diff --git a/Roboid.cpp b/Roboid.cpp
index 2ea020d..5c9d511 100644
--- a/Roboid.cpp
+++ b/Roboid.cpp
@@ -14,9 +14,11 @@ Roboid::Roboid() {
 
 Roboid::Roboid(Perception *perception, Propulsion *propulsion) : Roboid() {
   this->perception = perception;
-  perception->roboid = this;
+  if (perception != nullptr)
+    perception->roboid = this;
   this->propulsion = propulsion;
-  propulsion->roboid = this;
+  if (propulsion != nullptr)
+    propulsion->roboid = this;
 }
 
 Roboid::Roboid(ServoMotor **actuation) : actuation(actuation) {}