ParkingRobot/docs/superpowers/specs/2026-08-05-movementtest-longitudinal-time-step-design.md

MovementTest Longitudinal Time-Step Design

Goal

Reduce the observation-test longitudinal QP size without relaxing the solver accuracy, time budget, vehicle limits, or observe-only behavior.

Decision

Add configurable TimeHorizonSeconds and OutputTimeStepSeconds values to the trajectory-observation MovementTest, with defaults of 6d and 0.10d seconds.

TimeHorizonSeconds controls how far into the future the ST plan covers. OutputTimeStepSeconds controls how many knots divide that horizon and must not exceed it. At the parking-test speed limit of 0.20m/s, a 0.10-second knot interval corresponds to at most 0.02m of travel between knots.

Scope

• Add, snapshot, and validate TimeHorizonSeconds and OutputTimeStepSeconds in TrajectoryObservationSettings.
• Expose both settings in the MovementTest as public fields with defaults of 6d and 0.10d.
• Copy both values to the session-local EmPlannerConfiguration.Scheduling configuration.
• Verify custom settings reach the planning request and non-positive values are rejected.
• Add Chinese XML documentation comments to the MovementTest fields and settings properties, explaining horizon coverage, timestamp spacing, defaults, and the distinction from ObserverPeriodSeconds.

Non-goals

• Keep ObserverPeriodSeconds = 0.05d.
• Keep SolverTimeoutSeconds = 0.50d, MaximumOsqpIterations = 12000, and all 1e-5d solver tolerances.
• Do not change production EM defaults, maps, vehicle constraints, or command output behavior.