Some examples of DSM's custom capabilities in the optomechanics field are seen below.
Challenge: Provide a 3 axis positioning system that can be used in a vacuum environment.
Solution: When one of DSM's customers required a custom three-axis positioning system, DSM leveraged the flexure-based design of its flextensional piezo actuators to create independent X, Y, and Z stages. The resulting X and Y stages each provide 200 microns of travel, and the Z axis has a stroke of 500 microns. The original stage assembly was designed for vacuum compatibility and was provided with benchtop models of DSM's VF linear piezo amplifier. The basic design of the stage system is scalable to smaller/larger displacement capabilities. As a follow-on deliverable to the original, open-loop XYZ system above, DSM's customer requested closed-loop capability for the X and Y axes. DSM incorporated capacitive probes and used SA-100 linear servo amplifiers to provide stand-alone servo control. A 24-bit analog input accepts the position target signal, and digital I/O provides flags for "in-range" and data acquisition triggers.
To learn more about single-axis piezoelectric stages, like the ones used in this application to produce XY motion, check out the XSA-0200C product page. To learn more about piezo actuators like the one used to provide Z-axis motion, check out the array of standard offerings listed on our Piezo Actuators products page or contact us to discuss your application.
High Force Linear Actuation
Challenge: Researchers at NASA asked DSM to design and build a high force piezoelectric motor for macro positioning in extreme environments.
Solution: Using patented technology, DSM developed the I-90 step-and-repeat motor. Measuring just 63 mm x 57 mm x 18mm (2.5in x 2.3in x 0.7in), this compact motor is capable of generating an output force of 90N (20.2lb) with a total stroke of 25mm (0.98in) and speeds of up to 30mm/sec.
3-Axis Kinematic Mount
Challenge: Deliver a 3-axis optical mount for use under vacuum.
Solution: DSM used its experience in flexure mechanisms to design a backlash- and stiction-free 3-axis rotary mount capable of supporting a 4kg payload. The design requirements included +/- 2 mm of linear travel adjustment in one axis and +/-2° of rotational adjustment in two additional axes. DSM designed the flexure mount using a titanium and aluminum construction. Fine thread screw adjusters provide manual adjustment capability. Pre-load springs and flexure pivots provide return force. Special attention was paid to ensure the assembly's design minimizes undesirable motion during temperature transients and shock loading.
Challenge: Design and build a robotic goniometer to allow researchers at NIST to automate the data collection process needed to generate bidirectional reflectance distribution functions. The system’s design specification and acceptance testing procedure were developed to ensure that samples ranging from a less than an inch in diameter to over 12x12” square could be positioned and oriented with the accuracy required by an agency whose very name is synonymous with accuracy.
Solution: The Robotic Optical Scatter Instrument, better known as ROSI, was designed and constructed by DSM. The system uses a COTS precision 6DoF robot and a custom sample holder with integrated rotation stage to precisely position and orient optical samples with respect to an incident laser and detector. At the time of construction, ROSI represented the first robotic goniometer in the United States and one of only a handful of such systems in the world. ROSI will be officially presented to the optics community at the SPIE’s Optical Engineering +Applications conference in August of 2013.
Goniometry with Large Linear Excursion
Challenge: Design and build high-precision goniometer with closed-loop control of six independent degrees of freedom, including over 100ft of linear displacement, for use at the National Institute of Standards and Technology’s National Calibration Facility for Retroreflective Traffic Control Materials.
Solution: DSM designed and built at an automated goniometer capable of supporting samples weighing up to 10kg and measuring up to 125 cm in length. The system is capable of translating samples ± 30.5cm along the vertical axis while maintaining the samples position along orthogonal axis to within 0.005cm. DSM was able to accomplish this feat by using precision stages incorporated into a precision assembly, all mounted on 30m of precision railing.