Changed angular limits of articulation joints for the articulated crawler to match configurable joints setup in classical crawler.

UnitySDK/Assets/ML-Agents/Examples/Crawler/Prefabs/Body.prefab

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     target: 0
     targetVelocity: 0
   m_YDrive:
-    lowerLimit: -120
-    upperLimit: 120
+    lowerLimit: -20
+    upperLimit: 20
     stiffness: 0
     damping: 0
     forceLimit: 3.4028235e+38
-    lowerLimit: -120
-    upperLimit: 120
+    lowerLimit: -60
+    upperLimit: 0
     stiffness: 0
     damping: 0
     forceLimit: 3.4028235e+38
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   m_ComputeParentAnchor: 1
   m_SwingZ: 0
   m_Twist: 1
   m_XDrive:
-    lowerLimit: -120
-    upperLimit: 120
+    lowerLimit: -150
+    upperLimit: 0
     stiffness: 0
     damping: 0
     forceLimit: 3.4028235e+38
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   m_ComputeParentAnchor: 1
     target: 0
     targetVelocity: 0
   m_YDrive:
-    lowerLimit: -120
-    upperLimit: 120
+    lowerLimit: -20
+    upperLimit: 20
     stiffness: 0
     damping: 0
     forceLimit: 3.4028235e+38
-    lowerLimit: -120
-    upperLimit: 120
+    lowerLimit: -60
+    upperLimit: 0
     stiffness: 0
     damping: 0
     forceLimit: 3.4028235e+38
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-  m_ParentAnchorRotation: {x: 0, y: 0.38268346, z: 0, w: 0.9238795}
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+  m_ParentAnchorRotation: {x: 0, y: 0.38268352, z: 0, w: 0.9238796}
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   m_AnchorRotation: {x: 0, y: 0.38268346, z: 0, w: 0.9238795}
   m_ComputeParentAnchor: 1
   m_SwingZ: 0
   m_Twist: 1
   m_XDrive:
-    lowerLimit: -120
-    upperLimit: 120
+    lowerLimit: -150
+    upperLimit: 0
     stiffness: 0
     damping: 0
     forceLimit: 3.4028235e+38
   m_GameObject: {fileID: 3030804272900157282}
   m_Enabled: 1
   m_Mass: 3
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-  m_ParentAnchorRotation: {x: 0, y: -0.9238795, z: 0, w: -0.3826835}
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   m_ComputeParentAnchor: 1
     target: 0
     targetVelocity: 0
   m_YDrive:
-    lowerLimit: -120
-    upperLimit: 120
+    lowerLimit: -20
+    upperLimit: 20
     stiffness: 0
     damping: 0
     forceLimit: 3.4028235e+38
-    lowerLimit: -120
-    upperLimit: 120
+    lowerLimit: -60
+    upperLimit: 0
     stiffness: 0
     damping: 0
     forceLimit: 3.4028235e+38
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   m_AnchorRotation: {x: 0, y: 0.38268346, z: 0, w: 0.9238795}
   m_ComputeParentAnchor: 1
   m_SwingZ: 0
   m_Twist: 1
   m_XDrive:
-    lowerLimit: -120
-    upperLimit: 120
+    lowerLimit: -150
+    upperLimit: 0
     stiffness: 0
     damping: 0
     forceLimit: 3.4028235e+38
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   m_AnchorRotation: {x: 0, y: 0.38268346, z: 0, w: 0.9238795}
   m_ComputeParentAnchor: 1
   m_SwingZ: 0
   m_Twist: 1
   m_XDrive:
-    lowerLimit: -120
-    upperLimit: 120
+    lowerLimit: -150
+    upperLimit: 0
     stiffness: 0
     damping: 0
     forceLimit: 3.4028235e+38
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   m_Enabled: 1
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-  m_ParentAnchorRotation: {x: 0, y: 0.9238796, z: 0, w: -0.3826834}
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   m_ComputeParentAnchor: 1
     target: 0
     targetVelocity: 0
   m_YDrive:
-    lowerLimit: -120
-    upperLimit: 120
+    lowerLimit: -20
+    upperLimit: 20
     stiffness: 0
     damping: 0
     forceLimit: 3.4028235e+38
-    lowerLimit: -120
-    upperLimit: 120
+    lowerLimit: -60
+    upperLimit: 0
     stiffness: 0
     damping: 0
     forceLimit: 3.4028235e+38

UnitySDK/Assets/ML-Agents/Examples/Crawler/Scenes/ArticulatedCrawlerManualControl.unity

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UnitySDK/Assets/ML-Agents/Examples/Crawler/Scripts/ArticulatedCrawlerAgent.cs

         
         // For starting position, make a random orientation
         Quaternion rotation = Quaternion.identity;
-        rotation.SetLookRotation(Random.onUnitSphere * 10.0f + position, Vector3.up);
+        Vector3 randomViewPos = Random.onUnitSphere * 10.0f + position;
+        randomViewPos.y = position.y; // Look at the height of body center
+        
+        rotation.SetLookRotation(randomViewPos, Vector3.up);
         
         m_JdController.Reset();