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Stylized Text: Batt Mobile Rules.

B.A.T. Mobile Challenge

The B.A.T. Mobile Challenge consists of two parts–design judging and a double elimination race.

Design Judging

Car Design Judging

Each team must submit their BAT Mobile to FSEC the day of the event. The car will remain impounded until the scheduled time when the racing begins. During impoundment, selected judges will review each car for its quality, precision, durability, design concept, and safety.

Design Document Judging

Each team must provide a Design Document for their car before being allowed to compete. The Design Document is not a daily journal. it is an engineering schematic.

The Design Document must include:

  • cover page
  • team member names
  • specifications of final vehicle (size, weight, wheel size, gear ratio, etc.)
  • component list--all parts purchased for your vehicle
    (including the name of the supplier and the price of the part)
  • design and assembly process
  • greatest obstacles (issues and problems encountered and modifications made)
  • any non team member assistance

The Design Document might include:

  • design drawings
  • electrical schematics
  • formulas and calculations used
  • photos taken periodically during construction process
  • anything else the team wants to include for the design judges

The Design Document must be printed or written; no electronic copies will be accepted or printed out the day of the event. These documents will not be returned.

(Sample judging score sheet)


The competition is a time trial followed by an 8-car double elimination.  The racetrack is 20 meters long and set up on a hard, flat, smooth surface such as a tennis court and a non-slick vinyl surface is used for the track lanes.

Time Trials:

During the time trial phase of the race, teams have the opportunity to attempt to have their vehicle drive down the track (a run) up to three times.  After each run, the vehicle’s time will be recorded.  A ‘DNF’ or ‘Did Not Finish’ will be recorded for vehicles that lose their salt canister, drive off the track, cross into another lane, do not cross the finish line, or are otherwise disqualified.

Time trials will be offered every 30 seconds for a given period of time. It is a team’s responsibility to line up and run their vehicle (up to three times) within the time allotted.  Any teams in line when the end of the time trial event is called by the judges will not be allowed to run.  When ‘Go’ is called, vehicles that do not start moving before the other vehicle reaches the finish will be given a DNF and must be removed from the track immediately.  If neither vehicle moves, the teams will be given 20 seconds after ‘Go’ is called before DNF’s are given to both vehicles.  Vehicles are then to be promptly removed.

The eight teams with the fasted individual run times will move to the head-to-head competition.

Head-to-Head Competition:

The head-to-head competition is an eight-team, double elimination event.  This means that a team must lose twice before being eliminated from the competition.  Teams will race against other teams to determine the first, second, and third place winners.


Competition Rules

  1. The B.A.T. Mobile Challenge ‘kit’ (as distributed by FSEC) contains a lithium ion battery, motor, wiring harness, battery connector, battery recharger, and an A/C adapter. No other batteries motors or wiring harnesses may be used in the competition.  Students must use the unaltered battery, wire harness and motor as the only method of powering the car. Motors may not be re-wound or disassembled.  Only one battery and one motor is allowed per car.  The rest of the car design and components will be up to the creativity and ingenuity of the students. All cars must be designed and built only by the students with limited assistance from the coach, parents, mentors or other non-team student members. 

  2. The vehicle cannot exceed the following dimensions: 20 cm wide, 40 cm in length, and 20 cm in height.  A 3 x 3 cm space must be left for the assigned car number (provided by the Florida Solar Energy Center at event check-in) to be applied and visible from the side, top or front of the body of the car. 

  3. The vehicle must be designed with a compartment to carry a payload of 1 full salt box (i.e. Morton salt 26oz).  The salt box may not be part of the vehicle’s structure.  Velcro, tape, or any other adhesive cannot be used to secure the container, however you may use zip ties, rubber bands or string to hold the container on the chassis.  The salt box will be supplied at check-in the day of the event, and must remain unaltered.  The container can either stand up or lay on its side, however it must remain in the vehicle for the entire race.  If the container falls from the vehicle during the race, this will result in a Did Not Finish (DNF).

  4. The lithium ion battery can only be recharged with the battery charger provided in the car kit.  Electricity to plug in the battery rechargers will be available the day of the event. However teams are encouraged to arrive race day with a full charge.

  5. A guide wire attachment, referred to as an eyelet, must be attached to the car.  Examples of possible designs are shown below.  

    Drawing of a square and a round eyelet.

    A 1/16" stainless steel guide wire will be no more than 1.5 cm from the surface of the track.  This guide wire will go through the attached eyelet on the car, serving as the steering mechanism, and keeping the car in its lane.  The vehicle must be easily removed from the guide wire without disconnecting the guide wire.  This is the only allowable method of steering the car. No radio control is permitted in the cars.  The eyelet must be used for steering only and must be directly hooked onto the guide wire.  Any guide wire attachment or eyelet used should not support the vehicle (such as a grooved spool located on top of the car guiding the car down the track). All wheels must be in contact with the track. The guide wire must be attached to the car throughout the course of the race.  If the car disengages from the guide wire, this will result in a DNF. 

  6. An on/off switch must be present on the vehicle. This switch may be of any design.

  7. At race time, the vehicle will be placed behind the starting line and all wheels must be in contact with the ground. An early start or push start will result in a DNF. One team member must wait at the finish line to catch the vehicle upon completion.  Team members may not accompany or touch the vehicle after the start has been called. Vehicles stalled on the track may be retrieved after the end of the race has been declared by the judges. Students must not walk on the track. Any car that does not finish in 20 seconds will be considered DNF.

  8. Repairs may be made to vehicles as necessary between heats. However, no extra time will be given for repairs, and the race will not be paused for repairs to be completed.

  9. Judges may inspect cars at any time before, during or after heats.

Modified 11/14/2013