Geometry models

Python

import pinocchio
from sys import argv
from os.path import dirname, join, abspath
 
# This path refers to Pinocchio source code but you can define your own directory here.
pinocchio_model_dir = join(dirname(dirname(str(abspath(__file__)))), "models")
 
model_path = join(pinocchio_model_dir,"example-robot-data/robots") if len(argv)<2 else argv[1]
mesh_dir = pinocchio_model_dir
urdf_model_path = join(model_path,"ur_description/urdf/ur5_robot.urdf")
 
# Load the urdf model
model, collision_model, visual_model = pinocchio.buildModelsFromUrdf(urdf_model_path, mesh_dir)
print('model name: ' + model.name)
 
# Create data required by the algorithms
data, collision_data, visual_data  = pinocchio.createDatas(model, collision_model, visual_model)
 
# Sample a random configuration
q        = pinocchio.randomConfiguration(model)
print('q: %s' % q.T)
 
# Perform the forward kinematics over the kinematic tree
pinocchio.forwardKinematics(model,data,q)
 
# Update Geometry models
pinocchio.updateGeometryPlacements(model, data, collision_model, collision_data)
pinocchio.updateGeometryPlacements(model, data, visual_model, visual_data)
 
# Print out the placement of each joint of the kinematic tree
print("\nJoint placements:")
for name, oMi in zip(model.names, data.oMi):
    print(("{:<24} : {: .2f} {: .2f} {: .2f}"
          .format( name, *oMi.translation.T.flat )))
 
# Print out the placement of each collision geometry object
print("\nCollision object placements:")
for k, oMg in enumerate(collision_data.oMg):
    print(("{:d} : {: .2f} {: .2f} {: .2f}"
          .format( k, *oMg.translation.T.flat )))
 
# Print out the placement of each visual geometry object
print("\nVisual object placements:")
for k, oMg in enumerate(visual_data.oMg):
    print(("{:d} : {: .2f} {: .2f} {: .2f}"
          .format( k, *oMg.translation.T.flat )))

C++

#include "pinocchio/multibody/fcl.hpp"
#include "pinocchio/parsers/urdf.hpp"
 
#include "pinocchio/algorithm/joint-configuration.hpp"
#include "pinocchio/algorithm/kinematics.hpp"
#include "pinocchio/algorithm/geometry.hpp"
 
#include <iostream>
 
// PINOCCHIO_MODEL_DIR is defined by the CMake but you can define your own directory here.
#ifndef PINOCCHIO_MODEL_DIR
  #define PINOCCHIO_MODEL_DIR "path_to_the_model_dir"
#endif
 
int main(int argc, char ** argv)
{
  using namespace pinocchio;
 
  const std::string model_path = (argc<=1) ? PINOCCHIO_MODEL_DIR + std::string("/example-robot-data/robots") : argv[1];
  const std::string mesh_dir = (argc<=1) ? PINOCCHIO_MODEL_DIR : argv[1];
  const std::string urdf_filename = model_path + "/ur_description/urdf/ur5_robot.urdf";
 
  // Load the urdf model
  Model model;
  pinocchio::urdf::buildModel(urdf_filename,model);
  GeometryModel collision_model;
  pinocchio::urdf::buildGeom(model, urdf_filename, COLLISION, collision_model, mesh_dir);
  GeometryModel visual_model;
  pinocchio::urdf::buildGeom(model, urdf_filename, VISUAL, visual_model, mesh_dir);
  std::cout << "model name: " << model.name << std::endl;
 
  // Create data required by the algorithms
  Data data(model);
  GeometryData collision_data(collision_model);
  GeometryData visual_data(visual_model);
 
  // Sample a random configuration
  Eigen::VectorXd q = randomConfiguration(model);
  std::cout << "q: " << q.transpose() << std::endl;
 
  // Perform the forward kinematics over the kinematic tree
  forwardKinematics(model,data,q);
 
  // Update Geometry models
  updateGeometryPlacements(model, data, collision_model, collision_data);
  updateGeometryPlacements(model, data, visual_model, visual_data);
 
  // Print out the placement of each joint of the kinematic tree
  std::cout << "\nJoint placements:" << std::endl;
  for(JointIndex joint_id = 0; joint_id < (JointIndex)model.njoints; ++joint_id)
    std::cout << std::setw(24) << std::left
              << model.names[joint_id] << ": "
              << std::fixed << std::setprecision(2)
              << data.oMi[joint_id].translation().transpose()
              << std::endl;
 
  // Print out the placement of each collision geometry object
  std::cout << "\nCollision object placements:" << std::endl;
  for(GeomIndex geom_id = 0; geom_id < (GeomIndex)collision_model.ngeoms; ++geom_id)
    std::cout << geom_id << ": "
              << std::fixed << std::setprecision(2)
              << collision_data.oMg[geom_id].translation().transpose()
              << std::endl;
 
  // Print out the placement of each visual geometry object
  std::cout << "\nVisual object placements:" << std::endl;
  for(GeomIndex geom_id = 0; geom_id < (GeomIndex)visual_model.ngeoms; ++geom_id)
    std::cout << geom_id << ": "
              << std::fixed << std::setprecision(2)
              << visual_data.oMg[geom_id].translation().transpose()
              << std::endl;
}