I wonder how practical living tissue as actuator for bio-robots. It needs to be fed, kept healthy and clear of infections, and replaced when beyond certain age.

I wonder how practical living tissue as actuator for bio-robots. It needs to be fed, kept healthy and clear of infections, and replaced when beyond certain age. I remember all those (temperature/pH/electro/magneto-sensitive) hydrogels actuator publications: Really cool experiments, but not really useful to engineer a replacement for electric motors.