back-drivable linear motor?
back-drivable linear motor?
(OP)
Hey all,
I am looking for an electrical linear actuator... does this exist?
~4" stroke
~5pound force (less may be ok)
highly backdrivable, even when energized and commanded
low speed (1 inch per second would be ok)
I am looking for a response similar to what pneumatics would produce, minus the stiction of seals and noise and compressor...
Does anyone make long travel voice coil actuators?
the goal is a consumer product, but I am in prototyping, so cost is not the first concern here.
thanks for your thoughts
I am looking for an electrical linear actuator... does this exist?
~4" stroke
~5pound force (less may be ok)
highly backdrivable, even when energized and commanded
low speed (1 inch per second would be ok)
I am looking for a response similar to what pneumatics would produce, minus the stiction of seals and noise and compressor...
Does anyone make long travel voice coil actuators?
the goal is a consumer product, but I am in prototyping, so cost is not the first concern here.
thanks for your thoughts
RE: back-drivable linear motor?
https://www.marshbellofram.com/bellofram-pcd/types...
The problem with voice coils are that they use power constantly to maintain any force.
You could use a stepper motor with screw drive to compress a spring to the desired force. The controller would move the motor to maintain constant compression on the spring.
RE: back-drivable linear motor?
See if it may be scaled up, a lot.
Or
Low pressure hydraulics with position monitoring and low pressure relief valves to allow overcoming the commanded position.
Or
Simple and almost off the shelf:
A screw drive actuator with the load positioned by a pair of springs, so that any opposing force greater than your threshold will allow movement by compressing one or the other spring.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: back-drivable linear motor?
Waross, the spring-intermediaty on a leadscrew system: I had been mulling that, and it's cool to see it confirmed by another independant genesis! I am going to explore that further, as a plan B.
Is anyone familiar with the actuators that toyota uses for their powered lift gates? they are too noisy, but highly backdrivable, and they appear to have "stall" detection. any idea how they achieve this?
thanks again!
RE: back-drivable linear motor?
Keith Cress
kcress - http://www.flaminsystems.com
RE: back-drivable linear motor?
Or, three small hydraulic cylinders in a closed system. Two will be positioning forces and the third may be loaded by a torque motor to vary the pressure.
Bill
--------------------
"Why not the best?"
Jimmy Carter