• NC Gravity Games
2023 Official Gravity Game Rules

Please ensure that all members of your team, coaches, mentors, etc. thoroughly read and understand the entire Official Rules document.  It is your responsibility to be familiar with all rules, and comply with the rules as written.

Check the 2023 NC Gravity Games FAQ frequently! The FAQ can be found online at: ncgravitygames.com/faq. This is where clarification will be posted for specific Official Rules questions received from teams.

About the Gravity Games

With funding from Google Inc. (“Google”) in cooperation with Appalachian State University, Morehead Planetarium at UNC Chapel Hill, and the City of Lenoir, the 2023 NC Gravity Games (the “Competition”) will provide students from elementary through high school, college/university, and corporate competitors an opportunity to design and construct cars powered by gravity, and compete against other teams for the fastest time.

The event will be held on Saturday, April 29, 2023 from 7:30 a.m. to approximately 3 p.m.

Objectives

  • To have a fun, educational, inspirational, and competitive event that allows hands-on engineering
  • To enable students and STEM professionals to interact
  • To unite members of the community in an environment of fair competition and celebration
  • To develop an engaging competition and event that can be replicated for the future

Mission Statement

The 2023 NC Gravity Games strives to promote STEM (Science, Technology, Engineering, and Mathematics) with real-life application through construction and competition of a downhill derby-type racing event. The 2023 NC Gravity Games foster community engagement through sponsorship and will award prizes to the winning teams. The Competition focuses on the design, construction, and racing of a potential energy powered vehicle, on a downhill course.

Judging Committee

  • The Judging Committee will be comprised of representatives from Google and Appalachian State University. The Judging Committee will be responsible for inspecting each car, participant, and race track for adequate safety and security. The Judging Committee has the final say on whether or not one may participate in the Competition.
  • The Judging Committee has the sole discretion as to whether a violation of these Rules will result in disqualification of a participant and/or team.

Registration

  • The deadline to register is midnight EDT on March 17, 2023.
  • Teams must arrive on event day ready to compete in the same category that they registered in. Teams can not change their car registrations on event day. For example, if a team is registered in the engineering car division and arrives with a kit car, the team will not be allowed to compete.
  • A school/organization/coach may register a maximum of 2 kit teams. There is no limit for engineered or challenge teams. 
  • While more than 5 people are allowed to work on a car, prizes will be provided to a maximum of 5 team members. Students may only compete with one team per division.
  • Registration is first come, first serve. Once registration is full for a division, additional entries will be considered alternates in case a team withdraws from the competition.

Parental Consent/Participation Agreement

  • Participants ages 7-17 (on the day of the Competition at registration) are required to have a parent or legal guardian sign a Participation Agreement on the minor’s behalf in the form attached to these Rules as Attachment 1. (Download below.)
  • All participants ages 18 and over (on the day of the Competition at registration) must have a signed Participation Agreement in the form attached to these Rules. (Download below.)

Conduct

  • Participants must not use, possess, or distribute alcohol, tobacco, or drugs, with the exception of those prescribed by a physician specifically for that person.
  • Verbal or physical abuse and/or unsportsmanlike conduct will not be permitted, whether directed towards another participant, official, and/or spectator.
  • No firearms will be permitted on the race course or staging/support areas.
  • Competitors will not attempt to gain an unfair advantage over another participant.

Attire

  • Participants must wear adequate foot protection covering sole, toe, and heel while racing.
  • Participants must wear CPSC or ASTM certified protective helmets in their proper position on the head. A helmet approved for bicycle, derby, or motorcycle use is allowed as long as they meet CPSC or ASTM standards.
  • Headwear must be inspected and cleared by the Safety Committee.
  • Participants must wear adequate and appropriate clothing. No loose fitting or dangerous attire will be permitted. You might also want to consider protective clothing as well, such as a leather jacket and knee/elbow pads.

Divisions

Kit

A race for kit cars powered by gravitational energy. Any student from ages 7-14 on the date of the race is welcome to participate. 

    • Age: team members must be between 7 and 14 years old on the day of the race
    • Weight: The assembled car, weights, wheels, safety equipment and driver cannot exceed 200 lbs. for "Stock" kits and "Super Stock" kits. Any vehicles or car/driver combos that exceed this weight will be disqualified. Please note: The Super Stock weight restriction is lower than the specified maximum and standard weight limit for this category. We have adjusted this rule to eliminate the weight advantage for Super Stock kits.
    • Design: Cars must be based on either the All-American Soap Box Derby (“AASBD”) “Stock”, “Super Stock” (design type) kits ONLY, using Z-Glass wheels; a picture of these types of designs can be found at this website: http://www.soapboxracing.com/ All AASBD kit cars must be constructed according to the manufacturer's specifications and permitted modifications, which are outlined for each kit size:
      • Stock - http://www.soapboxderby.org/media/128298/stock-car-plans.pdf
      • Super Stock - http://www.soapboxderby.org/media/128299/super-stock-car-plans.pdf
    • Teams: There will be a maximum of 32 teams in this category. Registration is first come, first serve. Registration will be accepted beyond the first 32 teams, but will be listed as alternates in the order in which registration is received. The NC Gravity Games is focused on encouraging teams to develop and progress to more engineering-focused categories as they mature. As a result, a given organization / school / coach may have only two entries in the Kits Only category. Students may only compete with one team in this division.

Engineered

A race for "scratch-built" cars, not based on any pre-made kits, powered by gravity

    • Age: team members must be between 10 and 25 years old to participate
    • Weight: The assembled car, weights, wheels, safety equipment and driver cannot exceed 300 lbs.
    • Design: Entries must be primarily constructed by team members. For example, taking a pre-built go-cart chassis and putting wheels and a custom body on it would not be a valid entry.
      • Entries based substantially on AASBD kit cars are not permitted.  Kit entries may utilize Z-glass wheels and axles from an AASBD kit, but not the body and/or wooden base platform.
      • Judges will assess the construction of each Engineered entry. Vehicles that do not meet basic safety or structural requirements (e.g. it must be strong enough to stay together during the race, and not be dangerous for the driver), or those that are composed mostly of pre-built components may be disqualified.
      • Designs which place the driver’s head in front of their body (e.g., laying face down and head-first as in a skeleton sled), are not permitted.
      • Due to stability concerns, three-wheeled designs are not permitted. Cars must have a minimum of four wheels in contact with the ground at all times.
      • If the driver is not contained within an enclosed vehicle, there must be safety restraints (e.g. seat belts, harnesses) to hold the driver in place, and these restraints must be sturdy enough to hold in the case of a collision. The driver must also wear suitably protective clothing.
    • Additional requirements for materials and car eligibility may be found below.
    • Engineered car designs (drawings, pictures, etc) must be submitted beforehand to Michael Briley (brileymm@appstate.edu) and Leah Sherman (shermanlb@appstate.edu) to ensure compliance with safety rules. Michael and Leah are also the contacts for questions about your design, components, and eligibility.
    • Teams: There will be a maximum of 48 teams in this category. Registration is first come, first serve. There is no limit to the number of entries in this division from any given school/organization/coach. 

Challenge: Change in Motion

An engineering challenge to design and construct a vehicle that uses only the power of gravity to change its appearance during the course of the run. Examples of this can include, but are not limited to: color, shape, banners, sails, flags, lights.

    • Age: team members must be between 10 and 25 years old to participate
    • Weight: The assembled car, weights, wheels, safety equipment and driver cannot exceed 350 lbs.
    • Design: The specific engineering challenge is to design and construct a vehicle that “transforms” during the race. The car must use power generated by downhill movement using some mechanical component. It is not enough to simply use wind or person power, though these may supplement existing systems that capture power generated by gravity. Examples of transformations include color/light change, vehicle shape change, or additions (flags, banners, wings). Each car can then return to the original configuration after passing through the finish line.
      • One winner will be the fastest car that is able to successfully transform during the race.
      • One winner will be for design and engineering, measured along the pillars of execution, elegance, complexity, and magnitude of change, as determined by a panel of judges
      • There will be 2 winning categories in the challenge:
      • Entries based substantially on AASBD kit cars are not permitted.  Kit entries may utilize Z-glass wheels and axles from an AASBD kit, but not the body and/or wooden base platform.
      • Judges will assess the construction of each Challengeentry. Vehicles that do not meet basic safety or structural requirements (e.g. it must be strong enough to stay together during the race, and not be dangerous for the driver), or those that are composed mostly of pre-built components may be disqualified.
      • Designs which place the driver’s head in front of their body (e.g., laying face down and head-first as in a skeleton sled), are not permitted.
      • Due to stability concerns, three-wheeled designs are not permitted. Cars must have a minimum of four wheels in contact with the ground at all times.
      • If the driver is not contained within an enclosed vehicle, there must be safety restraints (e.g. seat belts, harnesses) to hold the driver in place, and these restraints must be sturdy enough to hold in the case of a collision. The driver must also wear suitably protective clothing.
      • Additional requirements for materials and car eligibility may be found below.
      • Challengecar designs (drawings, pictures, etc) must be submitted beforehand to Michael Briley (brileymm@appstate.edu) and Leah Sherman (shermanlb@appstate.edu) to ensure compliance with safety rules. Michael and Leah are also the contacts for questions about your design, components, and eligibility.
    • Teams: There will be a maximum of 32 teams in this category. Registration is first come, first serve. There is no limit to the number of entries in this division from any given school/organization/coach.

Open

Teams that wish to race but that do not meet the requirements for other divisions are welcome to sign up for the open division.

    • Age: There is no maximum age limit for team members (meaning adults can participate)
    • Weight: There is no maximum weight, although the car must be able to be loaded onto the starting ramp and be able to brake to a complete stop at the bottom of the hill before hitting the backstop.
    • Design: Entries in the Open division can be designed and built from scratch or based on a kit.
      • Judges will assess the construction of each Open division entry. Vehicles that do not meet basic safety or structural requirements (e.g. it must be strong enough to stay together during the race, and not be dangerous for the driver) may be disqualified.
      • Designs which place the driver’s head in front of their body (e.g., laying face down and head-first as in a skeleton sled), are not permitted.
      • Due to stability concerns, three-wheeled designs are not permitted. Cars must have a minimum of four wheels in contact with the ground at all times.
      • If the driver is not contained within an enclosed vehicle, there must be safety restraints (e.g. seat belts, harnesses) to hold the driver in place, and these restraints must be sturdy enough to hold in the case of a collision. The driver must also wear suitably protective clothing.
      • Additional requirements for car eligibility can be found below.
    • All cars and drivers must pass a safety inspection, and any non-kit car designs need to be approved by the safety committee in advance.
    • Maximum dimensions are the same as the engineering and challenge divisions.
    • This is a non-competitive division, meaning teams are not eligible for prizes and will not race in an elimination bracket. The Judging Committee will schedule time trials and/or head-to-head races based on the number of participating teams.

Rules Table

Materials

  • All cars and material components are subject to inspection and subsequent disqualification by the Safety Committee if deemed harmful or potentially dangerous.
  • Please feel free to contact Michael Briley (brileymm@appstate.edu) and Leah Sherman (shermanlb@appstate.edu) if you have any questions.
  • No chemical or nuclear engines allowed.
  • No pre-energized potential energy sources allowed (other than gravity).

Car Eligibility

  • Gravity may be the only propulsion source in the Kits Only and Engineered divisions.
  • No human powered cars or engines will be permitted. Other than acceleration due to gravity, no external propulsive energy may be added to the drive system after the start of the race.
  • Forbidden propulsion systems: 
    • Chemical engines (gasoline, diesel, etc.)
    • Any electrical power source 
    • Potential energy systems (besides gravity)
    • Nuclear (fission or fusion)
    • Any combustion-based motor
    • Pedals (human-powered)
    • Animal powered (mules, dogs, hamsters)
  • For all divisions, team members must take part in the construction of his or her car; an adult mentor is permitted to assist in the construction of the car, but the majority of the work should be completed by the team members. The Judging Committee will have sole discretion to evaluate and disqualify obvious violations of this rule.
  • Designs which place the driver’s head in front of their body (e.g., laying face down and head-first as in a skeleton sled), are not permitted.
  • Due to stability concerns, three-wheeled designs are not permitted. Cars must have a minimum of four wheels in contact with the ground at all times.
  • Each car must be able to steer both left and right (the track is a crowned road and the left lane driver will need to steer right, and the right lane driver left, in order to maintain a straight path). Steering must also be smooth. Stops should be installed if necessary to prevent oversteering.
  • Steering may not be performed via the feet.
  • Tiller steering is not allowed.
  • All cars must have a braking system capable of slowing the car to a smooth, short and safe straight line stop without damaging the road surface. Braking tests will be conducted during inspection to ensure they are sufficient. Cars without sufficient stopping power will not be allowed to race.
  • All brakes must be symmetrical (i.e. either centered in the car or balanced on both sides).
  • Brakes must be able to be actuated without letting go of steering controls. Hand brakes are discouraged and if used, they must be fully operated using a single hand. Two-handed independent brakes are not allowed. 
  • Cable links used in steering and braking systems must be secured and not slip under stress. Turnbuckles and other adjusting hardware must be lock-wired in their final positions. The use of ropes in steering and braking systems is strongly discouraged and may result in disqualification, especially if any slack is present
  • Cars cannot have any objects or devices in the driver area that poses a threat to the driver. There should be no exposed sharp edges or points. Any edge that may contact the driver must be smooth.
  • Cars cannot pose a hazard to those around it.
  • Teams are encouraged to decorate and/or paint their car as long as this does not break any of the Rules nor interfere with the safety of the participant or other competitors.
  • Modification, alteration, or tampering with the car after inspection by the Safety Committee is only allowed with the approval and the supervision of the Safety Committee.
  • Each car and driver must be inspected and approved by the Safety Committee before racing. The Safety Committee, in its sole discretion, may postpone, restrict, or disqualify any participant or car deemed to be unsafe to race. The Safety Committee does not need to provide explanation for disqualification and has the final say in eligibility of all cars, participants and teams competing in the Competition.
  • Note that It is important that the car can be driven repeatedly without steering and brakes adjustment.
  • All cars should be tested well before race day to ensure the steering and brake mechanisms operate smoothly and reliably over multiple runs. Test the whole car on a sloping surface. Make certain, through testing, that the drivers can safely operate the car.

Racing

  • Each car must accelerate from a standstill by gravity only without the aid of external propulsion devices including human power.
  • Participants must remain in the car until all cars have crossed the finish line.
  • Participants may not interfere with other cars or drivers.
  • If the car is not drivable at the time of the race, the round will be considered a forfeit, unless judges approve an exception.

Race process/heats

Kits-Only Division:

  • The Kits-Only division will be run using a bracket system with initial time trial.
  • The first round will be a time trial. The competitors will then be placed into a tournament bracket.
  • Lane assignment will be random.
  • The second round will be a two car head-to-head race, determined by the time trial (first) round. The victor will move on to face another second round victor.
  • The Competition will progress in a single-elimination style bracket until the final two cars remain.
  • The final round will be a best two-out-of-three competition run head-to-head. There will also be a third-place race.
  • The competition committee will provide teams an estimated race schedule at check-in and make announcements over loudspeakers to inform teams when they will need to be ready to race.. Teams that are not in place at the start of their heat will receive a loss for that heat, unless judges approve a delay.

Engineered Division:

  • The Engineered division will use a bracket system with initial time trial. 
  • The first round will be a time trial. The competitors will then be placed into a tournament bracket.
  • Lane assignment will be random.
  • The second round will be a two car head-to-head race, determined by the time trial (first) round. The victor will move on to face another second round victor.
  • The Competition will progress in a single-elimination style bracket until the final two cars remain.
  • The final round will be a single competition run head-to-head. There will also be a third-place race.
  • The competition committee will provide teams an estimated race schedule at check-in and make announcements over loudspeakers to inform teams when they will need to be ready to race. Teams that are not in place at the start of their heat will receive a loss for that heat, unless judges approve a delay.
  • NOTE: Depending on the number of applicants, the first round may be eliminated and the pairings determined by random drawing. Teams will be notified of this decision soon after the registration is closed.

Challenge Division

  • The Engineering Challenge division will run based on a bracket system with initial time trial. 
  • The first round will be a time trial. The competitors will then be placed into a tournament bracket.
  • Lane assignment will be random.
  • The second round will be a two car head-to-head race, determined by the time trial (first) round.
  • The Competition will progress in a single-elimination style bracket until the final two cars remain.
  • The final round will be a single competition run head-to-head. There will also be a third-place race.
  • The competition committee will provide teams an estimated race schedule at check-in and make announcements over loudspeakers to inform teams when they will need to be ready to race. Teams that are not in place at the start of their heat will receive a loss for that heat, unless judges approve a delay.

Course

  • The Kits Only, Engineered, and Engineering Challenge division races will all run down Ashe Avenue, starting at Church Street, heading East.
  • Electronic sensors will provide precision timing for each race.

Inspections

All teams must pass weight and safety inspections prior to racing. Judges may require teams to be re-inspected at any time.

  • Weight
    • Once the official inspection and weigh-in is completed the weights cannot be changed, unless another driver is driving. It is the responsibility of the team to ensure the weight does not exceed the limit after the initial weigh-in. The cars, with driver, will be re-weighed at the bottom of the hill following each run. If overweight, the car will be disqualified.
  • Safety
    • Judges will visually inspect the car to ensure rules compliance. The driver must then demonstrate the ability to steer the car both right and left and safely brake. 

Awards

  • There will be awards given to the 1st, 2nd, and 3rd place team in each division for speed based on bracket results. Speed is based on the first car with a participant to cross the finish line in each race. See also “Racing” and “Heats" within these Official Rules.
  • Additional awards may be given on the day of the competition based on the judges’ discretion.
  • Final judging will be performed on the day of the event.

Competition Timeline

  • Registration closes March 17, 2023
  • Engineered and Challenge division designs due March 29, 2023
  • Race-day instructions and additional information will be distributed to all teams 2 weeks before the event dependent on the number of teams competing.
  • Check-in begins at 7:30 a.m. April 29, 2023.
  • Awards to follow after completion of all races on April 29, 2023.

Related Files

2023 Participation Agreement (Waiver)

2023 Design Rubric