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In this paper, a tunable aperture driven by a single-phase piezoelectric motor is presented. The piezoelectric motor is composed of piezoelectric ceramic and carbon fiber layer. The influence of fiber orientation on the mechanical characteristics of the motor is analyzed by finite element method. The prototype of the aperture is manufactured and tested. The results show that the opening and closing durations of the aperture are 89 ms and 92.4 ms, respectively, for a rotation range of 90°, under a driving voltage of 150V. The minimum angular resolution can reach $4^{*}$10-5 radian.

This study aims to establish a system of employing design thinking in the K-12 education based on service design methodology. (1) Find a way to introduce design thinking in K-12; (2) Construct an education system inspired from service design for future practices. (3) Proposes as curriculum framework that puts design thinking as the key strategy with a series of real-life assessments. Service design’s methods and tools is used to identify the stakeholder’s characteristic and demands, figure out the target audience along with service objectives, sort out the relationships between them and establish a service process. Through teaching practice, this research studies and proposes a new alternative to employ design thinking in K12 education. Moreover, proposes a curriculum model centered on design thinking by combining the K12 preliminary courses with design workshops, research activities, etc. The new model is exemplified through practices in the real world’s teaching. The construction of the new educational framework based on service design methods will effectively promote the development of design thinking in the future K12 education.

Design thinking is a thinking tool, process, and method to guide creative activities. This paper makes a comparative research on STEAM education in America, phenomenon-based learning in Finnish, Design and Technology Course in England, and K-12 design thinking education in China by literature research and case study, and summarizes the current situation of design thinking education in K-12 around the world. This work aims to analyze the present difficulties and then propose the ways to promote K-12 design thinking education in China. We conclude that, as for K-12 design thinking education in China, some progress has been made in organizational form, project theme and activity process, but there are still many difficulties. To further promote K-12 design thinking education in China with a high quality, it is necessary to use service design methodology to coordinate all stakeholders and integrate the social resources.

Owing to characteristics of single-step fabrication and rapid prototyping, 3D printing have potential applications in processing piezoelectric motors with complex structures. In this paper, a 3D printed resin-based bimodal piezoelectric motor is proposed. Four slots of the motor are designed to reduce the influence of large damping caused by polymer’s viscoelastic and enhance mechanical properties. Considering the viscoelasticity and internal structure of the stator, a dynamic model based on the proposed motor is developed. Furthermore, parameters of these slots are optimized using the Taguchi method. Prototypes are fabricated and experimentally investigated. The results demonstrate that the first longitudinal mode and the second bending mode are 17 765 Hz and 18 006 Hz respectively, which are consistent with the analytical model results. Under the voltage of 300 Vpp, the maximum no-load speed and maximum driving load of the slotted motor are 200 r min−1 and 20 g with a speed of 6 r min−1, respectively. Compared with the motor without slots, the speed and load capacity are increased by 25% and 33%. Therefore, the motor with slots exhibits better mechanical output performance.