Development of a Linear Motor Drive Testbed and Initial Thermal Behavior Results
Kari K. Harper, Bradley N. Damazo, M A. Donmez
The machine tool industry is moving toward using linear motors for both conventional and high speed machine tools due to many advantages: low maintenance, faster assembly times (compared with the more conventional ball screw drives), and improvements in both dynamics and accuracy. Linear motors are also used in ultra precise machine tools and coordinate measuring machines. On the other hand, lack of adequate invormation about the performance characteristics of such systems limits their widespread use. Therefore, as linear motors become more widely accepted, there is a need to develop measurement methods to characterize their performance. A linear motor testbed has been established within the Manufacturing Engineering Laboratory of the National Institute of Standards and Technology ( NIST) in support of this need. The testbed is used to investigate both measurement methods and key performance characteristics. For example, while the thermal characteristics of a linear motor are investigated, the influences of those thermal characteristics on the drive structure itself and thermal contributions to failure modes are also explored. Attention is given to determination of the most effective measurement methodologies for the overall performance of the drive.