ADRS Mechanical-Bearing Direct-Drive Rotary Stage


Design Features

  • High torque output, direct-drive brushless servomotor
  • Cog-free slotless motor design for outstanding velocity stability
  • Direct coupled, high-accuracy rotary encoder
  • Ultra-low-profile minimizes working height

Aerotech's ADRS series with its direct-drive technology and low profile provide a superior alternative to belt- and worm-drive stages.

Compact Package

The design of the ADRS 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. In addition to the low overall height, the ADRS series provides a clear aperture that can be used for product feed-through or laser beam delivery.

Brushless Direct-Drive

To maximize positioning performance, the ADRS series utilizes direct-drive brushless motor technology. Direct-drive technology is optimized for 24/7 production environments as 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, yielding higher total overall throughput.

The low maintenance and high-throughput characteristics of the ADRS series provide a stage that yields the lowest total cost of ownership.

Slotless Motor

The ADRS series uses a slotless stator design that eliminates torque ripple. This motor technology provides ultra-smooth velocity stability comparable to a high-quality DC brush motor without all the DC motor’s inherent maintenance requirements. Since the slotless motor is directly coupled to the tabletop, velocity disturbances created by toothed belt drives or worm gears are eliminated.

Multiple Configurations

The ADRS series is available in 100 mm, 150 mm and 200 mm versions. Each stage has options for different motor windings to better match the stage to different operating conditions. The -B winding option provides the highest possible speed operation for a given available bus voltage, while the -A winding gives greater output torque for comparable current levels. Metric and “English” pattern tabletops are available and slotted mounting holes enable attachment to 25 mm and 1-inch hole pattern breadboards. The tabletop of the ADRS series has a labyrinth seal that protects the bearings and encoder from contamination. An optional shaft end-seal is available for applications where the bottom of the stage is exposed to contamination.


ADRS Series Specifications

ModelADRS-100 ADRS-150 ADRS-200
Tabletop Diameter 95 mm 140 mm 190 mm
Aperture 6 mm 15 mm 26 mm
Bus Voltage 340 VDC
Maximum Torque (Continuous) 0.48 N·m 2.36 N·m 5.99 N·m
Max Speed(1) 1500 rpm 600 rpm 600 rpm
Accuracy(2) Uncalibrated 388 µrad (80 arc sec)
Calibrated(3) 29.1 µrad (6 arc sec)
Repeatability(2) 14.6 µrad (3 arc sec)
Max Load(4) Axial 7 kg 20 kg 40 kg
Radial 3 kg 10 kg 20 kg
Axial Error Motion(5) 2 µm 5 µm 5 µm
Radial Error Motion(5) 3 µm 5 µm 5 µm
Tilt Error Motion 48.5 µrad (10 arc sec)
Inertia Unloaded 0.000038 kg-m2 0.00242 kg-m2 0.000843 kg-m2
Total Mass 2.0 kg 4.3 kg 7.6 kg
Finish Tabletop Hardcoat
Stage Black Anodize
  1. Maximum speed is based on stage capability. Actual speed may depend on encoder resolution, load, amplifier bus voltage and motor. See the S-series rotary motor for more information.
  2. Repeatability and accuracy are dependent on encoder resolution.  To achieve the listed specifications, encoder resolution must be 0.36 arc sec or less.
  3. With HALAR.
  4. Maximum loads are mutually exclusive.
  5. For the ADRS-100, error motion specifications are below 700 rpm. Above 700 rpm the max radial error is 5 microns. Errors measured 25 mm above the tabletop.

ADRS Maximum Speeds for Encoder Option

Encoder OptionADRS-100 ADRS-150 ADRS-200
-AS/-X5/-X10/-X25 1500 rpm 600 rpm 600 rpm
-X50 800 rpm 300 rpm 300 rpm
  • Axial and Radial Cantilevered Load Capability (ADRS100)
  • Axial and Radial Cantilevered Load Capability (ADRS200)


  • ADRS-100
  • ADRS-150
  • ADRS-200

Ordering Information

Ordering Example

ADRS -200 -M -A -AS -S

Ordering Options

Series Width (mm)Mounting PatternWinding Option Position Transducer Construction Options
ADRS -100

ADRS Series Direct-Drive Rotary Stage

Option Description
ADRS-100 100 mm wide direct-drive rotary stage with 0.64 N-m continuous torque output
ADRS-150 150 mm wide direct-drive rotary stage with 2.36 N-m continuous torque output
ADRS-200 200 mm wide direct-drive rotary stage with 5.99 N-m continuous torque output

Mounting Pattern

Option Description
-M Metric-dimension mounting pattern and holes
-U English-dimension mounting pattern and holes

Winding Options

Option Description
-A Low speed, high torque-constant winding option
-B High speed, low torque-constant winding option

Position Transducer

Option Description
-AS Standard feedback device; 1 Vpp sine wave output; 3600 lines/rev on the ADRS-100; 10,000 lines/rev on ADRS-150/200; final resolution multiplier dependent
-X5 Square wave digital output; 18 arc sec resolution on ADRS-100; 6.48 arc sec resolution on ADRS-150/200
-X10 Square wave digital output; 9 arc sec resolution on ADRS-100; 3.24 arc sec resolution on ADRS-150/200
-X25 Square wave digital output; 3.6 arc sec resolution on ADRS-100; 1.30 arc sec resolution on ADRS-150/200
-X50 Square wave digital output; 1.8 arc sec resolution on ADRS-100; 0.65 arc sec resolution on ADRS-150/200
    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.

Construction Options (ADRS-150 & -200)

Option Description
-S Bottom shaft seal (not available on ADRS-100; ADRS-100 has an integral bottom labyrinth seal)
-NS No bottom shaft seal