Once we have the costmaps configured, it is necessary to configure the base planner. The base planner is used to generate the velocity commands to move our robot. Create a new file in chapter6_tutorials/launch with the name base_local_planner_params.yaml, and add the following code:
TrajectoryPlannerROS: max_vel_x: 0.2 min_vel_x: 0.05 max_rotational_vel: 0.15 min_in_place_rotational_vel: 0.01 min_in_place_vel_theta: 0.01 max_vel_theta: 0.15 min_vel_theta: -0.15 acc_lim_th: 3.2 acc_lim_x: 2.5 acc_lim_y: 2.5 holonomic_robot: false
The config file will set the maximum and minimum velocities for your robot. The acceleration is also set.
The holonomic_robot parameter is true if you are using a holonomic platform. In our case, our robot is based on a non-holonomic platform and the parameter is set to false. A holonomic vehicle is one that can move in all the configured space from any position. In other words, if the places where the robot can go are defined by any x and y values in the environment, this means that the robot can move there from any position. For example, if the robot can move forward, backward, and laterally, it is holonomic. A typical case of a non-holonomic vehicle is a car, as it cannot move laterally, and from a given position, there are many other positions (or poses) that are not reachable. Also, a differential platform is non-holonomic.