Research on the Construction of Robot Curriculum Module under the Background of New Engineering

Under the background of the construction of new engineering and the strategy of “making China 2025”, the society has also put forward new requirements for the personnel training of mechanical specialties. Therefore, combining the training goal of mechanical design, manufacturing and automation in Beijing (Beijing), it is necessary to cultivate new direction and cultivate new growth point for “old” mechanical specialty. And social and economic development has a very important significance.

Fingerprint-inspired surface texture for the enhanced tip pinch performance of a soft robotic hand in lubricated conditions

The core capabilities of soft grippers/soft robotic hands are grasping and manipulation.At present,most related research often improves the grasping and manipulation performance by structural design.When soft grippers rely on compressive force and friction to achieve grasping,the influence of the surface microstructure is also significant.Three types of fingerprint-inspired textures with relatively regular patterns were prepared on a silicone rubber surface via mold casting by imitating the three basic shapes of fingerprint patterns(i.e.,whorls,loops,and arches).Tribological experiments and tip pinch tests were performed using fingerprint-like silicone rubber films rubbing against glass in dry and lubricated conditions to examine their performance.In addition to the textured surface,a smooth silicone rubber surface was used as a control.The results indicated that the coefficient of friction(COF)of the smooth surface was much higher than that of films with fingerprint-like textures in dry and water-lubricated conditions.The surface with fingerprint-inspired textures achieved a higher COF in oil-lubricated conditions.Adding the fingerprint-like films to the soft robotic fingers improved the tip pinch gripping performance of the soft robotic hand in lubricated conditions.This study demonstrated that the surface texture design provided an effective method for regulating the grasping capability of humanoid robotic hands.

A Fully Self-Healing Piezoelectric Nanogenerator for Self-Powered Pressure Sensing Electronic Skin

As an important way of converting mechanical energy into electric energy,a piezoelectric nanogenerator(PENG)has been widely applied in energy harvesting as well as self-powered sensors in recent years.However,its robustness and durability are still severely challenged by frequent and inevitable mechanical impacts in real application environments.Herein,a fully selfhealing PENG(FS-PENG)as a self-powered pressure sensing electronic skin is reported.The self-healing piezoelectric composite and self-healing Ag NW electrode fabricated through mixing piezoelectric PZT particles and conductive Ag NWs into self-healing polydimethylsiloxane(H-PDMS)are assembled into the sandwich structure FS-PENG.The FS-PENG could not only effectively convert external stimulation into electrical signals with a linear response to the pressure but also retain the excellent self-healing and stable sensing property after multiple cycles of cutting and self-healing process.Moreover,a self-healing pressure sensor array composed of 9 FS-PENGs was attached on the back of the human hand to mimic the human skin,and accurate monitoring of the spatial position distribution and magnitude of the pressure was successfully realized.

Sliding friction of shale rock on dry quartz sand particles

The sliding friction of rock, involving all kinds of particles at the contact surface, is relevant to many problems, ranging from those in artificial engineering to earthquake dynamics. In this work, the frictional performance of the shale rock–dry quartz sand contact was investigated using a self-developed testing device. The study showed that the coefficient of friction of the contact increases with nominal stress and that the corresponding friction force increases approximately linearly with nominal stress, which is directly related to the contact stress between each single sand particle and rock shale. An overall dynamic coefficient, γ, reflecting the response of friction force to nominal stress, first decreases and then increases with area ratio, which is determined by not only the contact stress but also the interparticle friction force. These have important repercussions for a preliminary understanding of the frictional properties of the shale rock–dry quartz sand contact in hydraulic fracturing and related industrial applications.

Piezoelectric Peptide and Metabolite Materials

Piezoelectric materials are important for many physical and electronic devices.Although many piezoelectric ceramics exhibit good piezoelectricity,they often show poor compatibility with biological systems that limits their biomedical applications.Piezoelectric peptide and metabolite materials benefit from their intrinsic biocompatibility,degradability,and convenient biofunctionalization and are promising candidates for biological and medical applications.Herein,we provide an account of the recent progress of research works on piezoelectric peptide and metabolite materials.This review focuses on the growth mechanism of peptide and metabolite micro-and nanomaterials.The influence of self-assembly processes on their piezoelectricity is discussed.Peptide and metabolite materials demonstrate not only outstanding piezoelectric properties but also unique electronic,optical,and physical properties,enabling their applications in nanogenerators,sensors,and optical waveguiding devices.