Kinematic Mount Selection for Optical Scanning Assemblies
Kinematic mount selection for optical scanning assemblies isolates substrates from thermal and dynamic distortions while maintaining sub-microradian repeatability.
Brinelling Threshold
Meaning
Stress limits for bearing surfaces define the point at which permanent plastic deformation occurs under a static or shock load. Exceeding the brinelling threshold results in microscopic indentations that lead to increased friction and premature failure of the motion system. The value is typically expressed in megapascals or as a maximum static load rating provided by the bearing manufacturer.
Surface Integrity
Hardness of the raceways and rolling elements determines the resistance to localized yielding. A higher brinelling threshold allows for greater shock absorption during shipping or high acceleration maneuvers in the production cycle. Designers must distinguish between the capability of the material to resist surface marks and the total capacity of the assembly to carry a moving load.
Load Assessment
Static safety factors are applied to the peak anticipated force to prevent race damage. If a system undergoes a hard stop or collision, the impact force often exceeds the brinelling threshold even if the steady state load is low. This damage is detected by monitoring torque ripples or vibration signatures during a low speed sweep.
Operational Limit
Indentations on the bearing surface cause audible noise and non repeatable positioning errors. Once the metal is permanently deformed, the component must be replaced to restore precision. High volume manufacturing depends on staying well below this limit to ensure long term equipment uptime.