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AS (Autonomous System) State Machine

Reference: FS Rules 2026 v1.1, Section T14.8, Figure 15 (page 68)

States

State ASSI Color Description
AS Off off System inactive, no autonomous capability
AS Ready yellow continuous Mission selected, all checks passed, brakes engaged, waiting for RES Go
AS Driving yellow flashing (2-5 Hz) Vehicle is in R2D, autonomous driving active
AS Finished blue continuous Mission completed, vehicle at standstill
AS Emergency blue flashing (2-5 Hz) EBS activated, emergency state

State Determination (Figure 15 - Continuous Decision Tree)

The AS status is continuously evaluated based on current conditions, not discrete event-driven transitions:

Entry → EBS activated?
├─ YES → Mission finished AND Vehicle at Standstill?
│  ├─ YES → SDC open at RES?
│  │  ├─ YES → AS Emergency
│  │  └─ NO  → AS Finished
│  └─ NO  → AS Emergency
└─ NO  → Mission Selected AND ASMS On AND ASB checks OK AND TS Active?
   ├─ NO  → AS Off
   └─ YES → R2D (Ready-to-Drive)?
      ├─ YES → AS Driving
      └─ NO  → Brakes engaged?
         ├─ YES → AS Ready
         └─ NO  → AS Off

Key Timing Requirements

  • T14.8.4: R2D mode may only be entered by the RES "Go" signal, after the system has remained in "AS Ready" for at least 5 seconds
  • T14.8.5: The vehicle must not start moving until the system has remained in "AS Driving" for at least 3 seconds

Conditions for Each State

AS Off

  • EBS not activated AND (no mission selected OR ASMS off OR ASB checks failed OR TS not active OR brakes not engaged)

AS Ready

  • EBS not activated AND mission selected AND ASMS on AND ASB checks OK AND TS active AND brakes engaged AND NOT in R2D

AS Driving

  • EBS not activated AND all AS Ready conditions met AND R2D active (via RES Go after 5s in AS Ready)

AS Finished

  • EBS activated AND mission finished AND vehicle at standstill AND SDC NOT open at RES

AS Emergency

  • EBS activated AND (vehicle not at standstill OR mission not finished OR SDC open at RES)

Required Missions (T14.10)

  • Acceleration
  • Skidpad
  • Autocross (DC only)
  • Trackdrive (DC only)
  • EBS Test
  • Inspection
  • Manual Driving

Hardware Interfaces

  • RES (Remote Emergency System): Physical remote with Go button and emergency stop (T14.3)
  • ASMS (Autonomous System Master Switch): Physical rotary switch, must have lockout/tagout (T14.5)
  • ASSI (Autonomous System Status Indicator): 3x lights showing AS state (T14.9)
  • AMI (Autonomous Mission Indicator): Displays selected mission, readable from outside (T14.10)
  • ASB (Autonomous System Brake): Emergency braking with EBS (T15)

Our Implementation Notes

Our kart (APC entry) doesn't have all the ADS-DV hardware (no physical RES, no ASMS switch). We simulate these via dashboard buttons. The state machine in state_machine_node.py maps:

  • Dashboard "start" button → RES "Go" signal
  • Dashboard "stop" button → equivalent to ASMS off (returns to AS Off)
  • Dashboard "ebs" button → EBS activation (AS Emergency)
  • Dashboard mission selector → mission selection + simulated ASMS on

The 5s AS_READY wait and 3s AS_DRIVING delay are NOT currently implemented but are required for competition compliance.