20191106

DISTA=?; returns [" 200.0000\r"] DISTB=?; returns [" 200.0000\r"] DISTC=?; returns [" 200.0000\r"] FILTVAL=? returns [" 7.0000\r"] REQFILT=? returns [" 256.0000\r"]

SHOW FILTISIN involves show_$1 which translates to read_$1 then replaces $1 to FILTISIN which the low level command is read_FILTISIN then sends to dolowlevelcommand calls the read method

SPIE paper 2004 actuators use stepper motors with resolution 4800 steps per inch or 5.29 micron per step. ethernet based galil model 2180 eight axis motion controller the motion controller controls

• filer wheel rotation motor
• filter wheel translation motor
• focus actuators
• guide camera focus state
• guide camera filter wheel

lvdt - absolute linear position/displacement transducer. Converts a position or displacement from a mechanical reference into a proportional electrical signal. One containing phase(direction) and amplitude(distance)