ACS LP Mechanical-Bearing Direct-Drive Rotary Stage


Design Features

  • Integral pneumatic ER collet chuck
  • Clear aperture for product feed-through
  • Low inertia shaft for maximum acceleration
  • Integral rotary union
  • Ultra-low profile minimizes working height

Aerotech's ACS LP rotary stages with integrated ER collet chuck provide automated material handling capability for a wide range of materials and applications.

High Precision ER ColletACSLPAdv

The collet chuck on the ACS-100LP accepts an ER8 series collet, while the ACS-150LP uses an ER25 collet and the ACS-200LP uses an ER40 collet. These collets are readily available from machine tool component suppliers in sizes that support tube diameters from 0.5 mm to 30 mm. ER collets provide excellent run-out characteristics for applications requiring high-precision gripping of tubular material. The collet is retained with a threaded retaining cap that enables quick changeover, and is configured in a "fail-safe" normally-closed mode where full clamping force is applied when no air pressure is present.

Compact Package

The design of the ACS LP series direct-drive rotary stage was optimized to minimize stage height. The low profile of the stage reduces the effective working height of the system minimizing “stack-up” related errors.

Integral Rotary Union

Air is delivered to the collet or gripper assembly through an integral rotary union using a seal-less, frictionless design. This 100% noncontact rotary-union design ensures a lifetime of maintenance-free operation. The combination collet chuck and rotary union assembly also has significantly less friction and inertia than external assemblies created from discrete parts. This reduced inertia improves system performance by allowing higher peak acceleration and reducing position error during laser machining operations.

Brushless Direct-Drive

The ACS LP series utilizes direct-drive brushless motor technology to maximize positioning performance. Direct-drive technology is optimized for 24/7 production environments because there are no brushes to replace and no gear trains or belts to maintain. Direct drive also provides quicker acceleration and higher top speeds than gear or belt-driven mechanisms, which yields higher total overall throughput.

The low maintenance and high throughput characteristics of the ACS LP, coupled with the integral material handling capability, provide the lowest total cost of ownership when compared to component-level solutions.


ACS LP Series Specifications

Travel ±360° Continuous
Collet Option(1) ER8/MicroBore ER25 ER40
Aperture ER8/MicroBore 5 mm ER8, 0.9 MicroBore N/A N/A
ER25 N/A 16 mm N/A
ER40 N/A N/A 25 mm
Maximum Torque (Continuous) 0.64 N·m 2.36 N·m 5.99 N·m
Bus Voltage Up to 340 VDC
Max Speed(2) 1500 rpm 600 rpm 600 rpm
Accuracy(3) Uncalibrated 388 µrad (80 arc sec)
Calibrated 29.1 µrad (6 arc sec) 48.5 µrad (10 arc sec) 48.5 µrad (10 arc sec)
Repeatability(3) 14.6 µrad (3 arc sec) 19.4 µrad (4 arc sec) 19.4 µrad (4 arc sec)
Max Load(4) ER8/MicroBore 1.5 kg (Axial); 0.5 kg (Radial); 0.75 N·m (Moment)
ER25 10 kg (Axial); 5 kg (Radial); 6 N·m (Moment)
ER40 15 kg (Axial); 10 kg (Radial); 12 N·m (Moment)
Pin/Collet Runout(5) <25 µm
Tilt Error Motion 48.5 µrad (10 arc sec) 97 µrad (20 arc sec) 97 µrad (20 arc sec)
Inertia Unloaded 0.00038 kg·m2 0.00242 kg·m2 0.00843 kg·m2
Total Mass 2.0 kg 4.3 kg 7.6 kg
Finish Tabletop Hardcoat
Stage Black Anodize
  1. Collet chuck accepts Rego-Fix ER collets manufactured to DIN6499 specifications only.
  2. Maximum speed based on stage capability; maximum application velocity may be limited by system data rate, system resolution and load.
  3. Repeatability and accuracy are dependent on encoder resolution. To achieve the listed specifi cations, encoder resolution must be 0.36 arc sec or less.
  4. Maximum loads are mutually exclusive. Loading limits are due to the collet chuck mechanism. Contact Aerotech directly if part load requirement exceeds specifications.
  5. Measured TIR of precision gage pin chucked with an ultra-precision ER collet (DIN6499) 6 mm away from collet face with no load.
  6. Collet chuck mechanism is normally-closed. Collet mechanism requires air to open collet chuck. Air supply must be dry (0ºF dew point) oil-less air OR 99.99% pure nitrogen. Air or nitrogen must be filtered to 0.25 micron particle size or better.

ACS LP Maximum Speed for Encoder Option

-AS/-X5/-X10/-X25 1500 rpm 600 rpm 600 rpm
-X50 800 rpm 300 rpm 300 rpm


  • ACS-100LP
  • ACS-150LP
  • ACS-200LP

Ordering Information

Ordering Example

ACS -100LP -A -ER25 -AS -NS -WR -3.5MM

Ordering Options

Series Frame Size and Fixture TypeMotor TypeCollet TypeFeedback ConfigurationRear Shaft SealToolingCollet Sizes
ACS -100LP
-WR -1MM-5MM (ACS-100LP)
-1MM-15MM (ACS-150LP)
-16.5MM-25MM (ACS-200LP)

ACS LP Series Direct-Drive Rotary Stage

Option Description
ACS LP The ACS LP series direct-drive rotary stages have an integral single-port frictionless rotary union and can be configured with an ER collet.

Frame Size and Fixture Type

Option Description
-100LP 100 mm diameter, low profile, direct-drive rotary stage with ER8 collet closer, 0.64 N-m continuous torque, integral rotary union, and 300 mm (11.8 in) integral cables with HPD motor power and 25-pin D encoder feedback connectors
-150LP 150 mm diameter, low profile, direct-drive rotary stage with ER25 collet closer, 2.36 N-m continuous torque, and integral rotary union
-200LP 200 mm diameter, low profile, direct-drive rotary stage with ER40 collet closer, 5.99 N-m continuous torque, and integral rotary union

Motor Type (Required for ACS-xxxLP)

Option Description
-A Standard motor winding
-B Optional motor winding for ACS-150LP and ACS-200LP

Collet Type

Option Description
-ER25 Air actuated ER25 collet holder, normally closed; supports tube diameters from 1 mm to 16 mm; only available on ACS-150LP-XXX
-ER40 Air actuated ER40 collet holder, normally closed; supports tube diameters from 1mm to 30 mm; only available on ACS-200LP-XXX
-PRECISION Air actuated ER8 collet holder, normally closed; supports tube diameters from 0.5 mm to 5 mm; only available on ACS-100LP-XXX
-MICRO Air actuated MicroBore collet holder, normally closed; supports tube diameters from 0.2 m to 0.913 mm; only available on ACS-100LP-XXX

Feedback Configuration (Required)

Option Description
-AS Standard feedback device; 1 Vpp sine wave output; 3600 lines/rev on the ACS-100LP; 10,000 lines/rev on ACS-150LP/200LP; final resolution multiplier dependent
-X5 Square wave digital output; 18 arc sec resolution on ACS-100LP; 6.48 arc sec resolution on ACS-150LP/200LP
-X10 Square wave digital output; 9 arc sec resolution on ACS-100LP; 3.24 arc sec resolution on ACS-150LP/200LP
-X25 Square wave digital output; 3.6 arc sec resolution on ACS-100LP; 1.30 arc sec resolution on ACS-150LP/200LP
-X50 Square wave digital output; 1.8 arc sec resolution on ACS-100LP; 0.65 arc sec resolution on ACS-150LP/200LP
    Note: Digital output encoder signals are synthesized with a 16 MHz clock. Care must be taken to ensure that the encoder sample rate on the controller is at least 16 MHz or higher. Slower clock rates are available on request.

Rear Shaft Seal (Required for all ER based ACS; not valid for ACS-100LP)

Option Description
-NS No rear shaft seal
-S Rear shaft seal

ACS Tooling (Optional)

Option Description
-WR Spanner wrenches (2) for removing threaded collet retaining cap

Collet Sizes (Optional) – ACS-100LP

Option Description
-1MM ER8-1AA; ER-8 Collet, 0.70-1.00 mm ID
-1.5MM ER8-1-5AA; ER-8 Collet, 1.00-1.50 mm ID
-2MM ER8-2AA; ER-8 Collet, 1.50-2.00 mm ID
-2.5MM ER8-2-5AA; ER-8 Collet, 2.00-2.50 mm ID
-3MM ER8-3AA; ER-8 Collet, 2.50-3.00 mm ID
-3.5MM ER8-3-5AA; ER-8 Collet, 3.00-3.50 mm ID
-4MM ER8-4AA; ER-8 Collet, 3.50-4.00 mm ID
-4.5MM ER8-4-5AA; ER-8 Collet, 4.00-4.50 mm ID
-5MM ER8-5AA; ER-8 Collet, 4.50-5.00 mm ID

Collet Sizes (Optional) – ACS-150LP

Option Description
-1MM ER25-1AA; ER-25 Collet, 0.50-1.00 mm ID
-1.5MM ER25-1-5AA; ER-25 Collet, 1.00-1.50 mm ID
-2MM ER25-2AA; ER-25 Collet, 1.50-2.00 mm ID
-2.5MM ER25-2-5AA; ER-25 Collet, 2.00-2.50 mm ID
-3MM ER25-3AA; ER-25 Collet, 2.50-3.00 mm ID
-3.5MM ER25-3-5AA; ER-25 Collet, 3.00-3.50 mm ID
-4MM ER25-4AA; ER-25 Collet, 3.50-4.00 mm ID
-4.5MM ER25-4-5AA; ER-25 Collet, 4.00-4.50 mm ID
-5MM ER25-5AA; ER-25 Collet, 4.50-5.00 mm ID
-5.5MM ER25-5-5AA; ER-25 Collet, 5.00-5.50 mm ID
-6MM ER25-6AA; ER-25 Collet, 5.50-6.00 mm ID
-6.5MM ER25-6-5AA; ER-25 Collet, 6.00-6.50 mm ID
-7MM ER25-7AA; ER-25 Collet, 6.50-7.00 mm ID
-7.5MM ER25-7-5AA; ER-25 Collet, 7.00-7.50 mm ID
-8MM ER25-8AA; ER-25 Collet, 7.50-8.00 mm ID
-8.5MM ER25-8-5AA; ER-25 Collet, 8.00-8.50 mm ID
-9MM ER25-9AA; ER-25 Collet, 8.50-9.00 mm ID
-9.5MM ER25-9-5AA; ER-25 Collet, 9.00-9.50 mm ID
-10MM ER25-10AA; ER-25 Collet, 9.50-10.00 mm ID
-10.5MM ER25-10-5AA; ER-25 Collet, 10.00-10.50 mm ID
-11MM ER25-11AA; ER-25 Collet, 10.50-11.00 mm ID
-11.5MM ER25-11-5AA; ER-25 Collet, 11.00-11.50 mm ID
-12MM ER25-12AA; ER-25 Collet, 11.50-12.00 mm ID
-12.5MM ER25-12-5AA; ER-25 Collet, 12.00-12.50 mm ID
-13MM ER25-13AA; ER-25 Collet, 12.50-13.00 mm ID
-13.5MM ER25-13-5AA; ER-25 Collet, 13.00-13.50 mm ID
-14MM ER25-14AA; ER-25 Collet, 13.50-14.00 mm ID
-14.5MM ER25-14-5AA; ER-25 Collet, 14.00-14.50 mm ID
-15MM ER25-15AA; ER-25 Collet, 14.50-15.00 mm ID

Collet Sizes (Optional) – ACS-200LP

Option Description
-16.5MM ER40-16-5AA; ER-40 Collet, 15.50-16.50 mm ID
-17MM ER40-17AA; ER-40 Collet, 16.00-17.0 mm ID
-17.5MM ER40-17-5AA; ER-40 Collet, 16.50-17.50 mm ID
-18MM ER40-18AA; ER-40 Collet, 17.00-18.0 mm ID
-18.5MM ER40-18-5AA; ER-40 Collet, 17.50-18.50 mm ID
-19MM ER40-19AA; ER-40 Collet, 18.00-19.0 mm ID
-19.5MM ER40-19-5AA; ER-40 Collet, 18.50-19.50 mm ID
-20MM ER40-20AA; ER-40 Collet, 1916.00-20.0 mm ID
-20.5MM ER40-20-5AA; ER-40 Collet, 19.50-20.50 mm ID
-21MM ER40-21AA; ER-40 Collet, 20.00-21.0 mm ID
-21.5MM ER40-21-5AA; ER-40 Collet, 20.50-21.50 mm ID
-22MM ER40-22AA; ER-40 Collet, 21.00-22.0 mm ID
-22.5MM ER40-22-5AA; ER-40 Collet, 21.50-22.5 mm ID
-23MM ER40-23AA; ER-40 Collet, 22.00-23.0 mm ID
-23.5MM ER40-23-5AA; ER-40 Collet, 22.50-23.50 mm ID
-24MM ER40-24AA; ER-40 Collet, 23.00-24.0 mm ID
-24.5MM ER40-24-5AA; ER-40 Collet, 23.50-24.00 mm ID
-25MM ER40-25AA; ER-40 Collet, 24.00-25.0 mm ID