From todays press release:

QBotix today unveiled the QBotix Tracking System™ (QTS), a comprehensive dual-axis tracking system that employs rugged, intelligent and mobile robots to dynamically operate solar power plants and maximize energy output.

The solar panels are installed on QBotix designed mounting systems that don't have any individual motors and are optimized for cost, strength, durability and installation simplicity. The robots travel on a track and adjust each mounting system to optimally face the sun in succession. Each robot replaces hundreds of individual motors and controllers found on conventional tracking systems. The embedded intelligence and data communication capabilities of each autonomous robot optimize power plant performance and enables detailed operational knowledge at an unprecedented level.

QTS is now available for commercial deployments.