diff --git a/beacon.cc b/beacon.cc
index 653eb7f..bd6f1a9 100644
--- a/beacon.cc
+++ b/beacon.cc
@@ -6,17 +6,20 @@
 #include "random.hh"
 #include "vec_3d.hh"
 
+using namespace std;
+
 // Authors: Anastasios Zochios, Pavlos Tziranis
 
-beacon::beacon(std::string name, vec_3d location, double localError = 0.05,
-               double rangeError)
-    : name(name),
-      location(location),
-      localError(localError),
-      rangeError(rangeError) {}
+beacon::beacon(string name, double x, double y, double z)
+    : name(name), location(vec_3d(x, y, z)) {}
+
+// outputs the estimated location of the beacon updated with a normally
+// distrubuted error with mean=0 & std.dev = 2
+void beacon::estimate_loc() {
+  vec_3d error(N(0, 2), N(0, 2), N(0, 2));
+  estlocation = location + error;
+}
 
-// beacon::double detect_object(double power);
-/* Adding a scalar to a vector; vec_3d operator+ needs to initialize a scalar as
- * vector */
-friend ostream& operator<<(ostream& s, beacon a) {
-  return s << a.name << a.location + a.localError;
\ No newline at end of file
+ostream& operator<<(ostream& s, beacon a) {
+  return s << a.name << a.location + a.localError;
+}
\ No newline at end of file
diff --git a/beacon.hh b/beacon.hh
index cd0bf0f..1815dc1 100644
--- a/beacon.hh
+++ b/beacon.hh
@@ -3,19 +3,22 @@
 #include <iostream>
 #include <string>
 
+#include "random.hh"
 #include "vec_3d.hh"
 
 class beacon {
  private:
   std::string name;
-  vec_3d location;    // the real location of the beacon in the simulation (ground truth)
-  vec_3d estlocation; // the location the beacon believes it is in (with error, as in real life)
-  double localError;
-  double rangeError;
+  vec_3d location;  // the real location of the beacon in the simulation (ground
+                    // truth)
+  vec_3d estlocation;  // the location the beacon believes it is in (with error,
+                       // as in real life)
+                       // double localError;
+                       // double rangeError;
+  void estimate_loc();
 
  public:
-  beacon(std::string name, vec_3d location, double localError,
-         double rangeError);
+  beacon(std::string name, vec_3d location);
 
   friend std::ostream& operator<<(std::ostream& s, beacon a);
 };
diff --git a/quadcopter.cc b/quadcopter.cc
new file mode 100644
index 0000000..5b46c07
--- /dev/null
+++ b/quadcopter.cc
@@ -0,0 +1,31 @@
+#include "quadcopter.cc"
+
+class quadcopter : public robot {
+    public:
+        quadcopter(double x = 0, 
+            double y = 0, double z = 0, double hvar, double vvar, double hdg, double speed, double battlife) 
+            : robot(vec_3d(x, y, z), hvar, vvar, hdg, speed, battlife) {};
+
+        void loc_change(double dx, double dy, double dz);
+
+        void setThrottle(double h);
+
+        void setRaw(double r);
+
+        void setPitch(double p);
+
+        void setYaw(double w);
+
+        void setAirSpeed(double s);
+        
+        void update(double dt);
+
+        friend ostream& operator <<(ostream& s, const quadcopter& a);
+
+    private:
+        double throttle;
+        double raw;
+        double pitch;
+        double yaw; 
+        double airSpeed;
+};
diff --git a/quadcopter.hh b/quadcopter.hh
index cec5044..225b8aa 100644
--- a/quadcopter.hh
+++ b/quadcopter.hh
@@ -4,26 +4,31 @@
 #include <string>
 #include "robot.hh"
 
-using namespace std;
 
 class quadcopter : public robot {
     public:
-        quadcopter(const string& name, double x, double y, double z) : name(name), x(x), y(y), z(z) {}
-class quadcopter{
-    public:
-        quadcopter(const string& name, double x = 0, double y = 0, double z = 0) {}
+        quadcopter(double x, double y, double z, double hvar, double vvar, double hdg, double speed, double battlife);
+
         void loc_change(double dx, double dy, double dz);
+
         void setThrottle(double h);
+
         void setRaw(double r);
+
         void setPitch(double p);
+
         void setYaw(double w);
+
         void setAirSpeed(double s);
+        
         void update(double dt);
 
         friend ostream& operator <<(ostream& s, const quadcopter& a);
-}
+
     private:
-        string name;
-        double x, y, z;
-        double throttle, raw, pitch, yaw, airSpeed;
+        double throttle;
+        double raw;
+        double pitch;
+        double yaw; 
+        double airSpeed;
 };