted.
    • The robot or spawn poses an extreme safety hazard to event officials, spectators, or the environment.
    • The robot or spawn is found to be in violation of any of the rules.
  • SAFE E-Stops are situations where the robot or spawn may be operating ‘normally’, but nonetheless need to be disabled.  A SAFE E-Stop will always be preceded by a pause.  In the case of a SAFE E-Stop, the team may request, within reason, that the judges follow a special procedure to disable or shutdown the robot or spawn.  SAFE E-Stop situations may include:
    • The robot or spawn has shown no signs of activity for at least 15 minutes.
    • The robot or spawn has shown no signs of meaningful activity for at least 5 minutes and the Team Leader requests to end the operation of that spawn or the challenge attempt as a whole.
    • Continued operation of the robot or spawn will likely cause significant damage to itself or the field.
    • The robot or spawn is found to be in violation of any of the rules.


C61.     A robot and team may be disqualified from the competition for rules violation at any time prior to, during, or after a challenge run at the discretion of the judges.

C62.     Disqualified robots will not be allowed to participate in the challenge, continue with their challenge run, or win any prize money.


Teams will be provided limited topographical data of the roving area in advance of the competition to include maximum grades, types of surfaces, man-made structures to aid navigation, and large fixed features for orientation. A satellite image of the competition area will be provided to all competitors by 7-JAN-2016. This imagery will include at a minimum the location of the starting zones and the area of interests.

E1.       Competition will take place during daylight hours.

E2.       Continuation of the competition in the event of inclement weather will be at the discretion of the judges. Competitors should anticipate and prepare for the competition continuing in most situations except lightning.

E3.       Moving and stationary objects that are not part of the competition may be located outside but near to the orange border fencing and other borders. These objects may include but are not limited to spectators and automobiles.


E4.       Level 1 competition field is outdoors, over a large area, with flat terrain and limited obstacles. This competition field may have lines marked on the ground that are not relative to the challenge.

E5.       Some borders of the competition area may be marked with orange fencing no less than ½ meter tall.


E6.       Level 2 competition field is outdoors, over a large area, with both open rolling terrain and immovable obstacles (trees, large rocks, water hazards, etc).

E7.       The competition area for the robot during the Level 2 challenge attempt is approximately 80,000 square meters.

E8.       Orange fencing no less than ½ meter tall will mark the borders of the roving area. Examples of this fencing are available in the FAQ.


E9.       Samples will be placed on the ground throughout the roving area within marked areas of interest. They may be placed close to obstacles, both movable and immovable.

E10.     Each sample will have no overall dimension that is less than 1cm or exceeds 20cm.

E11.     Each sample will be no less than 100g and no more than 1kg.

E12.     One of each of the samples listed in E14 will be on the course during each Level 2 challenge attempt.

E13.     Samples are broken into three categories for the purpose of final prize determination. More details on some samples are available in the FAQ.

    • Pre-cached Sample
      • Represents a sample that has already been contained by a rover on the planet prior to your arrival and is awaiting collection.
      • A cylinder slightly under 8cm in diameter and 8cm in length
      • Has a standard hook interface
    • Easy
      • Rock, painted purple, with a major axis 10-12cm and a mass of 700-1000g
      • Rock, painted purple, with a major axis 10-12cm and a mass of 700-1000g
      • Rock, painted purple, with a major axis 10-12cm and a mass of 700-1000g
    • Intermediate
      • Rock, painted within the HSV range of 240-60, with a major axis 6-8cm
      • Rock, painted within the HSV range of 240-60, with a major axis 6-8cm
      • Rock, painted within the HSV range of 240-60, with a major axis 6-8cm
    • Hard
      • Non-ferrous metal object engraved with a unique, rectilinear, identifying mark #1
      • Non-ferrous metal object engraved with a unique, rectilinear, identifying mark #2
      • Non-ferrous metal object engraved with a unique, rectilinear, identifying mark #3

E14.     No two samples will be closer than 10 meters to each other within the roving area and all samples will be placed at least 1 meter from the boundary fencing.

E15.     At the end of a Communications Update Period, samples on the course may be shifted up to 5 meters in any direction.


Prize money will be distributed based on a pre-determined method described below. If some or all of the prize money is not distributed during the challenge, the challenge may be repeated, with or without modification, in the future.

Note that only one of each Technology Achievement Award, one Level 1, and one Level 2 prize is available to a team in a challenge year.


P1.       Teams that achieve certain technology milestones will be eligible for monetary awards independent of the prize money listed in sections 4.2 or 4.3.

  • Each team who arrives at the competition with a robot that successfully passes Level 1 pre-inspection by the posted deadline will receive $1000.


P2.       A pool of $50,000 will be equally distributed among all prize-eligible teams successfully completing Level 1 within the time limit, with a maximum of $5,000 per team.


P3.       The amount of prize money available to all competitors will be set by the top-scoring team who is eligible per the Prize Distribution Schedule in P8 and prize eligibility standards described in the Team Agreement.

P4.       The amount of prize money available to any individual team will be based on the ratio of their score to the top three scores of prize-eligible teams, and capped by the maximums allowed per the prize distribution schedule in P8. Examples of the prize money calculations are available in the FAQ.

P5.       Sample types are worth the following points:

      • Pre-cached sample – 1 point
      • Easy – 1 point
      • Intermediate – 2 points
      • Hard – 5 points

P6.       At the end of each robot run, the successfully retrieved samples will be counted and the score of each robot recorded. Robots will only receive credit for one of each of the 10 samples listed in section 3.3.

P7.       Once all robots have made their attempts, the top three scoring robots will be identified by the judges as eligible for prize money.

P8.       Prize Distribution Schedule (less any funds distributed for Level 1 or in previous challenge attempts):

      • 4-7 Points: $250,000
      • 8-12 Points: $750,000
      • 13+ Points: $1,390,000

P9.       In the case of a tie at Level 2, the following will occur:

  • If possible, only the top 3 performing teams will receive prize money.  In cases where this is possible, all 3 teams will receive a value based on their points scored.
  • If a tie requires more than three teams to receive prize money, the tied teams will split the available funds equal to a single team scoring that number of points
  • Additional explanation is available in the FAQ.