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The product You were Looking for was moved Click Here for new Address Designs Single-Axis Tilt Platforms Single-Axis Tilt Platforms (θuX) can be designed in two ways: I. Single-Flexure, Single-Actuator Tilt Platform Examples: S-224 and S-226, see link The platform is supported by one flexure and pushed by one linear piezo actuator (see Fig. 1). The flexure determines the pivot point and doubles as a preload for the PZT actuator. The advantages of the single-flexure, single-actuator design are the straightforward construction and low costs. If angular stability over a wide temperature range is a critical issue, the differential piezo drive is recommended. II. Differential-Piezo-Drive Tilt Platform Examples: Custom designs. This design features two PZT linear actuators (operated in push/pull mode) supporting the platform (see Fig. 2). The case is machined from one solid metal block with FEA-designed (finite element analysis) wire-EDM-cut (electric discharge machining) flexures. The flexures provide for zero friction, zero stiction and excellent guiding accuracy. The differential design exhibits excellent angular stability over a wide temperature range. With this arrangement, temperature changes only affect the vertical position of the plat-form (piston motion) and have no influence on the angular position. When the operating- voltage is removed, the plat form returns to the center position. Several single and multi-axis designs are available. Multi-Axis Tilt Platforms PI offers two versions of multi-axis tilt platforms: I. Triple-Piezo-Drive Tip/Tilt Platform Examples: S-315 and S-316, see link The platform is supported by three piezo actuators spaced at 120° intervals. Because expansion of an individual PZT actuator affects both θuX and θuY rotation, external coordinate transformation (software or hardware) is required to allow platform position commands in θuX and θuY coordinates. See the equations and Fig. 3 for details. The triple-piezo-drive has another advantage. In addition to tilt motion, it allows active vertical control (piston motion) of the platform - an important feature for interferometric applications and correction of path length errors. Also, the design allows for a central clear aperture, ideal for transmitted-light applications. Like the differential drives, the triple-piezo-actuator design exhibits excellent angular stability over a wide temperature range. With this arrangement temperature changes only affect the vertical position of the platform (piston motion) and have no influence on the angular position. II. Differential-Piezo-Drive Tip/Tilt Platform Examples: S-330 and S-340, see link, see link. The platform is supported by four piezo actuators (two pairs) spaced at 90° intervals. Each actuator pair is operated as a unit in push/pull mode. The differential design exhibits excellent angular stability over a wide temperature range. Here too, temperature changes only affect the vertical position of the platform (piston motion) and have no influence on the angular position. After the operating voltage is removed, the platform returns to the center position. Fig. 1. Single-flexure, single-piezo actuator tilt platform design Fig. 2. Design of a differential-piezo-drive tilt platform Fig. 3. Triple-Piezo-Drive: A, B, C is the linear displacement of the corresponding piezo actuator. a = [2A - (B+C)] / 2a b = (B-C) / b z = (A+B+C) / 3 Example: S-315 Tip/Tilt Platform (see link). Æ = 13.9 mm a = 10.4 mm b = 12.0 mm A, B, C 0 to 12 μm