Accurate Measurement of Micromachining Forces in Three Dimensions

微机械加工已越来越多地用于制造高科技的微型和微型设备，这些设备由各种材料制成，具有多种用途。实现微加工过程的质量和生产率的重大进步是将微加工转变为工业上可行的工艺的关键。因此，迫切需要有关过程和系统特性的基础知识。由于微加工力体现和显示了微加工过程和系统的力学、动力学、稳定性和健康状况的关键信息，因此精确测量这些力对于获得对微加工科学和工程的基本理解至关重要，从而实现微加工科学和工程的变革性进步。最先进的力测量系统无法准确测量微加工力，从而阻碍了进一步的发展。该奖项支持三维微加工力精确测量的科学和技术研究。该研究将创造一种独特的动态建模方法，为下一代测力计的设计提供信息。它们将极大地促进在许多领域制造无数微型和微型设备的能力的进步，包括医疗/生物医学、航空航天、军事/国防和消费产品。本课题的研究目标是：(1)了解结构动力学与测功机测力特性之间的关系；(2)创造补偿方法，显著扩大三维测量带宽；(3)构建/验证模型，以实现未来的测功机设计。为了实现目标1，将在商用微型加工测功机上进行实验模态分析。动态激励将使用定制的冲击激励系统提供，动态响应将使用激光多普勒振动仪测量。将收集（来自冲击系统的）激励和来自测功机的力并进行比较。不同的边界条件（固体，弹性）将被考虑。从这些测试中，将获得0-60 kHz带宽范围内的接收和力对力频率响应函数。为了实现目标2，反滤波技术将用于设计一种补偿方法，将测量带宽扩展至少20倍。将对所开发的补偿方法进行实验验证和功能评估（使用微铣和微钻工艺）。对于目标3，将使用谱-切比切夫技术建立测力机结构的结构动力学模型，包括不同的边界条件和工件动力学。这些模型也将使用与实现目标1相同的实验模态分析技术进行实验验证。

Micromachining has been increasingly used to manufacture high-tech micro- and miniature-scale devices from a variety of materials for many applications. Realizing significant advances in the quality and productivity of micromachining processes is vital to transform micromachining into an industrially-viable process. Thus, fundamental knowledge on process and system characteristics are urgently needed. Since micromachining forces embody and manifest critical information on the mechanics, dynamics, stability, and health of the micromachining processes and systems, accurate measurement of those forces is paramount to gaining fundamental understanding on, and thus, to realize transformative advances in, micromachining science and engineering. The state-of-the-art force measurement systems are incapable of measuring micromachining forces accurately, thereby hindering further advancements. This award supports scientific and technological investigations on accurate measurement of three-dimensional micromachining forces. The research will create a unique dynamic modeling approach to inform next-generation dynamometer designs. They will facilitate tremendous advances in the capability to manufacture a myriad of micro- and miniature-scale devices for many fields, including medical/biomedical, aerospace, military/defense, and consumer products.The research objectives of this project are (1) to understand the relationship between structural dynamics and force measurement characteristics of dynamometers; (2) to create compensation approaches to significantly expand three-dimensional measurement bandwidth; and (3) to construct/validate models to enable future dynamometer designs. To achieve Objective 1, experimental modal analyses will be conducted on commercial miniature machining dynamometers. The dynamic excitation will be provided using a custom impact excitation system, and the dynamic response will be measured using laser Doppler vibrometery. Both the excitation (from the impact system) and the forces from the dynamometer will be collected and compared. Different boundary conditions (solid, elastic) will be considered. From these tests, both the receptance and force-to-force frequency response functions will be obtained within the 0-60 kHz bandwidth. Towards Objective 2, inverse-filtering techniques will be used to devise a compensation approach to expand the measurement bandwidth by at least 20 folds. Both experimental validation and functional evaluation (using micromilling and microdrilling processes) of the developed compensation approach will be performed. For Objective 3, structural-dynamics models of the dynamometer structure, including different boundary conditions and workpiece dynamics, will be developed using the spectral-Tchebychev technique. These models will also be experimentally validated using the same experimental modal analysis techniques as those for achieving Objective 1.