fixed issues in sigmoid sensor model causing inverted response (annular partitions)

sensorModels/@sigmoidSensor/distanceMembership.m

@@ -0,0 +1,10 @@
+function x = distanceMembership(obj, d)
+    arguments (Input)
+        obj (1, 1) {mustBeA(obj, 'sigmoidSensor')};
+        d (:, 1) double;
+    end
+    arguments (Output)
+        x (:, 1) double;
+    end
+    x = 1 - (1 ./ (1 + exp(-obj.betaDist .* (abs(d) - obj.alphaDist))));
+end

sensorModels/@sigmoidSensor/initialize.m

@@ -0,0 +1,21 @@
+function obj = initialize(obj, alphaDist, betaDist, alphaPan, betaPan, alphaTilt, betaTilt)
+    arguments (Input)
+        obj (1, 1) {mustBeA(obj, 'sigmoidSensor')}
+        alphaDist (1, 1) double;
+        betaDist (1, 1) double;
+        alphaPan (1, 1) double;
+        betaPan (1, 1) double;
+        alphaTilt (1, 1) double;
+        betaTilt (1, 1) double;
+    end
+    arguments (Output)
+        obj (1, 1) {mustBeA(obj, 'sigmoidSensor')}
+    end
+    
+    obj.alphaDist = alphaDist;
+    obj.betaDist = betaDist;
+    obj.alphaPan = alphaPan;
+    obj.betaPan = betaPan;
+    obj.alphaTilt = alphaTilt;
+    obj.betaTilt = betaTilt;
+end

sensorModels/@sigmoidSensor/plotParameters.m

@@ -0,0 +1,42 @@
+function f = plotParameters(obj)
+    arguments (Input)
+        obj (1, 1) {mustBeA(obj, 'sigmoidSensor')};
+    end
+    arguments (Output)
+        f (1, 1) {mustBeA(f, 'matlab.ui.Figure')};
+    end
+
+    % Distance and tilt sample points
+    d = 0:(obj.alphaDist / 100):(2*obj.alphaDist);
+    t = -90:1:90;
+
+    % Sample membership functions
+    d_x = obj.distanceMembership(d);
+    t_x = obj.tiltMembership(t);
+
+    % Plot resultant sigmoid curves
+    f = figure;
+    tiledlayout(f, 2, 1, "TileSpacing", "tight", "Padding", "compact");
+
+    % Distance
+    nexttile(1, [1,  1]);
+    grid("on");
+    title("Distance Membership Sigmoid");
+    xlabel("Distance (m)");
+    ylabel("Membership");
+    hold('on');
+    plot(d, d_x, 'LineWidth', 2);
+    hold('off');
+    ylim([0, 1]);
+
+    % Tilt
+    nexttile(2, [1,  1]);
+    grid("on");
+    title("Tilt Membership Sigmoid");
+    xlabel("Tilt (deg)");
+    ylabel("Membership");
+    hold('on');
+    plot(t, t_x, 'LineWidth', 2);
+    hold('off');
+    ylim([0, 1]);
+end

sensorModels/@sigmoidSensor/sense.m

@@ -0,0 +1,21 @@
+function [values, positions] = sense(obj, agent, sensingObjective, domain, partitioning)
+    arguments (Input)
+        obj (1, 1) {mustBeA(obj, 'sigmoidSensor')};
+        agent (1, 1) {mustBeA(agent, 'agent')};
+        sensingObjective (1, 1) {mustBeA(sensingObjective, 'sensingObjective')};
+        domain (1, 1) {mustBeGeometry};
+        partitioning (:, :) double;
+    end
+    arguments (Output)
+        values (:, 1) double;
+        positions (:, 3) double;
+    end
+
+    % Find positions for this agent's assigned partition in the domain
+    idx = partitioning == agent.index;
+    positions = [sensingObjective.X(idx), sensingObjective.Y(idx), zeros(size(sensingObjective.X(idx)))];
+
+    % Evaluate objective function at every point in this agent's
+    % assigned partiton
+    values = sensingObjective.values(idx);
+end

sensorModels/@sigmoidSensor/sensorPerformance.m

@@ -0,0 +1,22 @@
+function value = sensorPerformance(obj, agentPos, agentPan, agentTilt, targetPos)
+    arguments (Input)
+        obj (1, 1) {mustBeA(obj, 'sigmoidSensor')};
+        agentPos (1, 3) double;
+        agentPan (1, 1) double;
+        agentTilt (1, 1) double;
+        targetPos (:, 3) double;
+    end
+    arguments (Output)
+        value (:, 1) double;
+    end
+
+    d = vecnorm(agentPos - targetPos, 2, 2); % distance from sensor to target
+    x = vecnorm(agentPos(1:2) - targetPos(:, 1:2), 2, 2); % distance from sensor nadir to target nadir (i.e. distance ignoring height difference)
+    tiltAngle = (180 - atan2d(x, targetPos(:, 3) - agentPos(3))) - agentTilt; % degrees
+
+    % Membership functions
+    mu_d = obj.distanceMembership(d);
+    mu_t = obj.tiltMembership(tiltAngle);
+
+    value = mu_d .* mu_t; % assume pan membership is always 1
+end

sensorModels/@sigmoidSensor/sigmoidSensor.m

@@ -0,0 +1,22 @@
+classdef sigmoidSensor
+    properties (SetAccess = private, GetAccess = public)
+        % Sensor parameters
+        alphaDist = NaN;
+        betaDist = NaN;
+        alphaPan = NaN;
+        betaPan = NaN;
+        alphaTilt = NaN; % degrees
+        betaTilt = NaN;
+    end
+
+    methods (Access = public)
+        [obj]               = initialize(obj, alphaDist, betaDist, alphaPan, betaPan, alphaTilt, betaTilt);
+        [values, positions] = sense(obj, agent, sensingObjective, domain, partitioning);
+        [value]             = sensorPerformance(obj, agentPos, agentPan, agentTilt, targetPos);
+        [f] = plotParameters(obj);
+    end
+    methods (Access = private)
+        x = distanceMembership(obj, d);
+        x = tiltMembership(obj, t);
+    end
+end

sensorModels/@sigmoidSensor/tiltMembership.m

@@ -0,0 +1,10 @@
+function x = tiltMembership(obj, t)
+    arguments (Input)
+        obj (1, 1) {mustBeA(obj, 'sigmoidSensor')};
+        t (:, 1) double; % degrees
+    end
+    arguments (Output)
+        x (:, 1) double;
+    end
+    x = (1 ./ (1 + exp(-obj.betaTilt .* (t + obj.alphaTilt)))) - (1 ./ (1 + exp(-obj.betaTilt .* (t - obj.alphaTilt))));
+end