All You Wanted To Know About Linear Stages and Their Uses

Linear Stages

Any object is said to be capable of rotating in 3 axes or translate along 3 axes. Thus an object is said to have freedom of movement in 6 degrees. Linear stage allows motion only in one direction.

The linear stages are devices used to control motion or movement of the object. Linear stage consists of a platform that moves along with a base. The platform and base are connected to each other by some form of a mechanism which helps in restricting motion or movement of the platform in one dimension or direction. Many different styles of guides are made in the market. Each guide has its pros and cons. Hence a guide may be more suitable in one application and may not be appropriate in other application.

These stages can also be called as translation stages or linear slides since they achieve the same purpose of motion control. A linear slide has almost similar functions to that of these stages.

A linear stage can be roughly classified in two categories such as manual and motorized stage. Motorized stages are further classified depending on the type of motor used etc.

Manual stage consists of a travel guide and driving structure. Many types of travel guides and related driving structures are available in the market. Today, users can get their stages custom made to their needs. For example, a stepper motor along with a knob can be used to operate a stage. In second option, a DC motor may also be used along with an encoder. Since DC motor does not move in fixed lengths, its movement needs to be reported to a controller which then further handles the motion.

How to Select a Stage for your Specific Requirements

Following factors should be considered while selecting a stage that suits your requirement.

• Accuracy
• Resolution
• Repeatability
• Load capacity
• Stiffness
• Environmental sensitivity
• Costs
• Errors allowed
• Protection on travel
• Locking mechanisms

Different bearings are available in the market each suitable for particular needs. Wide selection of quality linear slide is available. They have quality linear stage for micro positioning and nano positioning applications.

How to Build Multiple Axis Stages

If the need is to control positions in more than one direction, more than one linear stages can be used together. One stage can be mounted to the platform of the other stage so that they are in right angles to each other. If there is a need of bringing together three stages, then they should be attached to each other in orthogonal fashion. Sometimes they are integrated previously instead of assembling two or three single stages together. Moreover, four or five or six axis stages can also be manufactured. The linear rotary elements of these stages should be attached to each other in some fixed positions.

About the Author

PI is well known throughout the high-tech world as a leader in design and manufacture of motion control products, linear actuators, piezo ceramics and nanoactuators, hexapod 6DOF positioning systems, linear motor and micro robots.