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+# MovementTest ST Time Controls Implementation Plan
+
+> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox syntax for tracking.
+
+**Goal:** Expose configurable ST horizon and trajectory timestamp spacing for observation-only MovementTest sessions.
+
+**Architecture:** TrajectoryObservationSettings owns TimeHorizonSeconds and OutputTimeStepSeconds, preserves them in a validated snapshot, and enforces a time step no larger than the horizon. Public MovementTest fields feed those settings, then TrajectoryObservationController copies both values into its session-local EM schedule.
+
+**Tech Stack:** C# 10, .NET, EMPlannerVerificationHost.
+
+## Global Constraints
+
+- TimeHorizonSeconds defaults to 6d.
+- OutputTimeStepSeconds defaults to 0.10d.
+- OutputTimeStepSeconds must be positive and no greater than TimeHorizonSeconds.
+- ObserverPeriodSeconds stays 0.05d.
+- SolverTimeoutSeconds stays 0.50d, MaximumOsqpIterations stays 12000, and all solver tolerances stay 1e-5d.
+- Do not change production EM defaults, vehicle/map constraints, or observe-only command behavior.
+
+---
+
+### Task 1: Propagate ST time controls into an EM request
+
+**Files:**
+
+- Modify: ClumsyPilot/tests/EMPlannerVerificationHost/TrajectoryObservationChecks.cs
+- Modify: ClumsyPilot/ParkrobTrajplanner/tarjplanner_movementtest/TrajectoryObservationContracts.cs
+- Modify: ClumsyPilot/ParkrobTrajplanner/tarjplanner_movementtest/MovementTest.TrajectoryObservationTest.cs
+- Modify: ClumsyPilot/ParkrobTrajplanner/tarjplanner_movementtest/TrajectoryObservationPipeline.cs
+
+**Interfaces:**
+
+- Consumes: TrajectoryObservationSettings.CreateValidatedSnapshot() and TrajectoryObservationController.StartCycle(...).
+- Produces: TimeHorizonSeconds and OutputTimeStepSeconds in EmPlanningRequest.Configuration.Scheduling.
+
+- [ ] **Step 1: Write the failing test**
+
+Add assertions for the visible defaults and request propagation:
+
+~~~csharp
+Verification.True(source.Contains("public double TimeHorizonSeconds = 6d;"),
+    "observer MovementTest exposes the ST time-horizon default");
+Verification.True(source.Contains("public double OutputTimeStepSeconds = 0.10d;"),
+    "observer MovementTest exposes the ST timestamp-spacing default");
+
+var settings = new TrajectoryObservationSettings
+{
+    TimeHorizonSeconds = 4d,
+    OutputTimeStepSeconds = 0.20d,
+};
+// Start one controller cycle.
+Verification.NearlyEqual(4d, request.Configuration.Scheduling.TimeHorizonSeconds,
+    "observer configured ST time horizon");
+Verification.NearlyEqual(0.20d, request.Configuration.Scheduling.OutputTimeStepSeconds,
+    "observer configured ST timestamp spacing");
+~~~
+
+Assert zero horizon, zero step, and a step larger than the horizon are rejected.
+
+- [ ] **Step 2: Run focused verification to verify it fails**
+
+Run:
+
+~~~powershell
+dotnet run --project ClumsyPilot/tests/EMPlannerVerificationHost/EMPlannerVerificationHost.csproj -- trajectory-observation
+~~~
+
+Expected: FAIL because the ST time-control properties are absent.
+
+- [ ] **Step 3: Write the minimal implementation**
+
+Add public settings and comments:
+
+~~~csharp
+/// <summary>单次 ST 轨迹覆盖的未来时长，单位 s；不等于观察循环周期。</summary>
+public double TimeHorizonSeconds { get; set; } = 6d;
+
+/// <summary>发布 Trajectory 相邻 TimeFromStart 时间戳的间隔，单位 s；不等于观察循环周期。</summary>
+public double OutputTimeStepSeconds { get; set; } = 0.10d;
+~~~
+
+Validate both values and require OutputTimeStepSeconds to be no larger than TimeHorizonSeconds. Copy them through the MovementTest and use:
+
+~~~csharp
+configuration.Scheduling.TimeHorizonSeconds = settings.TimeHorizonSeconds;
+configuration.Scheduling.OutputTimeStepSeconds = settings.OutputTimeStepSeconds;
+~~~
+
+- [ ] **Step 4: Run focused verification to verify it passes**
+
+Run:
+
+~~~powershell
+dotnet run --project ClumsyPilot/tests/EMPlannerVerificationHost/EMPlannerVerificationHost.csproj -- trajectory-observation
+~~~
+
+Expected: PASS trajectory-observation.
+
+- [ ] **Step 5: Run full regression and build**
+
+Run:
+
+~~~powershell
+dotnet run --project ClumsyPilot/tests/EMPlannerVerificationHost/EMPlannerVerificationHost.csproj -- em-all
+dotnet build ClumsyPilot/ClumsyPilot.csproj --no-restore
+~~~
+
+Expected: all suites pass and the build reports zero errors.
+
+- [ ] **Step 6: Commit implementation**
+
+~~~powershell
+git add ClumsyPilot/tests/EMPlannerVerificationHost/TrajectoryObservationChecks.cs ClumsyPilot/ParkrobTrajplanner/tarjplanner_movementtest/TrajectoryObservationContracts.cs ClumsyPilot/ParkrobTrajplanner/tarjplanner_movementtest/MovementTest.TrajectoryObservationTest.cs ClumsyPilot/ParkrobTrajplanner/tarjplanner_movementtest/TrajectoryObservationPipeline.cs
+git commit -m "feat: configure MovementTest ST time controls"
+~~~
+