Multi-cue 3D Object Recognition in Knowledge-based Vision-guided Humanoid Robot System

Abstract — A vision based object recognition subsystem on knowledge-based humanoid robot system is presented. Humanoid robot system for real world service application must integrate an object recognition subsystem and a motion planning subsystem in both mobility and manipulation tasks. These requirements involve the vision system capable of self-localization for navigation tasks and object recognition for manipulation tasks, while communicating with the motion planning subsystem. In this paper, we describe a design and implementation of knowledge based visual 3D object recognition system with multi-cue integration using particle filter technique. The particle filter provides very robust object recognition performance and knowledge based approach enables robot to perform both object localization and self localization with movable/fixed information. Since this object recognition subsystem share knowledge with a motion planning subsystem, we are able to generate vision-guided humanoid behaviors without considering visual processing functions. Finally, in order to demonstrate the generality of the system, we demonstrated several vision-based humanoid behavior experiments in a daily life environment. Fig. 1. system Behavior example of knowledge based vision guided humanoid I

Development of a Whole-body Work Imitation Learning System by a Biped and Bi-armed Humanoid

Imitation learning has been actively studied in recent years. In particular, skill acquisition by a robot with a fixed body, whose root link position and posture and camera angle of view do not change, has been realized in many cases. On the other hand, imitation of the behavior of robots with floating links, such as humanoid robots, is still a difficult task. In this study, we develop an imitation learning system using a biped robot with a floating link. There are two main problems in developing such a system. The first is a teleoperation device for humanoids, and the second is a control system that can withstand heavy workloads and long-term data collection. For the first point, we use the whole body control device TABLIS. It can control not only the arms but also the legs and can perform bilateral control with the robot. By connecting this TABLIS with the high-power humanoid robot JAXON, we construct a control system for imitation learning. For the second point, we will build a system that can collect long-term data based on posture optimization, and can simultaneously move the robot's limbs. We combine high-cycle posture generation with posture optimization methods, including whole-body joint torque minimization and contact force optimization. We designed an integrated system with the above two features to achieve various tasks through imitation learning. Finally, we demonstrate the effectiveness of this system by experiments of manipulating flexible fabrics such that not only the hands but also the head and waist move simultaneously, manipulating objects using legs characteristic of humanoids, and lifting heavy objects that require large forces.Comment: accepted at IROS202

Single-crystal SiC thin-film produced by epitaxial growth and its application to micro-mechanical devices

This paper deals with the fabrication process of single-crystal silicon carbide (SiC) thin-films and its application to microdevice. SiC thin-film was synthesized using molecular beam epitaxy, where single-crystal SiC layer was grown on single-crystal silicon (Si) substrate. Using lithography and etching process, microscopic cantilevers were fabricated. Typical dimensions of the cantilevers were 10-60 μm in length, 10-30 μm in width, typically 180 nm in thickness. Young\u27s modulus estimated from bending test was almost the same with that of bulk material. Finally, an application is demonstrated where nickel was deposited on the cantilever and biomorphic actuation was carried out. The displacement at the tip was about 2 μm when the temperature change was 40 K. The time constant of the step response was about 0.07 s

99m-Technetium galactosyl human serum albumin scanning to evaluate liver function after stereotactic body radiotherapy for hepatocellular carcinoma: A case report

The primary choice among treatment options for liver malignancies is surgery. However, if surgery cannot be performed, Stereotactic body radiotherapy (SBRT) may be effective. 99m-technetium galactosyl human serum albumin (GSA) single-photon emission computed tomography (SPECT) imaging is useful for the assessment of liver function before surgery. We report the case of a 77-year-old man who had undergone SBRT for hepatocellular carcinoma of the left lobe of the liver 2 years previously. Follow-up revealed a 15-mm hepatocellular carcinoma at the edge of the right lobe of the liver. 99m-technetium GSA SPECT was performed before SBRT to confirm that there was no accumulation in the left lobe and to ensure that there was good function of the right lobe. Three months after SBRT, the tumor had responded, and decreases in GSA accumulation were observed in line with the radiation beam. Because hepatocellular carcinoma often relapses, it is important to assess the anatomic site of liver dysfunction before and after radiation. This case demonstrates that 99m-technetium GSA SPECT is useful for this purpose

Gastric Carcinoid with Hypergastrinemia: Report of Three Cases

We report 3 cases of gastric carcinoids with hypergastrinemia. Case 1: A 60-year-old man had a 2 cm carcinoid of the stomach and underwent partial resection. Involvement of the muscularis propria and lymph nodes metastasis were observed microscopically. Follow-up gastroscopy revealed another carcinoid lesion and total gastrectomy was performed. Case 2: A 67-year-old woman with multiple carcinoids of the entire stomach underwent antrectomy. No growth of residual tumors has been detected so far. Case 3: A 61-year-old man had a tumor near the esophagogastric junction and underwent total gastrectomy. Carcinoid component was diffusely intermingled with adenocarcinoma in the tumor and invaded into the subserosa. In all 3 cases, the serum gastrin level was high and atrophic gastritis was microscopically observed. Carcinoid tumor in Case 3 was different from those in Cases 1 and 2 and interestingly, gastric carcinoid with hypergastrinemia showed various types of appearance

HumanMimic: Learning Natural Locomotion and Transitions for Humanoid Robot via Wasserstein Adversarial Imitation

Transferring human motion skills to humanoid robots remains a significant challenge. In this study, we introduce a Wasserstein adversarial imitation learning system, allowing humanoid robots to replicate natural whole-body locomotion patterns and execute seamless transitions by mimicking human motions. First, we present a unified primitive-skeleton motion retargeting to mitigate morphological differences between arbitrary human demonstrators and humanoid robots. An adversarial critic component is integrated with Reinforcement Learning (RL) to guide the control policy to produce behaviors aligned with the data distribution of mixed reference motions. Additionally, we employ a specific Integral Probabilistic Metric (IPM), namely the Wasserstein-1 distance with a novel soft boundary constraint to stabilize the training process and prevent model collapse. Our system is evaluated on a full-sized humanoid JAXON in the simulator. The resulting control policy demonstrates a wide range of locomotion patterns, including standing, push-recovery, squat walking, human-like straight-leg walking, and dynamic running. Notably, even in the absence of transition motions in the demonstration dataset, robots showcase an emerging ability to transit naturally between distinct locomotion patterns as desired speed changes

Ectopic varices in a right diaphragm that ruptured into the pleural cavity.

The term ectopic varices is used to describe dilated portosystemic collateral veins in unusual locations other than the gastroesophageal region. We recently experienced a rare case of ectopic varices that developed in the right diaphragm and ruptured into the pleural cavity. A 68-year-old female with hepatocellular carcinoma complicated with liver cirrhosis was admitted due to an acute onset of dyspnea and right bloody pleural effusion. Because of the patient's advanced hepatocellular carcinoma and poor condition, conservative therapies such as hemostats and blood transfusion were selected. Even though the bleeding to the pleural cavity stopped spontaneously, the patient died due to a progression of liver failure. Autopsy revealed a huge collateral vein in the right diaphragm. The etiology, prevalence, relationship with portal hypertension, and treatment of ectopic varices are discussed herein