Shell Eco-Marathon Simulation

Version 6 represents a major correction in the simulation philosophy. Earlier versions used PID control to regulate vehicle speed, which produced smooth cruise-control behavior. While stable, this did not represent the real Shell Eco-Marathon driving strategy.

Real competition vehicles operate using a burn-and-coast strategy, where the engine runs at high efficiency during short bursts followed by long coasting periods with zero fuel consumption. Version 6 removes the PID controller and replaces it with a pure threshold-based control system that produces realistic pulsed throttle behavior.

Velocity Behavior Comparison

Earlier PID-controlled simulations produced nearly constant velocity. The burn-coast controller produces oscillating velocity between upper and lower thresholds, matching real competition driving.

PID Controller Velocity Response (V3–V5) — nearly constant speed

Burn-Coast Velocity Response (V6) — realistic oscillating speed profile

Throttle Behavior Comparison

Throttle behavior clearly shows the difference between the two control approaches. The PID controller continuously adjusts throttle; the burn-coast controller produces discrete full-power pulses followed by long coasting intervals.

PID Throttle Response — continuous modulation

Burn-Coast Throttle Response — full on/off pulses

Subsystem Architecture Updates

Driver Strategy Redesign

Previous Strategy (V3–V5)

PID controller regulated speed continuously with smooth throttle response
Near-constant velocity — behaved like automotive cruise control
Unrealistic for Shell Eco-Marathon competition

Burn-Coast Strategy (V6)

PID controller removed — throttle is fully on or fully off
Velocity thresholds control switching with hysteresis to prevent rapid chattering
Realistic pulsed engine operation matching competition driving technique

Control Logic
If velocity < v_low → Throttle = 1 | If velocity > v_high → Throttle = 0 | Otherwise hold previous state

Simulation Behavior

Throttle becomes square-wave pulses; velocity forms repeating triangular patterns
Engine operates near peak efficiency with long coasting intervals to minimize fuel use
Vehicle completes full track distance

Simulation Gallery

Improvements Over V5

Realistic driver behavior matching Shell Eco-Marathon competition strategy
Stable hysteresis switching with improved physical realism
Reduced modeling assumptions

Shell Eco-Marathon Vehicle Simulation — V6

Overview