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Hi everyone,

I am using the navigation stack on my own wheeled robot. at first i used a converter to convert 220 v to 14.7 v to run my robot. using this power my robot navigated nicely in the environment. Then i equipped my robot with a 25 v LiPo battery and now when navigating, it hits the obstacles much and when i command it to go to a far distance goal, turn around much. my navigation config is as follow. what should i do? I appreciate any help.


max_vel_x: 2.5
min_vel_x: 0.5
max_vel_theta: 13.736
min_vel_theta: -13.736
min_in_place_rotational_vel: 2
escape_vel: -0.5
acc_lim_theta: 3.12
acc_lim_x: 0.568
acc_lim_y: 0.568
xy_goal_tolerance: 0.5
yaw_goal_tolerance: 3
holonomic_robot: false


obstacle_range: 2.5
raytrace_range: 3.0
footprint: [[ -0.146,  -0.372],
            [ 0.354, -0.372],
            [ 0.554, 0],
            [0.354, 0.372],
            [-0.146,  0.372]]
robot_radius: ir_of_robot
inflation_radius: 0.6
robot_radius: 0.5

observation_sources: laser

laser: {sensor_frame: laser, data_type: LaserScan, topic: /scan, marking: true, clearing: true}


  global_frame: /map
  robot_base_frame: /base_footprint
  update_frequency: 5.0
  static_map: true
  resolution: 0.05
  width: 0
  height: 10


  global_frame: /odom
  robot_base_frame: /base_footprint
  update_frequency: 5.0
  publish_frequency: 2.0
  static_map: false
  rolling_window: true
  width: 6.0
  height: 6.0
  resolution: 0.05

Originally posted by Morteza on ROS Answers with karma: 9 on 2015-01-13

Post score: 0

Original comments

Comment by David Lu on 2015-01-14:
I'm not sure I understand what the problem is. When the power is low, the configuration works but when the power is higher it doesn't? Does that just mean the robot is driving faster?

Comment by Morteza on 2015-01-14:
Thanks David for edition. No, this is not the problem. I computed the new acceleration and velocity of the robot when using battery and set them in the config. files. the robot doesn't move faster. The planner computes the global path well bu i see that the local planner gives wrong commands.

Comment by Morteza on 2015-01-14:
The wrong commands of the local planner causes the robot to go far from the global path or turn around and hits the obstacles.


1 Answer 1


Rosanswers logo

Are you perhaps specifying your rotation speed incorrectly? It should be in radians/s

Originally posted by David Lu with karma: 10932 on 2015-01-14

This answer was ACCEPTED on the original site

Post score: 0

Original comments

Comment by Morteza on 2015-01-14:
the approach i computed the rotation velocity is that at first i computed the maximum linear velocity of the robot and then doubled it and divide it by the distance between the wheels. 13.736 means that the robot can rotate twice (4 pi) in one second and i think it seems logical.

Comment by David Lu on 2015-01-14:
That's just faster than I expected.


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