Direct drive or Indirect? That’s the question
spotlight September 2020
Nobleo TEchnology has published an article in the well known Mikroniek, a magazine for precision engineers. What if it is possible to create an indirect-drive actuator with the benefits of a direct
drive? Typical struggles in actuator selection are to balance upsides, such as high force,
with the downsides of additional mass, volume and availability. Adding a transmission
has its own downsides, such as friction, backlash and hysteresis. But what if a gear ratio
can be created with the aid of flexure mechanics, eliminating all these downsides?
How does one deal with the parasitic movements, the own guiding stiffness, dynamics
and motor choice in a static use case? Here, a pragmatic implementation is presented
of an (in)direct-drive actuator that is self-guided and compliant in multiple passive
directions to be used in a steady-state multi-axis kinematically coupled system.
Stiffness is dominant and accelerations are low, putting the linear motor outside
its comfort zone of merely high-dynamic motion.