Let's Get Mechanical

Even as alternatives have been developed, mechanical components remain as much a part of the motion profile as speed and accuracy.

"Advanced mechanical motion control components working in unison with today's electronic controls offer this performance at a cost-effective price point, which maximizes customer value," says David Hein, vice president of engineering, Nexen Group (www.nexengroup.com).

John Pieri, product line manager, Thomson (www.thomsonlinear.com), illustrates how the technology remains the best choice in certain applications. "One example is electromechanical wrap spring and friction clutches and brakes, which are widely used as an alternative to leading-edge servo technology," says Pieri. "Clutches and brakes offer flexible or custom mounting, simple installation, high accuracy, low power draw and high torque per unit size, all at an inexpensive cost compared to servo technology. Servo technology is overkill for most motion applications, in that the complexity and cost far exceed the requirement."

George Edwards, chief engineer, Fabco-Air (www.fabco-air.com), agrees that simplicity and cost are major attributes of mechanical motion. "Most machine element motions follow fairly simple paths," he explains. "Pneumatic actuators can provide these motions for low initial cost and follow with easy, low-cost maintenance and service as well. Pneumatic force outputs can meet most application requirements, ranging from a few ounces to several tons using force-multiplying air cylinders."

Installation, operation and maintenance are more easily accomplished with mechanical motion components, too, says Bob Jeter, applications engineer, Amacoli (www.amacoil.com). "Mechanical components require little to no training and are easy to install and operate," he explains. "Electronics can be complex and require expert technical support, while setup for mechanical devices is generally intuitive and they are easy to fix, thereby reducing downtime."