RRT* with a double integrator on the plane using the libbot interface for visualization. This file provides the code for running the RRT* algorithm for a double integrator model in two dimensions. This model involves a system with differential constraints with a 4-dimensional state space and under-actuation.
// Standard header files #include<iostream> using namespace std; // SMP HEADER FILES ------ #include <smp/components/extenders/double_integrator.hpp> #include <smp/components/samplers/uniform.hpp> #include <smp/components/collision_checkers/standard.hpp> #include <smp/components/distance_evaluators/kdtree.hpp> #include <smp/components/multipurpose/minimum_time_reachability.hpp> #include <smp/planners/rrtstar.hpp> #include <smp/planner_utils/trajectory.hpp> #include <smp/interfaces/libbot.hpp> // SMP TYPE DEFINITIONS ------- using namespace smp; // State, input, vertex_data, and edge_data definitions typedef state_double_integrator<2> state_t; typedef input_double_integrator<2> input_t; typedef minimum_time_reachability_vertex_data vertex_data_t; typedef minimum_time_reachability_edge_data edge_data_t; // Create the typeparams structure typedef struct _typeparams { typedef state_t state; typedef input_t input; typedef vertex_data_t vertex_data; typedef edge_data_t edge_data; } typeparams; // Define the trajectory type typedef trajectory<typeparams> trajectory_t; // Define all planner component types typedef sampler_uniform<typeparams,4> sampler_t; typedef distance_evaluator_kdtree<typeparams,4> distance_evaluator_t; typedef extender_double_integrator<typeparams,2> extender_t; typedef collision_checker_standard<typeparams,4> collision_checker_t; typedef minimum_time_reachability<typeparams,4> min_time_reachability_t; // Define all algorithm types typedef rrtstar<typeparams> rrtstar_t; // Define interface types typedef interface_libbot<typeparams> interface_t; typedef interface_libbot_environment environment_t; int main () { // 1. CREATE PLANNING OBJECTS // 1.a Create the components sampler_t sampler; distance_evaluator_t distance_evaluator; extender_t extender; collision_checker_t collision_checker; min_time_reachability_t min_time_reachability; // 1.b Create the planner algorithm -- Note that the min_time_reachability variable acts both // as a model checker and a cost evaluator. rrtstar_t planner (sampler, distance_evaluator, extender, collision_checker, min_time_reachability, min_time_reachability); planner.parameters.set_phase (2); // The phase parameter can be used to run the algorithm as an RRT, // See the documentation of the RRT* algorithm for more information. planner.parameters.set_gamma (25.0); // Set this parameter should be set at least to the side length of // the (bounded) state space. E.g., if the state space is a box // with side length L, then this parameter should be set to at // least L for rapid and efficient convergence in trajectory space. planner.parameters.set_dimension (4); // Double integrator state space is four dimensional. planner.parameters.set_max_radius (20.0); // This variable is basically set to a high engouh value. // 1.c Create the visualization interface interface_t interface; // 2. INITALIZE PLANNING OBJECTS // 2.a Initialize the sampler region<4> sampler_support; for (int i = 0; i < 2; i++) { sampler_support.center[i] = 0.0; sampler_support.size[i] = 20.0; } for (int i = 2; i < 4; i++) { sampler_support.center[i] = 0.0; sampler_support.size[i] = 2.0; } sampler.set_support (sampler_support); // 2.b Initialize the distance evaluator // Nothing to initialize. One could change the kdtree weights. // 2.c Initialize the extender // 2.d Initialize the collision checker region<4> obstacle_new; for (int i = 0; i < 2; i++) { obstacle_new.center[i] = 5.0; obstacle_new.size[i] = 5.0; } for (int i = 2; i < 4; i++) { obstacle_new.center[i] = 0.0; obstacle_new.size[i] = 20.0; } collision_checker.add_obstacle (obstacle_new); // 2.e Initialize the model checker region<4> region_goal; for (int i = 0; i < 2; i++) { region_goal.center[i] = 8.0; region_goal.size[i] = 2.0; } for (int i = 2; i < 4; i++) { region_goal.center[i] = 0.0; region_goal.size[i] = 20.0; } min_time_reachability.set_goal_region (region_goal); // 2.f Initialize the planner state_t *state_initial = new state_t; for (int i = 0; i < 4; i++) { state_initial->state_vars[i] = 0.0; } planner.initialize (state_initial); // 2.g Initialize the libbot interface. interface.set_planner (&planner); interface.visualize_2d(); // 3. PUBLISH THE ENVIRONMENT AS A MESAGE THROUGH THE INTERFACE environment_t environment; region<3> goal; goal.center[0] = 8.0; goal.center[1] = 8.0; goal.center[2] = 0.5; goal.size[0] = 2.0; goal.size[1] = 2.0; goal.size[2] = 1.0; environment.set_goal_region (goal); region<3> operating; operating.center[0] = 0.0; operating.center[1] = 0.0; operating.center[2] = 5.0; operating.size[0] = 20.0; operating.size[1] = 20.0; operating.size[2] = 10.0; environment.set_operating_region (operating); region<3> obstacle; obstacle.center[0] = 5.0; obstacle.center[1] = 5.0; obstacle.center[2] = 1.0; obstacle.size[0] = 5.0; obstacle.size[1] = 5.0; obstacle.size[2] = 2.0; environment.add_obstacle (obstacle); interface.publish_environment (environment); // 4. RUN THE PLANNER for (int i = 0; i < 1000; i++){ planner.iteration (); if (i%10 == 0){ cout << "Iteration : " << i << endl; interface.publish_data (); } } // 5. PUBLISH THE RESULTS THROUGH THE LIBBOT INTERFACE interface.publish_data (); trajectory_t trajectory_final; min_time_reachability.get_solution (trajectory_final); interface.publish_trajectory (trajectory_final); return 1; }
