Modeling and Optimization for a New Compliant 2-dof Stage for Locating Biomaterial Samples by an Efficient Approach of a Kinetostatic Analysis-Based Method and Neural Network Algorithm

Abstract

The nanoindentation technique is employed to characterize the behaviors of biomaterials. Nevertheless, there is a lack of development of a miniaturized precise positioner for in situ nanoindentation. Besides, modeling behaviors of the positioner are restricted due to its complex kinematic characteristics. Therefore, this paper proposes a novel compliant two degrees of freedom (dof) stage for positioning a biomaterial sample in in situ nanoindentation. In addition, a new modeling and dimensional optimization synthesis method of the stage is developed. The proposed effective methodology is developed based on a kinetostatic analysis-based calculation method, the Lagrange approach, and a neural network algorithm. With an increased advance in artificial intelligence, a neural network algorithm is proposed to extend the applicability of artificial neural networks in optimizing the parameters of the stage. First, the 2-dof stage is built via a combination of an eight-lever displacement amplifier and a symmetric parallelogram mechanism. Second, a chain of mathematical equations of the 2-dof stage is constructed using a kinetostatic analysis-based method to calculate the ratio of displacement amplification and the input stiffness of the 2-dof stage. Then, the Lagrange method is utilized to formulate the dynamic equation of the 2-dof stage. Finally, a neural network algorithm is adopted to maximize the natural first frequency of the proposed stage. The optimal results determined that the frequency of the stage can achieve a high value of 112.0995 Hz. Besides, the formed mathematical models were relatively precise by comprising the simulation verifications.

The Development of a 3D-Printed Compliant System for the Orientation of Payloads on Small Satellites: Material Characterization and Finite Element Analysis of 3D-Printed Polyetherketoneketone (PEKK)

“…where m S,A is the apparent mass of the specimen in the air, m S,IL is the apparent mass of the specimen in the liquid, and ρ IL is the water density at 23 • C, which is 0.998 g/cm 3 according to the supplier of the kit. The DSC is performed on a TA INSTRUMENT Q100 on a 7 mg PE Analysis was completed under nitrogen from 30 °C to 400 °C at a heating rat kept 3 min, and then cooled from 400 °C to 30 °C at 10 °C/min.…”

“…In Figure 11, the density of specimens printed "flat" is 1.07 ± 0.02 g/cm 3 and 1.15 ± 0.01 g/cm 3 for those printed "on edge". This 9% difference could be another explanation for the enhancement of "on edge" mechanical properties.…”

“…Compliant mechanisms are monolithic systems that produce complex movements through the elastic deformation of their structure. They have many applications, but they are mostly used in the medical [1], space [2], and precision domains [3,4]. Compliant mechanisms do not have backlash or wear, which leads to precise motions and absence of lubrication.…”

Modeling of a Nonlinear Coupled Compliant Mechanism via Developed Kinematics-integrated Neural Network Algorithm

“…1) White-box: the convolutional modeling method is based on compliance matrix theory, which is linear and not accurate. Despite the inaccuracy of the theoretical model, it can describe the trend between inputs and outputs Lyu and Xu (2023); Dang et al (2022b); Yong and Lu (2008).…”