Note: This tutorial assumes that you have read tutorial 1, as it shares the same code base.. |
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How to activate loop closure optimization (tutorial2.cpp)
Description: This tutorial describe how to set the internal solver inside Karto to activate the loop closure mechanism. It's based on the file tutorial2.cppTutorial Level: INTERMEDIATE
Contents
What does it do ?
This tutorials shows you how to add a loop closure solver (in this case ROS SPA) to correct the map in the event of a loop closure. If you are not setting the solver, the loop closure will not happen.
Show me the code ?
The entire code for this tutorial is in the samples directory and is appropriately called tutorial2.cpp
Setting the solver
Karto can use several loop-closure solvers, the current best one is called SPA (Sparse Pose Adjustment) in the sba ROS package. The other solvers that have been tested but are not included are PCG (Preconditioned Conjugate Gradient) and TORO.
To activate SPA in Karto:
What is the correct output of tutorial1 ?
$ ./tutorial2 Registering sensor: laser0 Pose: 0 0 0 Corrected Pose: 0 0 0 Pose: 1 0 1.57 Corrected Pose: 0.799804 -0.156715 1.48971 Pose: 1 -1 2.35619 Corrected Pose: 0.756943 -1.03575 2.27242 Generating map... width = 69, height = 68, scale = 10, offset: -2.8885, -3 ****************************XXX XXXX******************** *************************XXX XXX****************** ***********************XXX * * * XX**************** **********************XX * *XX************** ********************XX* *X************* *******************X* * * * *XX*********** ******************X* * * *XX********** *****************X* * * XXXXXX * * * *XX********* ****************X* * * XXXXX * * XX******** ***************X* * * * * XXX * * XX******* **************X* * * *XXXXXXXXXXXXXXX XXX * *X******* *************X* * * XXXX XXXX * XXX* * *X****** *************X XXX XX XX *X***** ************X* XX XX XX* * X***** ***********XX XX * XX *XX *X**** ***********XXXX XX XX* X**** **********XXX XX XX X*** **********XX XX XX X*** *********XX XX X * X** ********XX * X *X X** *******XXX XX XX X** ******XX X X* X* ******X*XX X X* *****X* X XXX* ****XX X XX* ****X* *X XX* ***X* *X XX ***X * * XX **XX* * * XX **X * * ** * X **X * X *X * X *X * X *X *X * X * ** X *** X **** X ****** X ******* X ******** X ********* X ********** X X ************ X X ************* X XX * ************** * * X *X *************** *XX *X **************** * X* *X * * ****************** * * X* *XX* ******************* X** **X * ******************** * * X** **X * * * ********************* * * * X*** ***X ********************** * * * *X*** ***X ************************ * * * * X**** ****X * * ************************* * * XX**** ****X* * * ************************** * * * * * *X***** *****X * *************************** * * * *X****** *****XX * **************************** * * *X******* ******X* ****************************** * * *X******** *******X******************************* * * *XX******** *************************************** * *X********** *************************************** * ** *X*********** *************************************** *XX************ *************************************** ** XX************** *************************************** * * XXX*************** *************************************** XXXX***************** *************************************** XXXXX******************** ***************************************XXXXXX************************