{
  "msg": "fourbar unified simulate PRRR",
  "req_code": "CASE_FB_UNIFIED_PRRR",
  "req_from": "wasm_test",
  "req_cmd": "Cmd_FourBar_Simulate",
  "req_param": {
    "mechanismType": "PRRR",
    "L_AB": 0.5,
    "L_BS": 2.0,
    "S_OFS": 0.0,
    "startSliderX": 1.5,
    "endSliderX": 2.5,
    "duration": 1.0,
    "stepTime": 0.25
  }
}