diff --git a/exercises/robot-simulator/example.js b/exercises/robot-simulator/example.js
index f086a79ec8..e4d9c48188 100644
--- a/exercises/robot-simulator/example.js
+++ b/exercises/robot-simulator/example.js
@@ -1,3 +1,10 @@
+export class InvalidInputError extends Error {
+  constructor(message) {
+    super();
+    this.message = message || 'Invalid Input';
+  }
+}
+
 class Robot {
   constructor() {
     this.coordinates = [0, 0];
@@ -9,6 +16,11 @@ class Robot {
   }
 
   orient(direction) {
+    const validDirections = ['north', 'south', 'east', 'west'];
+    if (!validDirections.includes(direction)) {
+      throw new InvalidInputError('Invalid Robot Bearing');
+    }
+
     this.bearing = direction;
     return `The robot is pointed ${direction}`;
   }
diff --git a/exercises/robot-simulator/robot-simulator.spec.js b/exercises/robot-simulator/robot-simulator.spec.js
index d71af12324..2a46dcc534 100644
--- a/exercises/robot-simulator/robot-simulator.spec.js
+++ b/exercises/robot-simulator/robot-simulator.spec.js
@@ -1,4 +1,5 @@
 import Robot from './robot-simulator';
+import { InvalidInputError } from './robot-simulator';
 
 describe('Robot', () => {
   const robot = new Robot();
@@ -13,11 +14,8 @@ describe('Robot', () => {
   });
 
   xtest('invalid robot bearing', () => {
-    try {
-      robot.orient('crood');
-    } catch (exception) {
-      expect(exception).toEqual('Invalid Robot Bearing');
-    }
+    expect(InvalidInputError.prototype).toBeInstanceOf(Error);
+    expect(() => robot.orient('crood')).toThrow(InvalidInputError);
   });
 
   xtest('turn right from north', () => {