Precision Positioning Hexapods

Precision positioning hexapods are used for point-and-hold or slow tracking operation where minimum incremental step size, repeatability, and/or accuracy are critical. The HX-P400 incorporates flexure end-joints and absolute linear encoders on each actuator to optimize repeatability and accuracy. The HX-P500 is vacuum-compatible and uses preloaded bearing end-joints to accommodate a relatively large range of motion. Both systems are designed for stiffness to achieve high resonant frequencies and fast settling times. Customization is commonly done to meet program-specific requirements.




  • Alignment of telescope optics
  • Testing of precision optical systems
  • Beam/laser pointing

Performance Characteristics

  HX-P400 HX-P500
Payload mass Up to 8000 kg

Up to 8000 kg

Dimensions1 1650 mm D x 720 mm H 2000 mm L x 2000 mm W x 810 mm H
Hexapod mass 625 kg 684 kg

Range of motion2

  HX-P400 HX-P500
X (lateral) ±20 mm ±100 mm
Y (longitudinal) ±20 mm ±100 mm
Z (vertical) ±15 mm ±85 mm
Roll ±1.2˚ ±7.0˚
Pitch ±1.2˚ ±7.0˚
Yaw ±0.5˚ ±5.2˚

Minimum incremental step size

  HX-P400 HX-P500
X (lateral) 1 μm 3 μm
Y (longitudinal) 1 μm 3 μm
Z (vertical) 1 μm 3 μm
Roll <1 μrad 1 μrad
Pitch <1 μrad 1 μrad
Yaw 1 μrad 1 μrad

Repeatability (bidirectional)3

  HX-P400 HX-P500
X (lateral) 10 μm 15 μm
Y (longitudinal) 10 μm 15 μm
Z (vertical) 3 μm 15 μm
Roll 3 μrad 3 μrad
Pitch 3 μrad 3 μrad
Yaw 10 μrad 15 μrad
  HX-P400 HX-P500
Actuation type Brushless motor-driven roller screw Brushless motor-driven roller screw
Sensor type Absolute linear encoder Rotary encoder
End-joint type Flexures Preloaded Bearings
Vacuum-compatibility w/ customization Yes
Heritage usage Rubin Observatory/Large Synoptic Survey Telescope (LSST) James Webb Space Telescope testing

1. Envelope dimensions and interfaces are typically customized to meet program-specific requirements

2. The ranges of motion of the six axes are interdependent. Listed values represent the maximum range with all other axes at their zero positions and the center of rotation at the center of the payload interface.

3. Unidirectional repeatability is typically 3X-5X smaller than bidirectional repeatability.