This paper presents a novel Expressive Facial Control (ExFace) method based on Diffusion Transformers, which achieves precise mapping from human facial blendshapes to bionic robot motor control. By incorporating an innovative model bootstrap training strategy, our approach not only generates high-quality facial expressions but also significantly improves accuracy and smoothness. Experimental results demonstrate that the proposed method outperforms previous methods in terms of accuracy, frames per second (FPS), and response time. Furthermore, we develop the ExFace dataset driven by human facial data. ExFace shows excellent real-time performance and natural expression rendering in applications such as robot performances and human-robot interactions, offering a new solution for bionic robot interaction.

This paper discusses the implementation of impedance control method to a pair of backdrivable actuators for compliant walking of bipedal robot. The ability of simulating various stiffness of the mechanical joints is validated with experimental measurement. The experiment further shows promising results that the impedance control is able to reduce the ground impact force to protect the hardware.

Axial-flux permanent magnet synchronous motor (AFPMSM) is a promising solution for in-wheel direct-drive electric bikes (e-bikes) due to its disc-type topology, structural compactness, and high torque density. However, the large electric loading of conventional AFPMSMs for high torque output can lead to severe thermal rise and potential fault risk, which is unbearable for long-running operation and security requirement in e-bike scenario. To address this issue, a comparative study is conducted on the performance of AFPMSM with conventional surface-mounted PM array (S-AFPMSM) and Halbach PM array (H-AFPMSM). The design and optimization procedure for both AFPMSMs is conducted. The investigation result shows that S-AFPMSM features over 30% higher torque density than that of a radial-flux PMSM, but the thermal raise is too much for air-cooling condition. By utilizing Halbach PM array with self-shielding magnetization effect, H-AFPMSM has higher magnetic loading and much less heat loading when it outputs the same torque density as that of S-AFPMSM. As a result, the copper loss is reduced by over 30%, and accordingly the efficiency increases to 94%. A prototype of the motor is manufactured and tested, with results that agree well with the theoretical analysis.