Precision Engineering embraces the commitment to determinism underlying the rigorous design, construction and metrology of mechatronic systems, instruments, and manufactured components.
This commitment to determinism is embodied by solutions that are quantifiable, measureable, predictable, and repeatable. These approaches comprise the formulation of error budgets, risk assessments, and statements of uncertainty.
Historical and current applications include fabrication of targets for high energy lasers, optics manufacturing, EUV lithography, assembly robots, surveillance systems, orbital telescopes, diamond turning, and measurement systems.
Kinematic Design: Exact constraint design provides reproducible micron-level alignment accuracy between remove-and-replace objects, like these vacuum chucks used for transferring laser target capsules. | |
Design for Manufacture: Successful design of hardware requires a knowledge of fabrication methods, the errors in fabricating and measuring components, and an understanding of how errors propagate or are combined during an assembly operation. | |
Micro Fabrication: As dimensions of fabricated components and assemblies become smaller, control of errors can become more difficult. For Micro-Fabrication, the error budgeting process and the fundamental sources of errors can vary from experiences gained at macroscopic dimensions. In addition, the use of microscopy and handling techniques for small fragile parts presents novel challenges for the fabrication engineer, machinist, or metrologists. As dimensions and tolerances shrink below the wavelength of light, standard machine vision methods for monitoring or handling operations must be replaced with advanced sensor systems. | |
Mechatronic Systems: Mechatronics, the synthesis of mechanics, electronics, system dynamics and controls, heat transfer, and fluid dynamics, is exemplified by the Precision Robotic Assembly Machine, which scales an operator's hand movements and touch into the world of microns and milligrams for assembling laser-driven fusion ignition targets. | |
Precision Fabrication & Metrology: An essential element in controlling errors in a system is to understand and minimize errors among the components and assemblies. Key to this is fabricating components, whether they are optical surfaces, bearing races, mounting surfaces, etc., that have errors that are within the error budget dictated by the application. For many applications, the size of these errors are below the capabilities of common fabrication machines, and require an intimate knowledge of material properties, the material removal (or addition) process, and the errors of the machine tool. Often, machine tools and processes that are not commercially available must be developed to meet program goals. In addition, metrology forms the link to characterizing the errors on the workpiece as well as within the machine tool mechanism used for generating the surface. | |
Opto‐Mechanical Systems: As a special application area of precision engineering, the system design and construction of opto-mechanical systems is illustrative of the process of meeting functional requirements, such as wavefront quality, by controlling the mechanical and dimensional tolerances on optical surfaces and the mounting hardware. An especially valuable tool in meeting optical requirements is a performance model that links mechanical properties and variables (surface figure, finish, alignment position, etc) with optical performance. This model will inform the engineer of the trade-offs among parameters and the sensitivity of performance with a given mechanical tolerance. |
John Taylor
Group Leader, Precision Systems and Manufacturing
Materials Engineering Division (MED)