To improve the speed and control of rotary actuators used in laser scanning and other optical systems, engineers at Pangolin Laser Systems, Orlando, Fla., decided to take matters into their own hands and designed a new rotary actuator. The result, the VRAD-1510 is reportedly capable of higher speeds, greater range of rotation, faster responses, and more-precise shaft movement than other actuators. The low-power unit, which is based on an innovative dual-coil, segmented stator design, also costs about one-third less than existing rotary actuators. This means the device could be used in a range of electromechanical applications, including mechanical and automotive systems, robotics, HVAC, and valve control.
Pangolin designers developed a new and inexpensive way to make segmented stators without air gaps, which interfere with the motor’s magnetic field. The design also uses two, separately accessible coils, resulting in a compact, quiet, and durable actuator.
For durability, the actuator uses a magnetic spring and preloaded ball bearings. The unit also does not need mechanical stops on shaft rotation, which eliminates much of the noise, wear, and vibration. The shaft rotates more than ±60° from the neutral position. The actuator also has front and rear shafts, letting users add an encoder or position sensor for closed-loop operations, or other optional attachments.
The VRAD-1510 features a linear response. So applying twice the voltage gives twice the output angle; applying three times the voltage results in three times the output angle.
The actuator’s coils can be driven in series, in parallel, or separately, which makes the device flexible in terms of how it can be used. For example, instead of using both coils to generate torque, one can be used for dynamic braking or to sense velocity.
Units can be configured to meet customers specs in terms of torque factor, magnetic-spring stiffness, coil resistance and inductance, shaft diameter and length, bearing preload, and operating temperature range. The rectangular shaped unit measures 1.5 × 1.0 × 1.5 in.
© 2012 Penton Media, Inc.
