Quality Vision International


Video and multisensor measuring systems are traditionally "vertical" systems, with optics and camera positioned to view a part fixtured below. Traditionally, the part is translated under the optics using an XY stage, and the optics move up and down to focus and make Z-axis measurements.

A compound XY stage is a common arrangement on many smaller measuring systems, particularly benchtop systems. Two elements of the stage are assembled as a unit, with each moving element being supported and guided by the other. Compound stages rely on careful design, manufacturing and assembly to maintain orthogonal movement and accurate positioning.

For larger measuring ranges, it is more practical to separate the X and Y axes into two independent motion assemblies. Typically the Y-axis stage supports the part, and the optics and camera move along the X-axis, as well as moving up and down in the Z-axis. The fixed bridge style of system separates the X and Y axis motions, making it possible to maintain the essential straightness and squareness of movement with a simpler and less costly mechanism.

A unique variation on the fixed bridge architecture is the QVI patented elevating bridge design which moves the optics and camera on a rising bridge. This arrangement provides exceptional squareness and rigidity in the X and Z axes, particularly when a large Z-axis measuring range is called for.

When the required measuring range is very large, and parts are large and heavy, it is more practical to stage the part in fixed position and move the optics and camera in three axes around the part. These moving bridge style machines enable easier loading and unloading of bulky parts, and eliminate the complex and costly mechanisms involved in accurately translating a large moving mass. By moving the imaging system around the stationary part, throughput is improved and accuracy is enhanced.

QVI offers more than twenty unique mechanical transport arrangements to suit a wide range of part and work-holding fixtures. We strive to offer the highest throughput and accuracy in the most practical and cost effective arrangement for each measurement application.