Deep Imitation Learning for Humanoid Loco-manipulation through Human Teleoperation

We tackle the problem of developing humanoid loco-manipulation skills with deep imitation learning. The difficulty of collecting task demonstrations and training policies for humanoids with a high degree of freedom presents substantial challenges. We introduce TRILL, a data-efficient framework for training humanoid loco-manipulation policies from human demonstrations. In this framework, we collect human demonstration data through an intuitive Virtual Reality (VR) interface. We employ the whole-body control formulation to transform task-space commands by human operators into the robot's joint-torque actuation while stabilizing its dynamics. By employing high-level action abstractions tailored for humanoid loco-manipulation, our method can efficiently learn complex sensorimotor skills. We demonstrate the effectiveness of TRILL in simulation and on a real-world robot for performing various loco-manipulation tasks. Videos and additional materials can be found on the project page: https://ut-austin-rpl.github.io/TRILL.Comment: Submitted to Humanoids 202

Effects of nanofluids containing graphene/graphene-oxide nanosheets on critical heat flux

The superb thermal conduction property of graphene establishes graphene as an excellent material for thermal management. In this paper, we selected graphene/graphene oxide nanosheets as the additives in nanofluids. The authors interestingly found that the highly enhanced critical heat flux (CHF) in the nanofluids containing graphene/graphene-oxide nanosheets (GON) cannot be explained by both the improved surface wettability and the capillarity of the nanoparticles deposition layer. Here we highlights that the GON nanofluid can be exploited to maximize the CHF the most efficiently by building up a characteristically ordered porous surface structure due to its own self-assembly characteristic resulting in a geometrically changed critical instability wavelength.open363

Aggression and Harm-Avoidant Trait Impede Recovery From Internet Gaming Disorder

Background: Relatively little is known about which neuropsychological factors promote recovery from Internet gaming disorder (IGD).Methods: With informed consents, a cohort study was conducted in Seoul metropolitan area, South Korea, to investigate the course of IGD in youths. At baseline, we assessed psychosocial measures and gaming related measures such as Young's Internet Addiction Test (IAT) and the Aggression Questionnaire. The Balloon Analog Risk Task was also performed to study risk-taking behavior. A total of 60 subjects demonstrating three or greater criteria in the diagnostic interviews on IGD and the IAT score of 50 or above were included. After brief parental coaching at baseline, the participants were followed up at 3 and 6 months (n = 31). The baseline characteristics were compared between the non-improved group (<10% improvement in IAT score) and the improved group (≥30% improvement in IAT score) using Mann-Whitney U-test or chi-squared tests with a two-tailed statistical significance of 0.05.Results: The non-improved group and the improved group did not demonstrate significant differences regarding demographics or the IAT scores at baseline. However, the IAT scores were significantly higher in the non-improved group at both 3 and 6 months. The non-improved group was also more likely to display higher aggression and harm avoidance than the improved group at baseline.Discussion: Youths with excessive gaming problems should be evaluated for aggression and harm avoidance since they contributed to a worse prognosis. For those with high aggression or harm avoidance, more active therapeutic interventions should be considered

Early Growth, Pigmentation, Protein Content, and Phenylalanine Ammonia-lyase Activity of Red Curled Lettuces Grown under Different Lighting Conditions

Early growth, pigmentation, protein content, and phenylalanine ammonia-lyase (PAL) activity of red curly lettuces (Lactuca sativa L.) grown under different lighting conditions were investigated. Fluorescent lamps (control), blue, red, and blue plus red light-emitting diodes (LEDs) were used as light sources for 10 days. An equal proportion (1:1) of blue and red LEDs was used in the mixed radiation condition. Compared with the control, monochromic red or blue lighting increased fresh and dry weights of 'Ttuksum' and 'Jaju' lettuces. Anthocyanin synthesis was also significantly promoted by the mixed radiation of blue and red LEDs. The mixed radiation also increased the protein content and PAL enzyme activity of 'Ttuksum' leaves by about 200% compared to other treatments. Anthocyanin content was the highest in lettuces subjected to the mixture radiation of blue and red light treatment, while anthocyanin synthesis was inhibited by monochromic red light. The results of the present study indicate that growth and pigment synthesis in lettuces are significantly enhanced by exposure to mixed radiation from blue and red LEDs.This study was carried out with the support of Research Program for Agricultural Science & Technology Development (Project No. PJ0076662011), National Academy of Agricultural Science, Rural Development Administration, Republic of Korea.OAIID:oai:osos.snu.ac.kr:snu2012-01/102/0000027607/2SEQ:2PERF_CD:SNU2012-01EVAL_ITEM_CD:102USER_ID:0000027607ADJUST_YN:YEMP_ID:A075898DEPT_CD:517CITE_RATE:.237FILENAME:2012-2-kjhst-led적치마상추-허정욱.pdfDEPT_NM:식물생산과학부EMAIL:[email protected]_YN:NCONFIRM:

Delayed Diagnosis of an Intraurethral Foreign Body Causing Urosepsis and Penile Necrosis

Cases of self-inserted foreign bodies in the male urethra and urinary bladder are unusual. In most cases, the type of foreign body can be identified by taking a history or from radiological findings; sometimes, however, it is difficult to identify the foreign body because of decreased mental capacity of the patient or unknown radiological characteristics of the foreign body. We experienced a chronic alcoholic patient with septicemia and penile necrosis in whom a fragment of mirror glass had passed through the urethra into the bladder. The glass, 2 cm in length and 0.7 cm in diameter, was detected by cystoscopy and was removed by using a resectosope

Operational space control of compliant isoelastic robots and their interaction with an DIARC cognitive architecture

For robots to be successfully deployable in human environments where they are required to complete tasks through human interactions, the robots need to be equipped with new capabilities to execute tasks commanded by humans, and they must be aware of their environments through exteroceptive sensors while understanding human intentions. With such capabilities, the robots can become assistants to non-expert users in daily life. This thesis presents and evaluates methodologies for robots to fulfill such demands. Chapter 2 presents an operational space controller (OSC) for constrained and underactuated robotic manipulators to enable the effective execution of tracking tasks. The advantages of operational space control compared to inverse kinematics-based control are also discussed and it is shown that the controller is suitable for executing multiple hierarchical tasks. Simulation and hardware experiments will allow us to demonstrate that our controllers allow robots to accurately manipulate objects. Chapter 3 proposes a control framework for intelligent robots, which interact with human users through spoken languages and understand the environment via a vision system. The framework consists of two modules: A Distributed Integrated Affect Reflection and Cognition (DIARC) module and a Planning and Control for robots (PnC) module. DIARC enables robots to quickly learn task-relevant objects and action sequences online from observations, human demonstrations, and instructions and to apply the learned knowledge during task execution. The PnC module allows robots to generate task-related trajectories and to precisely track these trajectories. Our simulation and hardware experiments demonstrate the proposed control framework can make robots perform various tasks as commanded by non-expert users using voice commands. The main contribution of this thesis is: (1) the development of an OSC that takes into account the constrained and underactuated properties of isoelastic robots, and (2) the integration and deployment of the DIARC cognitive architecture.Aerospace Engineerin