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

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