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Abstract To investigate the effect of the surface roughness of 3D-metal-printed sub-THz components, the WR-10 3-inch-long waveguide and 24 dBi rectangular horn antenna were 3D-metal-printed using a titanium alloy powder and a high-resolution 3D metal printer. The characterized surface roughness of the printed components was 17.27 µm in RMS from a 3D optical surface profiler, and a nodule ratio of 7.89 µm and surface ratio of 1.52 for Huray model from the analyzed SEM images. The measured results of the 3D-metal-printed waveguide and rectangular horn antenna were compared with the ones of commercial waveguide and horn antenna having the same shapes. The 3D-metal-printed waveguide has 4.02 dB higher loss than the commercial waveguide, which may be caused by an ohmic loss of 0.85 dB and a surface roughness loss of 2.81 dB. The 3D-metal-printed horn antenna has 2 dB higher loss then the commercial horn antenna, which may be caused by an ohmic loss of 0.2 dB, surface roughness of 0.1 dB and fabrication tolerance loss of 1.7 dB. The loss separation was done from the EM simulation by changing the conductor material and surface roughness. 

sPHENIX is a next-generation detector experiment at the Relativistic Heavy Ion Collider, designed for a broad set of jet and heavy-flavor probes of the Quark-Gluon Plasma created in heavy ion collisions. In anticipation of the commissioning and first data-taking of the detector in 2023, a RIKEN-BNL Research Center (RBRC) workshop was organized to collect theoretical input and identify compelling aspects of the physics program. This paper compiles theoretical predictions from the workshop participants for jet quenching, heavy flavor and quarkonia, cold QCD, and bulk physics measurements at sPHENIX. 

Abstract Enhancing physical human-robot interaction requires the improvement in the tactile perception of physical touch. Robot skin sensors exhibiting piezoresistive behavior can be used in conjunction with collaborative robots. In past work, fabrication of these tactile arrays was done using cleanroom techniques such as spin coating, photolithography, sputtering, wet and dry etching onto flexible polymers. In this paper, we present an addictive, non-cleanroom improved process of depositing PEDOT: PSS, which is the organic polymer responsible for the piezoresistive phenomenon of the robot skin sensor arrays. This publication details the patterning of the robot skin sensor structures and the adaptation of the inkjet printing technology to the fabrication process. This increases the possibility of scaling the production output while reducing the cleanroom fabrication cost and time from an approximately five-hour PEDOT: PSS deposition process to five minutes. Furthermore, the testing of these skin sensor arrays is carried out on a testing station equipped with a force plunger and an integrated circuit designed to provide perception feedback on various force load profiles controlled in an automated process. The results show uniform deposition of the PEDOT: PSS, consistent resistance measurement, and appropriate tactile response across an array of 16 sensors. 

Advanced applications for human-robot interaction require perception of physical touch in a manner that imitates the human tactile perception. Feedback generated from tactile sensor arrays can be used to control the interaction of a robot with their environment and other humans. In this paper, we present our efforts to fabricate piezoresistive organic polymer sensor arrays using PEDOT: PSS or poly (3,4-ethylenedioxythiophene)-poly(styrenesulfonate). Sensors are realized as strain-gauges on Kapton substrates with thermal and electrical response characteristics to human touch. In this paper, we detail fabrication processes associated with a Gold etching technique combined with a wet lift-off photolithographic process to implement a circular tree designed sensor microstructure in our cleanroom. The testing of this microstructure is done on a load testing apparatus facilitated by an integrated circuit design. Furthermore, a lamination process is employed to compensate for temperature drift while measuring pressure for double-sided sensor substrates. Experiments carried out to evaluate the performance of the fabricated structure, indicates 100% sensor yields with the updated technique implemented.