sequenceDiagram
    actor Op as Operator
    participant Prep as Sample Prep
    participant Plan as Excel Test Plan
    participant SW as Control Software
    participant TR as RAPID Tribometer

    Op->>Prep: Request test
    Op->>Prep: Get samples
    Op->>Prep: Load samples onto plates
    Op->>Prep: Load ball holders (3 counterfaces per holder)
    Op->>Plan: Create test plan<br/>(Sample Plate, Plate Location, Sample ID, Save Location,<br/>Folder Name, X/Y/Z Offset, Load, Iterations)
    Op->>TR: Transfer plates to tribometer
    Op->>TR: Set up platter
    Op->>SW: Activate software
    Op->>SW: Load plan
    SW->>TR: Activate tribometer
    TR-->>SW: Run reciprocating tests (execution loop, see D5)
    Op->>SW: Software stop
    SW-->>Op: Save avg files
    Op->>TR: Remove plates and platters
    Op->>SW: Close software
    Op->>TR: Pull equipment out
