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The robot rotates when he is near the goal

Hello

I'm using Ubuntu 12.04 and ROS fuerte

I have my custom robot and now I'm reaching navigation stack.

When I send a goal. the global path planner works fine. But when the robot is near to the goal, it always rotate and never reach the goal.

I think I need to tune the parameters but I couldn't reach to the correct combination.

Here is the parameters of the baselocalplanner:

TrajectoryPlannerROS:
  max_vel_x: 0.5
  min_vel_x: -0.5
  max_rotational_vel: 1.0
  min_rotational_vel: 1.0
  min_in_place_rotational_vel: 1.0

  acc_lim_th: 3.2
  acc_lim_x: 2.5
  acc_lim_y: 2.5

  holonomic_robot: false

Any idea?

Asked by nouf on 2015-05-03 10:23:47 UTC

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Answers

Do you have these set;

  # Goal tolerance parameters in meters (lower means closer and harder/slower to achieve)
  # Check: stay outside footprint
  yaw_goal_tolerance: 0.3
  xy_goal_tolerance:  0.4
  latch_xy_goal_tolerance: false  # do not rotate on finding goal

  # Forward Simulation 
  # Check: minimum velocity multiplied by the sim_period is less than twice the tolerance on a goal. 
  sim_time: 10.0                   # The amount of time to forward-simulate trajectories in seconds
  sim_granularity: 0.1             # The step size, in meters, to take between points on a given trajectory
  angular_sim_granularity: 0.2     # The step size, in radians, to take between angular samples on a given trajectory.
  vx_samples: 10                   # The number of samples to use when exploring the x velocity space
  vtheta_samples: 10               # The number of samples to use when exploring the theta velocity space


  # Trajectory Scoring Parameters
  path_distance_bias: .3           # The weighting for how much the controller should stay close to the path it was given
  goal_distance_bias: .3           # The weighting for how much the controller should attempt to reach its local goal,controls speed
  occdist_scale:          1
  forward_point_distance: 1
  meter_scoring:        true    # If true, distances are expressed in meters; otherwise grid cells
  publish_cost_grid:    true 
  prune_plan:           false

Asked by rnunziata on 2015-05-03 11:12:43 UTC

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When I used them, it rotates endlessly

Asked by nouf on 2015-05-03 11:54:38 UTC

Check this one it might help you http://answers.ros.org/question/9795/tuning-navigation-robot-keeps-rotating-when-close-to-its-goal/

Asked by dimkirt on 2015-06-09 13:03:28 UTC

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Does it stop rotating if you set yaw_goal_tolerance to 10?

Asked by David Lu on 2015-06-09 19:42:23 UTC

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