Autonomous Challenge @ CES: Passing Competition Rules
This competition will be conducted as a single elimination tournament consisting of multiple rounds of head-to-head matches culminating in a championship match. Two cars will participate in each passing competition match. The two cars will take turns playing the role of leader (defender) and passer/follower (attacker), and passes will be attempted at ever increasing speeds until one or both cars is unable to successfully complete a pass.
Competition Bracket:
The competition will be conducted as a single elimination tournament. Six teams qualified for the competition in two groups. The first group (group A) consists of four teams and the second group (group B) consists of two teams. There will be three rounds in the competition. The two top seeded teams from group A will receive a bye in the first round. The bottom two seeds will compete in the first round (each against a group B team).
The winner of the championship round will be the overall winner of the tournament/competition. The loser of the championship round will be the second place team for the competition.
Qualification and Seeding:
Six teams have been qualified for the passing competition. The four teams that qualified first (group A) will participate in a time trial competition to determine their seeding in the bracket.
Match Execution:
The top-seeded team (the team with the best qualifying time) will start as the attacker. The bottom-seeded team will start as the defender. If the match ends in a tie, the top-seeded team will advance. A match will progress in the following order:
Speed Level Stair Step:
A single head to head match will consist of multiple rounds
A single speed level for the defenders will be set for each round
In every round each car will be given a passing attempt (see description of an attempt below) at the speed target for the round
If both cars successfully complete a pass during the round, a new round with a new speed will begin
If only one car is able to successfully complete a pass during a round, they will be the winner of the match
If neither car is able to successfully complete a pass during a round, the match will end in a tie.
If the first attacker in a round fails to complete a pass, a reordering operation to reverse the roles will be carried out
A progression of speed levels will be decided before each match. A speed level progression might look like the following (in mph): 80, 100, 115, 125, 130, 135, 140, 145, 150...
Passing Zones:
For speed levels up to a high speed cutoff (less than 130 mph), passes can only be carried out in the predefined passing zone (shown in Figure 1). A pass must be initiated and completed within the passing zone. The approximate location of the passing zone start is currently 36.274474°, -115.005893°. The approximate location of the passing zone end is currently 36.268946°, -115.011608°.
For nominal speeds greater than or equal to the high speed cutoff (130 mph), the passing zone will be extended to a full lap. The start of the passing zone will remain in the same location for all passing attempts.
Figure 1: Approximate location of the low speed passing zone at LVMS shown in red. The high speed passing zone will extend to a full lap, but it will still start in the same location as the low speed passing zone
Passing Attempts:
Each attacker will have one opportunity (one full traversal of the passing zone) per speed level to complete a pass. Each passing attempt will begin between turn three and four (at a precise location to be determined later) and will be signaled by a “waving green flag” issued by scoring prior to entering the passing zone. The passing attempt will end after a successful pass or a failed pass when either car exits the passing zone before a successful pass is completed.
Initiation of a Pass:
A pass will be considered to be initiated when the attacker has closed the gap with the defender to less than 2 meters and is on a non-intersecting race line. A pass can only be initiated within the passing zone.
Completion of a Pass:
For a pass to be considered successfully completed, the attacker must overtake the defender, open a 30 meter longitudinal gap, and then “close the door” by switching to the inner lane. The pass will be considered complete as soon as the attacker fully crosses the centerline. After closing the door, the attacker should maintain a speed greater than or equal to the speed level for the round until the roles are reversed. The pass must be completed entirely in the passing zone. Note that at or above the nominal high speed cutoff (130 mph), the passing zone will extend to one full lap.
Formation Laps:
Except for the start of the race, the initial warm-up and passing runs at or above the high speed cutoff, there will be no dedicated formation laps during a match. After a pass is completed, and the roles are reversed, the new attacker is expected to close the gap with the new defender before reaching the passing zone again.
If the previous attacker opened an unusually large gap during its passing attempt, a full formation lap may be granted to the new attacker at the discretion of the race director. In such a case, the waving green flag would be withheld until the formation lap is complete and the cars approach the passing zone again.
Similarly, if a passing attempt is unsuccessful but a role reversal is still required to decide the match, one or more formation laps may be used to reconfigure the cars. The necessary flag sequence for the reconfiguration will be determined by scoring, but may include a yellow and/or red flag to the new defender to slow its speed and give the new attacker a chance to close the gap quickly. Conversely, if deemed safe based on the configuration of the cars – such as if the previous attacker is even or ahead of the previous defender – the previous defender may be sent a yellow and/or red flag to allow the previous attacker to move ahead and create a gap before switching roles and starting one or more formation laps.
For speeds at or above the high speed cutoff, a full formation lap will be automatically granted after each successful pass unless it is unnecessary.
Flag Logic:
The passing-specific flags should be interpreted as follows:
Track condition flags:
Green flag: No passing allowed. Also, the green flag has additional specific meanings depending on the associated vehicle signal flag:
Vehicle signal flag is Null (0) or No active flag (1): Green (or yellow) flag indicates that the car is on a warm up lap
Vehicle signal flag is Defender (5): Green flag indicates that the car should move to the inside lane and set its speed to the constant speed level for the round.
Vehicle signal flag is Attacker (7): Green flag indicates that the car should close the gap with the defender
Waving Green flag (start the passing attempt): The attacker may initiate a pass upon entering the next passing zone. This flag indicates the passing is now allowed, but the passing still must only occur within the passing zone.
Vehicle signal flags:
Defender (5): The car should move to and stay on the inside lane and maintain the nominal speed level for the round.
Attacker (7): The car should close the gap (under green) and attempt a pass in the passing zone (under waving green). The attacker is primarily responsible for maintaining the safety distance with the defender.
Safety Distances:
The attacker must maintain a safety distance of at least 2 meters laterally and 30 meters longitudinally (when on an intersecting line) to the defender at all times. Violations, particularly those that are clearly unsafe, may lead to an immediate end of a match and disqualification of the offending car at the discretion of the race director.
Speed Limits:
Yellow Flag: Maintain speed between 60 - 80 mph except in pit lane
Black Flag: No limit until entering pit lane
Pit Lane: Speed limit is 60 mph except in the “slow zone” for which the speed limit is 30 mph, and consists of the section of the pit lane next to the active pit boxes as well as an approach buffer. The slow zone/approach buffer starts at lat/lon 36.275328°, -115.009474°, and the slow zone ends at lat/lon 36.273957°, -115.012076°.
Defender Obligations:
The defender must stay on the inner half of the track, meaning that no part of the car may touch or cross the centerline of the track within that zone. If the new defender is not already on the inner half of the track when the roles are reversed, it must start moving to the inner lane immediately. The defender must also maintain its speed within +/- 5% of the target in the passing zone.
Attacker Obligations:
Under a green flag, the attacker must close the gap with the defender, but not pass or close the gap to less than 2 meters (non-intersecting line) or 30 m (intersecting line). Under a waving green flag, the attacker must wait to pass the defender until after crossing the start line of the passing zone.
Crashes:
Prior to the Championship round:
In the event that a crash occurs that disables both cars, the Race Director may decide to advance a previously eliminated car, or determine an alternate outcome based on the circumstances.
If only one car is disabled in a crash, the other car will immediately advance, unless it was determined by the race director to be at fault in the crash and subsequently disqualified, at which point an alternate car would be chosen to advance as described above.
During the Championship round: In the event that a crash occurs that disables one or both of the cars the Race Director will determine the winner according to the circumstances
Judging Adherence to the Rules:
The race director and race stewards (as relevant) will determine whether any violations of the rules have occurred and will assess an appropriate penalty.
Passing Competition run sequence:
The two teams competing in a passing competition match will prepare their race cars to fire their engines
When the race starts, Scoring will issue an orange flag to fire both engines, and the teams will confirm to Scoring that the engines have fired.
Match Run Start:
Scoring sends a yellow flag to the lead car, which will autonomously exit the pit box and proceed to the track
When the lead vehicle is safely ahead, scoring will send a yellow flag to the second vehicle, which will also autonomously exit the pit box and proceed to the track
Once both cars are on the track, Scoring will send a green flag to both cars starting warmup and formation laps
The cars will receive at least 3 warm up laps under green before receiving attacker/defender roles. The speeds for the warm up laps should remain between 60 - 80 mph. The teams can adjust the speeds manually as necessary during the warmup laps to keep a safe gap.
At the end of the warm up laps, the cars will be assigned their roles via vehicle signal flags from scoring at which point the defender should set its speed to 80 mph (speed for the first round, and move to the inner lane, and the attacker should begin closing the gap.
Match Execution:
After completing the initial formation laps a waving green flag will be sent to both cars to indicate the start of the first passing attempt
After a successful passing attempt a role reversal will be triggered by scoring , and the appropriate vehicle signal flags (attacker and defender) will be sent to the cars.
After an unsuccessful passing attempt, where a role reversal is still required, scoring will send a sequence of flags to choreograph the reconfiguration.
A waving green flag will be sent to trigger the start of the next attempt
This process will continue until the match is complete
Team Interaction with the Vehicle and Scoring:
The teams will view telemetry from their race car (via CURWB network) in their pits during the entire run
Some telemetry for the other vehicle in the match will be available via the MyLaps interface
Lap distance for all cars will be provided to all cars via MyLaps. This will provide coarse location information that can be used by the attacker to locate the defender when outside of sensor range and to automatically close the gap (note that resolution or accuracy of this data may be reduced)
During the runs the teams will be allowed to set and adjust the target velocity (speed limit) on their vehicles via their base station. When serving as the lead vehicle the target velocity will be set to a constant value and the car must maintain that speed to within +/- 5%.
When attempting to overtake the lead vehicle, the team may adjust the target speed / speed limit arbitrarily, but should not change other parameters or send other commands to the vehicle.
If a car fails to overtake the lead vehicle and a reordering of the cars is required, additional interaction by the teams may be allowed
Match Completion:
When the match is complete, scoring will issue appropriate flags (yellow, black and red) as needed to automatically bring the cars to the pit.
AC @ CES Time Trial Seeding Event
The Time Trial Seeding Event will be carried out immediately prior to the passing competition. The four top qualifying teams will participate.
Overview:
One race car will compete on the track at a time
Run order will be determined by a blind draw
Each race car will receive a maximum of 10 full laps (preceded by an “out lap” and succeeded by an “in lap”) for their attempt.
The score for the time trial will be the highest lap speed on any of the completed laps
Contingencies:
If a team is unable to launch their car from the pits during their allotted time, they may be granted an additional attempt at the discretion of the Race Director.
If a team fails to complete a lap during the time trial, they will be seeded last
If more than one team fails to complete a lap during the time trial, they will be seeded according to their run order from the blind draw (first in the order receives the best seed).
Speed Limits:
Speed limits are as follows, and apply to both the passing competition and the time trial seeding event:
Yellow Flag: 80 mph
Black Flag: No limit until entering pit lane
Pit Lane: Speed limit is 60 mph except in the “slow zone” for which the speed limit is 30 mph, and consists of the section of the pit lane next to the active pit boxes as well as an approach buffer. The slow zone/approach buffer starts at lat/lon 36.275328°, -115.009474°, and the slow zone ends at lat/lon 36.273957°, -115.012076°.
Pit Slow Zone (30 mph) Start ( 36.275328°, -115.009474°) and end ( 36.273957°, -115.012076°)
Team Interaction with the Vehicle and Scoring:
Teams are permitted to manually adjust the target speeds of their cars during their run.
Autonomous Challenge @ CES: Passing Competition Speed Tiers
For the green speeds the passing must be completed within the short passing zone. The yellow ones must be completed within one lap.
