try loc pos

Project/Assets/ML-Agents/Examples/Crawler/Scripts/CrawlerAgent.cs

 
         //Get position relative to hips in the context of our orientation cube's space
 //        sensor.AddObservation(orientationCube.transform.InverseTransformDirection(bp.rb.position - body.position));
-        sensor.AddObservation(bp.rb.position - body.position);
+//        sensor.AddObservation(bp.rb.position - body.position);
+            sensor.AddObservation(bp.rb.transform.localPosition);
         if (bp.rb.transform != body)
         {
             sensor.AddObservation(bp.rb.transform.localRotation);

Project/Assets/ML-Agents/Examples/Crawler/TFModels/CrawlerDynamic 1.nn.meta

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+    11400002: model data
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