approx_friction_map

approx_friction_map(reftrack, normvectors, tpamap_path, tpadata_path, pars, dn, n_gauss, print_debug, plot_debug)

Created by: Fabian Christ

Documentation: A simplified dependency between the friction coefficients (mue) and the lateral distance to the reference line (n) is obtained for each wheel along the racetrack. For this purpose friction coefficients are determined for a fine grid on the normal vectors from the friction map. Then the dependency between the extracted friction coefficients and the decision variable n for each path coordinate s_k is described by linear equations (var_friction: "lienar") or by linear regression with gaussian basis functions (var_friction: "gauss").

Inputs: reftrack: track [x_m, y_m, w_tr_right_m, w_tr_left_m] normvectors: array containing normalized normal vectors for every traj. point [x_component, y_component] tpamap_path: file path to tpa map (required for friction map loading) tpadata_path: file path to tpa data (required for friction map loading) pars: parameters dictionary dn: distance of equidistant points on normal vectors for extracting the friction coefficients n_gauss: number of gaussian basis functions on each side (n_gauss_tot = 2 * n_gauss + 1) print_debug: determines if debug prints are shown plot_debug: determines if debug plots are shown

Outputs: w_mue_fl: parameters for friction map approximation along the racetrack (left front wheel) w_mue_fr: parameters for friction map approximation along the racetrack (right front wheel) w_mue_rl: parameters for friction map approximation along the racetrack (left rear wheel) w_mue_rr: parameters for friction map approximation along the racetrack (right rear wheel) center_dist distance between two gaussian basis functions along the racetrack (only for var_friction: "gauss")