Trilateration on Android with iBeacons

Question

We want to implement some kind of definition of the internal situation using iBeacons. This article seems really interesting in which the author implemented Non-Linear Least Square Triangulation using the Eigen C ++ library and Levenberg Marquardt algorithm. Since Eigen is written in C ++, I tried to use JNI and Android NDK to use it, but it chose the number of errors that I don’t know how to solve and I couldn’t find anything on the Internet. I also tried using Jeigen, but it does not have all the features we need.

So my questions are:

• Has anyone ever implemented any use of Trilateration beacons in Android?

• Do you think using Eigen + JNI + NDK is a good solution? If so, have you ever implemented Levenberg Marquardt using a combination?

• Are there any better options than the Levenberg Marquardt algorithm for calculating trilateration in an Android application?

Answer 1

Take a look at this library: https://github.com/lemmingapex/Trilateration

uses the Levenberg-Marquardt algorithm from Apache Commons Math.

For example .. in TrilaterationTest.java

You can see:

double[][] positions = new double[][] { { 1.0, 1.0 }, { 2.0, 1.0 } }; double[] distances = new double[] { 0.0, 1.0 }; TrilaterationFunction trilaterationFunction = new TrilaterationFunction(positions, distances); NonLinearLeastSquaresSolver solver = new NonLinearLeastSquaresSolver(trilaterationFunction, new LevenbergMarquardtOptimizer()); double[] expectedPosition = new double[] { 1.0, 1.0 }; Optimum optimum = solver.solve(); testResults(expectedPosition, 0.0001, optimum); 

but if you see an example objectivec https://github.com/RGADigital/indoor_navigation_iBeacons/blob/show-work/ios/Group5iBeacons/Debug/Managers/Location/NonLinear/NonLinear.mm , you can notice that the accuracy is used as an evaluation parameter rather than distance.