The PlanarHD air-bearing stage has been designed to maximize throughput. The design utilizes a highly-engineered mechanical structure that increases air-bearing stiffness and decreases moving mass.
Recent engineering advancements in motion control focus on the need to reduce costs and increase productivity.
Recent engineering advancements in motion control focus on the need to reduce costs and increase productivity. This issue has become increasingly important as engineering and assembly teams are required to accomplish more with fewer resources.
According to Al Ciez, division manager of the positioning systems division at Aerotech, the most significant benefit in recent advances in linear slides and stages has come in the cost of ownership.
“While the equipment costs have modestly increased, machine throughput has improved tremendously,” Ciez says. “Direct and indirect manufacturing costs can be dramatically reduced [resulting in] less operator time on fewer machines and less floor space required in a cleanroom.”
ADVERTISEMENT
Today’s Marketplace
Currently, the industry features a number of innovative linear slides and stages dependent upon the particular application requirements.
According to Nigel S. Watson, P.E., an engineering manager with Bishop-Wisecarver, an application requiring long strokes would benefit from a new design from Bishop-Wisecarver’s LoPro linear actuators. The LoPro actuators can accomodate virtually unlimited length, and have been regularly fabricated up to 80 feet.
The LoPro can simplify the design of gantry applications as the result of four new configurations that are belt, chain, lead-screw and ball-screw driven.
Aerotech’s VascuLathe and PlanarHD illustrate similar innovation, particularly in laser micromachining of small cylindrical parts.
The VascuLathe is an r-theta system that is highly optimized for laser micromachining, combining dynamic performance and ease of use.
The VascuLathe can produce benchmark parts up to four times faster than any previous generation product while improving part quality by up to 30 percent. “The mechanical design is optimized for this specific application and for the best achievable contouring performance,” says Aerotech's Ciez.
“To maximize the performance, advanced control system algorithms and trajectory generation techniques are used as part of the overall motion system. The mechanical design also integrates workholding features, eliminating the need for additional fixturing by the customer.
“This feature allows us as a manufacturer to control the moving masses, inertias and stiffnesses of, basically, all parts of the machine; and provide a 100 percent optimized solution,” Ciez adds.
The PlanarHD is an XY air-bearing stage. Air-bearing technology has been commercially available for over 40 years and many companies have offered planar-style designs for the last 10 years, but the new stage is unique in several dynamic performance areas.
“Geometrically, the dynamic straightness and flatness are improved by 50 percent by using CFD analysis techniques to optimize the air-bearing design,” Ciez says. The PlanarHD has made 5 g acceleration and 2 m/s speeds more achievable.
Advancements have also happened in material performance, specifically plastics, which are used more in slides and stages. Plastics, such as the Herculane wheels in HepcoMotion’s PDU2 actuator or polymer-overmolded stainless steel such as the integral wheels used in UtiliTrak, have properties that provide exceptional life, smooth travel and corrosion resistance at relatively low cost.
In Five Years Time
Stage performance advances will undoubtedly continue. Many opportunities still exist in motion system performance and throughput enhancement and companies with high-level systems engineering capability will be the leaders in these advances.
“Organizations with a limited engineering skill set, manufacturing capability and product offering will be hard-pressed to match the technical advances of companies that have a comprehensive engineering team and product line,” adds Ciez.
“Manufacturers will continue to engineer products that address customers’ needs to optimize resources and minimize costs,” states Watson. “Linear slides and stages will become more seamlessly integrated with motor technology, providing the capability of real-time synchronous feedback to users.
“There will always be a need and the advancement in materials and linear motor technology has created new markets for the industry as a whole.”