I might be wrong, but I expect robotics to come before Biology. At least robotics is much easier to verify, most humans can look at a robot and let you know if it is working correctly or not.

In what way is robotics a frontier research area? (What sub-fields are considered frontier?)

Improved robotics would improve biology. Fast cheap accurate flexible pipette-bot would help in many labs. Imagine if a postdoc could demonstrate and the arm could watch and repeat.

Interesting topic, considering how many humans are unable look at themselves and know if they're working correctly or not!