INTELLIGENT PRECISION CONTROL IN CNC GRINDING

The development of intelligent control techniques provides powerful means for the control of machine tools. In this paper, a intelligent control technique and an algorithm for precision control of CNC grinding of ceramic chips are introduced. In the process of ceramic chip CNC grinding, the dimension of the chips tends to get larger and the dimensional error to exceed the tolerance as the number of the chips increases which are machined on the same part program. There are many factors leading to the occurrence of the error and the law of error variation is very complicated. With the introduced intelligent self learning error compensation technique, the CNC system can improve the control strategy to compensate the error automatically. The simulational result is also given.

60 GHz SIW Steerable Antenna Array in LTCC

In this paper, we present a 60 GHz substrate-integrated waveguide fed-steerable low-temperature cofired ceramics array. The antenna is suitable for transmitting and receiving on the 60 GHz wireless personal area network frequency band. The wireless system can be used for HDTV, high-data-rate networking up to 4.5 GBit/s, security and surveillance, and similar applications.

Ceramic thermal wind sensor based on advanced direct chip attaching package

An advanced direct chip attaching packaged two-dimensional ceramic thermal wind sensor is studied. The thermal wind sensor chip is fabricated by metal lift-off processes on the ceramic substrate. An advanced direct chip attaching （DCA） packaging is adopted and this new packaged method simplifies the processes of packaging further. Simulations of the advanced DCA packaged sensor based on computational fluid dynamics （CFD） model show the sensor can detect wind speed and direction effectively. The wind tunnel testing results show the advanced DCA packaged sensor can detect the wind direction from 0° to 360° and wind speed from 0 to 20 m/s with the error less than 0.5 m/s. The nonlinear fitting based least square method in Matlab is used to analyze the performance of the sensor.

Fabrication of a hydroxyapatite-PDMS microfluidic chip for bone-related cell culture and drug screening

Bone is an important part of the human body structure and plays a vital role in human health.A microfluidic chip that can simulate the structure and function of bone will provide a platform for bone-related biomedical research.Hydroxyapatite(HA),a bioactive ceramic material,has a similar structure and composition to bone mineralization products.In this study,we used HA as a microfluidic chip component to provide a highly bionic bone environment.HA substrates with different microchannel structures were printed by using ceramic stereolithography(SLA)technology,and the minimum trench width was 50μm.The HA substrate with microchannels was sealed by a thin polydimethylsiloxane(PDMS)layer to make a HA-PDMS microfluidic chip.Cell culture experiments demonstrated that compared with PDMS,HA was more conducive to the proliferation and osteogenic differentiation of the human foetal osteoblast cell line(hFOB).In addition,the concentration gradient of the model drug doxorubicin hydrochloride(DOX)was successfully generated on a Christmas tree structure HA-PDMS chip,and the half maximal inhibitory concentration(IC50)of DOX was determined.The findings of this study indicate that the HA-PDMS microfluidic chip has great potential in the field of high-throughput bonerelated drug screening and bone-related research.