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Ortiz et al. Intell Robot 2021;1(2):131-50  I http://dx.doi.org/10.20517/ir.2021.09     Page 145


                                                                               x
                                           x  g(x ,x )                          T
                                      100   i   i  j
                                       90
                                       80
                                       70
                                                    x
                                       60           S
                                     y [m]  50      f*

                                       40
                                       30
                                       20
                                       10
                                       0
                                        0   10  20  30   40  50  60  70  80  90  100
                                                            x [m]
                       Figure 9. Sliding mode simultaneous localization and mapping based path planning (bold) and grid method (gray).



                                        90
                                                                           Iter 40
                                        80
                                                                           Iter 30
                                                                           Iter 20
                                        70
                                                                           Iter 10
                                        60
                                        50
                                        40
                                        30
                                        20
                                        10
                                         0
                                         185   190    195   200    205   210    215
                                                        Histogram (RGA)
                                             Figure 10. Performance of the genetic algorithm.


               a solution    . Here, 60 local targets were generated       with the search space    generated by the trajectories of
                         ∗
               the local targets that do not intersect with the set of obstacles; thus, it became an optimization problem to find
               an optimal path.



               In an environment with previously generated obstacles of 100 m × 100 m, 120 possible targets were randomly
                                                                             ) that do not intersect with the set
               generated      ; therefore, the search space D would be all trajectories   (      ,      
               of obstacles, where the roadmap genetic algorithm solved the problem of optimization to find a solution to the
               problem of path planning. For the problem presented above, we found that the proposed algorithm converged
               in 40 iterations. For these results, 100 tests were performed for each number of iterations and, as shown in
               Figure 10, the roadmap genetic algorithm converged with greater probability within 40 iterations.


               5.2.  Application
               TheKoalamobilerobotbyK-teamCorporation2013wasused tovalidateourslidingmodeSLAM.Thismobile
               robot has encoders and one laser range finder. The position precision is less than 0.1 m.
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