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[daohu527]

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首先感谢文档的帮助，在此补充我的经历。

如何创建停车位以及使用valet_parking场景

背景：我使用RoadRunner绘制地图，其中绘制了停车位(parking space)，但是导出的xml文件并不可以直接使用
原因：Apollo中需要指明lane与parking space之间的逻辑关系，即overlap
解决方法：增加相关信息

原始xml中仅有停车位的几何信息

停车位30和28

<object type="parkingSpace" id="30" heading="-1.0303750580989222e+00">
<outline>
<cornerGlobal x="1.1049792936570825e+02" y="4.1670647536073616e+01" z="0.0000000000000000e+00"/>
<cornerGlobal x="1.1049789634233366e+02" y="4.1670632680485234e+01" z="0.0000000000000000e+00"/>
<cornerGlobal x="1.1049793958777217e+02" y="4.1670578636280730e+01" z="0.0000000000000000e+00"/>
<cornerGlobal x="1.1049797261112907e+02" y="4.1670593491856835e+01" z="0.0000000000000000e+00"/>
</outline>
</object>
<object type="parkingSpace" id="28" heading="5.3465927741245156e-01">
<outline>
<cornerGlobal x="1.1049817185303753e+02" y="4.1670637364854123e+01" z="-1.1102230246251565e-16"/>
<cornerGlobal x="1.1049819190569502e+02" y="4.1670611974220712e+01" z="-1.1102230246251565e-16"/>
<cornerGlobal x="1.1049826423303819e+02" y="4.1670644086971350e+01" z="-1.1102230246251565e-16"/>
<cornerGlobal x="1.1049824418039917e+02" y="4.1670669477617238e+01" z="-1.1102230246251565e-16"/>
</outline>
</object>

xml中增加overlap

lane与parking space之间的逻辑关系，是指通过哪一条lane能够停入相应的停车位，比如，在lane(2_0_-1)旁边有个paking space(30)。

<lane id="-1" uid="2_0_-1" type="driving" turnType="noTurn" direction="forward">
<link>
<predecessor id="11_0_-1"/>
<successor id="5_0_-1"/>
<neighbor side="left" id="2_0_1" direction="opposite"/>
<neighbor side="right" id="2_0_-2" direction="same"/>
</link>
<centerLine>
<geometry sOffset="0.0000000000000000e+00" x="1.1049783753955374e+02" y="4.1670880619625869e+01" z="4.4066143035888672e-01" length="1.4379555194880160e+02">
<pointSet>
...
</pointSet>
</geometry>
</centerLine>
<objectOverlapGroup>
<objectReference id="30" startOffset="0" endOffset="1.4379555194880160e+02"/>
</objectOverlapGroup>

先找到lane id，在xml中是uid。在其中补充objectOverlapGroup，如下。

<objectOverlapGroup>
<objectReference id="30" startOffset="0" endOffset="1.4379555194880160e+02"/>
</objectOverlapGroup>

startOffset与endOffset本应是这个停车位在lane中的位置。但是在apollo_9.0/modules/map/pnc_map/path.cc中的GetAllOverlaps函数中有一句

if (lane_overlap_info.start_s() <= lane_segment.end_s && lane_overlap_info.end_s() >= lane_segment.start_s)

建议将startOffset设置为0，endOffset设置为lane的长度。

base_map中增加overlap

如果是使用xml再转换成base_map，以上步骤即可。若是直接修改base_map.txt，步骤稍多一点。
1.先创建overlap

overlap {
  id {
    id: "overlap_8"
  }
  object {
    id {
      id: "2_0_-2"
    }
    lane_overlap_info {
      start_s: 0
      end_s: 143.7955519488016
      is_merge: false
    }
  }
  object {
    id {
      id: "30"
    }
    parking_space_overlap_info {
    }
  }
}

2.在parking space中增加overlap

parking_space {
  id {
    id: "30"
  }
  polygon {
    point {
      x: 458205.92057472188
      y: 4613331.3964851508
      z: 0
    }
    point {
      x: 458203.16197796242
      y: 4613329.7631899416
      z: 0
    }
    point {
      x: 458206.72693157109
      y: 4613323.7420681585
      z: 0
    }
    point {
      x: 458209.48552830983
      y: 4613325.3753633806
      z: 0
    }
  }
  overlap_id {
    id: "overlap_8"
  }
  heading: -1.0303750580989222
}

3.在lane(2_0_-1)中增加overlap

length: 143.79511082341818
  speed_limit: 4.3462461330410509
  overlap_id {
    id: "overlap_8"
  }
  successor_id {
    id: "5_0_-2"
  }
  left_neighbor_forward_lane_id {
    id: "2_0_-1"
  }

在Apollo9.0中，验证了以上内容，无论是垂直泊车还是平行泊车均可成功。
补充一点，官方地图中没有平行停车位，使用自制地图测试平行泊车时，发现hybrid_a_star无法规划出一条路径，排查原因是end_pose不合理。
解决方法：
在modules/planning/tasks/open_space_roi_decider/open_space_roi_decider.cc中的SetParkingSpotEndPose函数中，修改end pose的计算方法。

Vec2d middle_right = (right_top + right_down) / 2.0;
    end_pt = middle_right +
             Vec2d::CreateUnitVec2d(parking_heading) * (-vehicle_params_.front_edge_to_center() - parking_depth_buffer);