里程计校准行为树

该行为树通过 DriveOnHeading 和 Spin 行为，驱动机器人按逆时针（CCW）方向沿正方形路径行驶三圈。机器人以 0.2 m/s 的速度沿每条边行驶 2 米，然后原地旋转 90 度。该行为树是测量里程计精度的基础实验，可重复执行，用于调整里程计相关参数以提高定位精度。

  <root main_tree_to_execute="MainTree">
    <BehaviorTree ID="MainTree">
      <Repeat num_cycles="3">
        <Sequence name="Drive in a square">
          <DriveOnHeading dist_to_travel="2.0" speed="0.2" time_allowance="12"/>
          <Spin spin_dist="1.570796" is_recovery="false"/>
          <DriveOnHeading dist_to_travel="2.0" speed="0.2" time_allowance="12"/>
          <Spin spin_dist="1.570796" is_recovery="false"/>
          <DriveOnHeading dist_to_travel="2.0" speed="0.2" time_allowance="12"/>
          <Spin spin_dist="1.570796" is_recovery="false"/>
          <DriveOnHeading dist_to_travel="2.0" speed="0.2" time_allowance="12"/>
          <Spin spin_dist="1.570796" is_recovery="false"/>
        </Sequence>
      </Repeat>
    </BehaviorTree>
  </root>