cleanLiDARTargetCore.m

%{
 * Copyright (C) 2013-2020, The Regents of The University of Michigan.
 * All rights reserved.
 * This software was developed in the Biped Lab (https://www.biped.solutions/) 
 * under the direction of Jessy Grizzle, grizzle@umich.edu. This software may 
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 * AUTHOR: Bruce JK Huang (bjhuang[at]umich.edu)
 * WEBSITE: https://www.brucerobot.com/
%}

function [X_clean, X_ref, X_std, L_infinity, N] = cleanLiDARTargetCore(opt, X, target_len)
    N = 4; % clean up using N std for x axis
    M = 3; % clean up using M std for y, z axis
    opt = optimizeCost(opt, X, target_len, 0.001);
    X_ref = opt.H_opt * X;
%     distance = sum(X_ref(1:3,:), 1); % L1
    L_infinity = max(abs(X_ref(1:3,:)));  % L infinity
    K = find(L_infinity < (target_len/2)*1.025);
    X_ref_clean_yz = X_ref(:, K); % clean up y and z axis
    L_infinity = max(X_ref_clean_yz(1:3,:));
    K_center = find(L_infinity < target_len/4);
    X_std = std(X_ref_clean_yz(:, K_center), 1, 2);
    Q = find(abs(X_ref_clean_yz(1,:)) < N*(X_std(1))); % clean up x with 2 std
    X_ref_clean = X_ref_clean_yz(:, Q);
    X_clean = inv(opt.H_opt) * X_ref_clean;   
end