Nymotion LLC

Made in the USA
Sales & Application Support:  503 617-0252

Linear Thrusters are a tried and proven mainstay in the pnuematic cylinder, shaft guided tooling plate positioning niche.  Nymotion offers both Step and Servo Precision Thrusters featuring Size 8, 11, 17 and 23 linear actuators.     

PST Series Thrusters are precision, shaft guided tooling plate slides.  The machined bearing body is designed for quick mounting to machine bases or structural extrusions and mounting features allow stacked, multiaxis  PST assemblies.  Stepper and Servo Thrusters use the identical non-captive linear actuator.

Inquiries for custom tooling plates for mounting optics, probes and grippers are welcome. 

• Integrated IP67 home sensor
• Size 8, 11, 17, 23 and 34 actuator frame sizes
• Open Loop Stepper w/ Speed and Position Mode Control
• Closed Loop Servo w/ Speed, Position and Torque Mode Control
• Anodized or Electro less Ni Housing and Tooling Plate
• Light weight ceramic or precision ground stainless shafts
• PST lead options range from 0.635 mm/rev to 25.4 mm/rev.  Contact Nymotion for further information.
• PST Thrusters are a derivative of time and market proven pneumatic cylinder, shaft guided thrusters. 
• Precision Step Thrusters provide:
• Micron and submicron positioning.
• High Accuracy with Outstanding Repeatability
• Precision Servo Thrusters provide:
• Micron and submicron positioning
• Quicker, quieter motion profiles with no resonance
• Dynamic position maintenence
• Torque mode control.  "Move element A into B, maintain 10 lbs force for 30 seconds ..."

• Greater repeatability.  +/- 1 to 5 microns (depending on lead and bearing selection.
• Programmable motion control.
• Long stroke Z (lift) applications.
• PST Tooling Plates have multiple threaded and c-bored mounting options with precision slip fit dowels.
• Custom mounting plates with Z axis mounts and turn-key drive/controller kits are available on request.
• Clean Room and Vacuum Versions

• Thruster Travel.  Standard strokes provided in the chart.  Vertical (lift) strokes can be 2 – 3 X longer.  Contact Nymotion for longer travel (stroke), sizing guidance, cantilevered loads and optional recirculating ball linear bearings.
• Prototype Guidance:  Whether or not you are planning to use a NYT Hybrid Servo drive, always order “servo ready” HaydonKerk linear actuators with installed and tested E8P-512 or E5-1250 encoders.  With open loop controls, encoded hybrid linear actuators allow position verification when testing worse case motion profiles.  If there are lost steps, performance or audible noise issues contact Nymotion for NYT hybrid servo guidance and testing.   
• PST Step and Servo Thrusters use identical bipolar, low inductance, hybrid linear actuators.
• PST Step Thrusters are driven with widely available microstepping drives and drive/controllers.  Encoder feedback is an option.  NYT Series microstepping drives are highlighted below.
• PST Servo Thrusters are driven with NYT Series Hybrid Servo drive/controllers.  Servo Thrusters require a reasonably high line count, single ended or differential rotary or linear encoders.   Recommended rotary encoders:  E8P-512 (2048 ppr) or E5-1250 (5000 ppr w/ Index).  In general, higher line counts yield better results. 
• Homing Techniques
• Recommended:  An optional NPN (PNP on request) prox sensor (home) is available.  This sensor is integrated into the PST housing and activates as the machined tooling plate is retracted under the sensor.  Homing is repeatable to +/- 5 μm. 
• NYT Series Microstepping Drive/Controllers feature home-on-a-hard-stop algorithms.  Using this technique, homing is repeatable to +/- 50 μm (or better).
• NYT Series Hybrid Servo Drive/Controllers have a more sensitive home-on-a-hard-stop algorithm.  Using this technique, homing is repeatable to +/- 30 μm (or better).  When combined with a move-to-encoder index routine, homing is repeatable to +/- 5 μm.
• Homing speeds impact repeatability.

Resolution Notes:  Given a 6.25 mm/rev (0.25 in/rev) Lead 

Open Loop Microstepping @ /16 provides 200 FS/REV * 16 MS/FS = 3200 μs/REV.  Therefore:  6.35 mm/rev / 3200 μs/FS ~ 0.002mm or 2 μm / μs
Closed Loop Servo w/ 2048 ppr:  6.35 mm/REV / 2048 ppr ~ 0.003 mm or 3 μm / encoder count
Closed Loop Servo w/ 5000 ppr:  6.35 mm/REV / 5000 ppr ~ 0.00127 mm or 1.27 μm / encoder count