Recent development of 3D printing technologies would provide the variety of electronic devices including environmental sensors and bio-applications. Polymer-based sensors are compatible with human-body parts or prostheses to monitor the body status of surfaces or surroundings such as temperature, humidity, and pressure. Conventional 1D or 2D fabrication processes are effective for mass production. However, specific shapes such as curvy or 3D pathways would require the 3D printed sensors to expand the possible applications.
In this study, organic temperature sensors fabricated on 3D printed surfaces are investigated to improve the device properties. 3D structures were fabricated using a DLP (direct light processing) 3D printer with photo-polymers. Sensor electrodes based on conductive carbon materials were printed on 3D shape structures. The resistances of organic temperature sensors were measured by the temperature variations. As the environmental temperature increased from 29 to 54℃, the resistance was decreased from 8.57 to 8.23 kΩ with the certain linearity, respectively. To further improvements, polymer composites comprising the inorganic nanoparticles were introduced to control the interfacial properties and the conductivity of composite carbons were improved.
Perpendicularity measurement is very important in machine assembly and calibration. Axis perpendicularity error often
contributes much more to the total error than the linear positioning and straightness errors. This paper presents two new
non-contact methods for measuring axis perpendicularity using vision system. In general a perpendicular master and a
dial gauge are used to measure the axis perpendicularity. We can obtain the axis perpendicularity by measuring
differences from the master. Therefore, its accuracy depends on the accuracy of perpendicular master. The accuracy of
the perpendicular master is therefore extremely important and it is impossible that the accuracy of a perpendicularity
measurement is superior to the accuracy of the perpendicular master. This paper proposes two new methods that can
measure axis perpendicularity without using a perpendicular master. Absolute axis perpendicularity measurement can be
achieved by vision system. The feasibility of our developed measurement methods are confirmed by several