Moderators: rjlittlefield, ChrisR, Chris S., Pau
The motor will be driven as follows (in the vertical setup with the THK KR 2001):How will you drive the motor?
What kind of the design tradeoffs do you mean?Higher torque usually means more drive power required, and often can mean less accuracy in microstepping due to the design tradeoffs
What you'll notice when physically examining various motors of different torque ratings is that the high torque ones generally have high starting torque, ie it's more difficult to move them by hand with no drive or load. I have a couple NEMA-23 motors which I can't move with my fingers! This is due to a much higher permanent magnet component in the rotor, which helps to "amplify" the effect of the applied currents, but also makes it tougher to overcome the natural "step" nature of the motor. It is the reason that the 5-phase motors are less "accurate" under microstepping than the 2-phase in that Lin paper. The 5-phase were designed for full-stepping, and it's easy to tell this when you rotate them by hand.Adalbert wrote: What kind of the design tradeoffs do you mean?
BTW, if you use a stepper with the low torque some steps can be over jumped, can’t it?
BR, ADi
ADi...I've often recommended folks stack"down", but there are arguments for both directions.Adalbert wrote:Hello Ray,Sometimes I use the CANON EF 70-200L as a tube lens.One problem you may have with a low-torque motor is unique to vertical systems...slippage.
In this case over 3kg / 7lb must be moved.
BTW, how to stack vertically DOWN or UP ?
BR, ADi
Sure, with a microscope I prefer to to stack upwards to prevent the damping grease retaining a bit the movement (at least with some old lazy models, if working perfectly it's the same) but you have more risk of crushing the subject against the objective, again only in some cases.ray_parkhurst wrote:ADi...I've often recommended folks stack"down", but there are arguments for both directions.
