HebiTrajectory represents a precomputed trajectory path
 
    Trajectories are created by a HebiTrajectoryGenerator and provide
    a way to asynchronously move through a trajectory and to
    visualize the planned path.
 
    HebiTrajectory Methods:
       getStartTime    - returns the start time [s]
       getEndTime      - returns the end time [s]
       getDuration     - returns the total duration [s]
       getState        - returns position/velocity/acceleration 
                         at any given time.
       getWaypointTime - returns the timestamp for each waypoint
 
    Example
       % Create trajectory
       trajGen = HebiTrajectoryGenerator(kin);
       trajectory = trajGen.newJointMove([start; finish]);
 
       % Visualize trajectory
       t = 0:0.01:trajectory.getDuration();
       [pos, vel, accel] = trajectory.getState(t);
       HebiUtils.plotTrajectory(trajectory);
 
       % Manually execute position/velocity/effort trajectory
        cmd = CommandStruct();
        t0 = tic();
        t = toc(t0);
        while t < trajectory.getDuration()
            fbk = group.getNextFeedback();
 
            % get state at current time interval
            t = toc(t0);
            [pos, vel, accel] = trajectory.getState(t);
 
            % compensate for gravity
            gravityVec = -[fbk.accelX(1) fbk.accelY(1) fbk.accelZ(1)];
            gravCompEffort = kin.getGravCompEfforts(fbk.position, gravityVec);
 
            % compensate for accelerations
            accelCompEffort = kin.getDynamicCompEfforts(...
                fbk.position, ... % Used for calculating jacobian
                pos, vel, accel);
 
            % send to hardware
            cmd.position = pos;
            cmd.velocity = vel;
            cmd.effort = gravCompEffort + accelCompEffort;
            group.send(cmd);
  
       end