diff --git a/@sigmoidSensor/sigmoidSensor.m b/@sigmoidSensor/sigmoidSensor.m
index 958e9f2..81a23e3 100644
--- a/@sigmoidSensor/sigmoidSensor.m
+++ b/@sigmoidSensor/sigmoidSensor.m
@@ -5,6 +5,10 @@ classdef sigmoidSensor
         betaDist = NaN;
         alphaTilt = NaN; % degrees
         betaTilt = NaN;
+
+        % pointing parameters
+        tilt = 0;
+        azimuth = 0;
     end
 
     methods (Access = public)
diff --git a/util/objectiveFunctionWrapper.m b/util/objectiveFunctionWrapper.m
index 6846ffe..0a9de95 100644
--- a/util/objectiveFunctionWrapper.m
+++ b/util/objectiveFunctionWrapper.m
@@ -4,7 +4,7 @@ function f = objectiveFunctionWrapper(center, sigma)
     % composite objectives in particular
     arguments (Input)
         center (:, 2) double;
-        sigma (:, 2, 2) double = eye(2);
+        sigma (:, 2, 2) double = reshape(eye(2), 1, 2, 2);
     end
     arguments (Output)
         f (1, 1) {mustBeA(f, "function_handle")};
diff --git a/util/validators/arguments/mustBeSensor.m b/util/validators/arguments/mustBeSensor.m
index 6166995..df37919 100644
--- a/util/validators/arguments/mustBeSensor.m
+++ b/util/validators/arguments/mustBeSensor.m
@@ -1,11 +1,11 @@
 function mustBeSensor(sensorModel)
     if isa(sensorModel, 'cell')
         for ii = 1:size(sensorModel, 1)
-            assert(isa(sensorModel{ii}, 'sigmoidSensor'), ...
+            assert(isa(sensorModel{ii}, 'sigmoidSensor', 'rfSensor'), ...
                    'Sensor in index %d is not a valid sensor class', ii);
         end
     else
-        assert(isa(sensorModel, 'sigmoidSensor'), ...
+        assert(isa(sensorModel, 'sigmoidSensor') || isa(sensorModel, 'rfSensor'), ...
                'Sensor is not a valid sensor class');
     end
 end
\ No newline at end of file