trajectory_example.cpp

Go to the documentation of this file.

#include <frames.hpp>
#include <frames_io.hpp>
#include <trajectory.hpp>
#include <trajectory_segment.hpp>
#include <trajectory_stationary.hpp>
#include <trajectory_composite.hpp>
#include <trajectory_composite.hpp>
#include <velocityprofile_trap.hpp>
#include <path_roundedcomposite.hpp>
#include <rotational_interpolation_sa.hpp>
#include <utilities/error.h>
#include <utilities/utility.h>
#include <trajectory_composite.hpp>

int main(int argc,char* argv[]) {
    using namespace KDL;
    // Create the trajectory:
    // use try/catch to catch any exceptions thrown.
    // NOTE:  exceptions will become obsolete in a future version.
    try {
        // Path_RoundedComposite defines the geometric path along
        // which the robot will move.
        //
        Path_RoundedComposite* path = new Path_RoundedComposite(0.2,0.01,new RotationalInterpolation_SingleAxis());
        // The routines are now robust against segments that are parallel.
        // When the routines are parallel, no rounding is needed, and no attempt is made
        // add constructing a rounding arc.
        // (It is still not possible when the segments are on top of each other)
        // Note that you can only rotate in a deterministic way over an angle less then PI!
        // With an angle == PI, you cannot predict over which side will be rotated.
        // With an angle > PI, the routine will rotate over 2*PI-angle.
        // If you need to rotate over a larger angle, you need to introduce intermediate points.
        // So, there is a common use case for using parallel segments.
        path->Add(Frame(Rotation::RPY(PI,0,0), Vector(-1,0,0)));
        path->Add(Frame(Rotation::RPY(PI_2,0,0), Vector(-0.5,0,0)));
        path->Add(Frame(Rotation::RPY(0,0,0), Vector(0,0,0)));
        path->Add(Frame(Rotation::RPY(0.7,0.7,0.7), Vector(1,1,1)));
        path->Add(Frame(Rotation::RPY(0,0.7,0), Vector(1.5,0.3,0)));
        path->Add(Frame(Rotation::RPY(0.7,0.7,0), Vector(1,1,0)));

        // always call Finish() at the end, otherwise the last segment will not be added.
        path->Finish();

        // Trajectory defines a motion of the robot along a path.
        // This defines a trapezoidal velocity profile.
        VelocityProfile* velpref = new VelocityProfile_Trap(0.5,0.1);
        velpref->SetProfile(0,path->PathLength());  
        Trajectory* traject = new Trajectory_Segment(path, velpref);


        Trajectory_Composite* ctraject = new Trajectory_Composite();
        ctraject->Add(traject);
        ctraject->Add(new Trajectory_Stationary(1.0,Frame(Rotation::RPY(0.7,0.7,0), Vector(1,1,0))));

        // use the trajectory
        double dt=0.1;
        std::ofstream of("./trajectory.dat");
        for (double t=0.0; t <= traject->Duration(); t+= dt) {
            Frame current_pose;
            current_pose = traject->Pos(t);
            for (int i=0;i<4;++i)
                for (int j=0;j<4;++j)
                    of << current_pose(i,j) << "\t";
            of << "\n";
            // also velocities and accelerations are available !
            //traject->Vel(t);
            //traject->Acc(t);
        }
        of.close();

        // you can get some meta-info on the path:
        for (int segmentnr=0;  segmentnr < path->GetNrOfSegments(); segmentnr++) {
            double starts,ends;
            Path::IdentifierType pathtype;
            if (segmentnr==0) {
                starts = 0.0;
            } else {
                starts = path->GetLengthToEndOfSegment(segmentnr-1);
            }
            ends = path->GetLengthToEndOfSegment(segmentnr);
            pathtype = path->GetSegment(segmentnr)->getIdentifier();
            std::cout << "segment " << segmentnr << " runs from s="<<starts << " to s=" <<ends;
            switch(pathtype) {
                case Path::ID_CIRCLE:
                    std::cout << " circle";
                    break;
                case Path::ID_LINE:
                    std::cout << " line ";
                    break;
                default:
                    std::cout << " unknown ";
                    break;
            }
            std::cout << std::endl;
        }
        std::cout << " trajectory written to the ./trajectory.dat file " << std::endl;

        delete ctraject;
    } catch(Error& error) {
        std::cout <<"I encountered this error : " << error.Description() << std::endl;
        std::cout << "with the following type " << error.GetType() << std::endl;
    }

}