ik_solver.h

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#ifndef EXOTICA_IK_SOLVER_IK_SOLVER_H_
#define EXOTICA_IK_SOLVER_IK_SOLVER_H_
 
#include <exotica_core/motion_solver.h>
#include <exotica_core/problems/unconstrained_end_pose_problem.h>
 
#include <exotica_ik_solver/ik_solver_initializer.h>
 
namespace exotica
{
class IKSolver : public MotionSolver, public Instantiable<IKSolverInitializer>
{
public:
    void Solve(Eigen::MatrixXd& solution) override;
    void SpecifyProblem(PlanningProblemPtr pointer) override;
 
private:
    UnconstrainedEndPoseProblemPtr prob_;  // Shared pointer to the planning problem.
 
    Eigen::MatrixXd W_inv_;        
    Eigen::VectorXd alpha_space_;  
 
    // Pre-allocation of variables used during optimisation
    double stop_;                                  
    double step_;                                  
    double lambda_ = 0;                            
    double steplength_;                            
    Eigen::VectorXd q_;                            
    Eigen::VectorXd qd_;                           
    Eigen::VectorXd yd_;                           
    Eigen::MatrixXd cost_jacobian_;                
    Eigen::MatrixXd J_pseudo_inverse_;             
    double error_;                                 
    double error_prev_;                            
    Eigen::LLT<Eigen::MatrixXd> J_decomposition_;  
    Eigen::MatrixXd J_tmp_;                        
 
    // Convergence thresholds
    double th_stop_;  
 
    // Regularization
    double regmin_ = 1e-9;     
    double regmax_ = 1e9;      
    double regfactor_ = 10.;   
    double th_stepdec_ = 0.5;  
    double th_stepinc_ = 0.1;  
 
    void IncreaseRegularization()
    {
        lambda_ *= regfactor_;
        if (lambda_ > regmax_)
        {
            lambda_ = regmax_;
        }
    }
 
    void DecreaseRegularization()
    {
        lambda_ /= regfactor_;
        if (lambda_ < regmin_)
        {
            lambda_ = regmin_;
        }
    }
 
    void PrintDebug(const int i)
    {
        if (i % 10 == 0 || i == 0)
        {
            std::cout << "iter \t cost \t       stop \t    grad \t  reg \t step\n";
        }
 
        std::cout << std::setw(4) << i << "  ";
        std::cout << std::scientific << std::setprecision(5) << error_ << "  ";
        std::cout << step_ << "  " << stop_ << "  ";
        std::cout << lambda_ << "  ";
        std::cout << std::fixed << std::setprecision(4) << steplength_ << '\n';
    }
 
    void ScaleToStepSize(Eigen::VectorXdRef xd);  
};
}  // namespace exotica
 
#endif  // EXOTICA_IK_SOLVER_IK_SOLVER_H_