Two-Axis Linear Stage Simulates Earthquakes

Scientists, with the goal of safer buildings and saving lives, are testing building materials and structural designs in simulations of many recent earthquakes that have seismic data available. Using a two-axis high force linear positioning stage from H2W Technologies, they can simulate the effects of earthquakes as large as the largest recorded earthquake in history, the 9.5 magnitude quake on the open-ended Richter scale, in May of 1960 in Chile.

The standard high speed, high acceleration linear positioning stage's stroke is 8 in. in both the X and Y axes, while the force in the X axis is 400 lbs continuous (1200 lb peak) and the force in the Y axis is 200 lbs continuous (600 lb peak), although longer strokes and higher forces are available. The 3-phase brushless motors with Hall Effects and guided by ball linear bearings can produce the force and acceleration necessary to simulate different types of earthquakes, including a "Transform plate boundaries" quake, which is the most common destructive type of earthquake. This type of earthquake occurs when tectonic plates slide horizontally against each other, and at these boundaries destructive earthquakes can occur.

To accurately simulate the destructive forces of an earthquake in the laboratory, high acceleration and precise linear positioning are required. One micron resolution linear encoders provide positional accuracies to ± 20 µm and repeatability is better than ± 5µm. This high accuracy, high force XY stage is also suitable for pick-and-place applications involving heavy payloads and robotics. Stages with greater travels and custom mounting configurations as well as complete motion control systems (including electronics) can be provided.

H2W Technologies, Inc. is dedicated to the design and manufacture of linear and rotary motion products that are used in the motion control industry. The complete line of linear electric motors includes: Single and dual axis linear steppers, DC brush and brushless linear motors, voice coil actuators, and AC induction motors. Also offered is a complete line of ball screw, lead screw and belt driven positioning stages. Other motion control products include: Limited angle torque motors for compact, limited angular excursion rotary servo applications, 3 phase brushless rotary servo motors with matching digital servo amplifiers and permanent magnet linear brakes for fail-safe, zero power braking for baggage handling and people moving applications as well as amusement park rides.