ZEISS XENOS Bridge-Type CMM Machines

Description

Innovative drive technology and the use of silicon-carbide ceramic also ensure outstanding dynamics. ZEISS XENOS is pioneering in its design, choice of material, drive technology and sensors.
The ZEISS XENOS was recently installed at NIST - making it NIST's largest ever CMM for their Big G (gravitational) measurement experiment.
Innovative mechanical design
ZEISS XENOS impresses with its new mechanical design based on the proven ZEISS CenterMax. Unlike the standard bridge-type design, the Y guideways are on top of the side walls which separate all moving axes from the clamping area. Because only the cross beam moves in the Y direction, there are lower moving masses. This remains constant at all times – a real benefit compared to a moving table. Together, the weight reduction and constantly moving masses enable optimal coordination of the drives regarding acceleration and maximum speed.

Linear drives in all axes
ZEISS XENOS uses linear drives on all axes. The benefits: high speeds, very fast acceleration, high positioning accuracy and shear force-free drives. In conjunction with the high resolution scales, the use of linear drives on ZEISS XENOS provide very high path adherence and extremely high positioning accuracy below 100 nanometers. For example, the stylus deflection remains more constant, which results in higher accuracy. Another benefit is evident when measuring curved surfaces: the more reliably and accurately a stylus follows the specified path, the more precisely errors can be determined.

Virtual central drive
XENOS from ZEISS features two linear drives in the Y direction, which are synchronized via a new technology developed by ZEISS: the central drive. It ensures optimal force distribution of the drives depending on the position of the X axis. This is enabled by the latest generation of controller and algorithm. It is a key element of maximum accuracy and the best possible path adherence throughout the measuring range.

Silicon-carbide ceramic
ZEISS XENOS uses an innovative silicon-carbide ceramic for the parts of the machine structure relevant to accuracy. Until now, this material has rarely been used for a comparable part size or accuracy. Compared to the standard aluminum-oxide ceramic, silicon-carbide ceramic exhibits around 50 percent lower thermal expansion, up to 30 percent higher rigidity and 20 percent less weight. Compared to steel, it delivers twice the rigidity at half the weight.

Enhanced VAST gold
ZEISS XENOS comes standard with the VAST gold reference probe from ZEISS. During development of ZEISS XENOS, this powerful sensor from ZEISS was further optimized for better accuracy and repeatability. The more rigid connection to the ram on ZEISS XENOS is also new. The VAST gold sensor is designed for styli up to 800 millimeters long and stylus weights up to 500 grams, including asymmetrical stylus configurations.

Optimized air bearings
New air bearings with an even more rigid connection enhance stability and and therefore enable better accuracy.

Improved electronics design
The influence on precision of moving cables on all coordinate measuring machines has been clearly reduced through the improved decoupling and a new electronics concept featuring decentralized modules. New Computer-Aided Accuracy (CAA) acceptance methods and additional CAA corrections are playing an increasingly vital role in achieving maximum accuracy.