Here are a few ways to combine and refine those sentences:
**Option 1 (Focus on the systems’ evolution):**
“Training systems that allow robots to negotiate the real world are becoming increasingly sophisticated, largely thanks to the advanced virtual worlds where these robots are now being trained.”
**Option 2 (Emphasizing the virtual worlds as the sophisticated element):**
“The virtual worlds where robots are trained are evolving into increasingly sophisticated training systems, enabling them to better negotiate the complexities of the real world.”
**Option 3 (More concise):**
“The sophisticated training systems that enable robots to negotiate the real world are increasingly leveraging advanced virtual worlds for their development.”
All options clarify the relationship and reduce redundancy. Option 2 is probably the most direct fusion of your original sentences.
