Development of a Biped Walking Robot Controller Based on a Embedded System

In this paper, we have made a new motion controller and the embedded ARM board to control the biped walking robot. As a control system for the robot, a distributed control system composed of the main controllers and the motor controller for the robot using the one-chip microprocessor were developed. The main controller and the motor controller composed as a distributed control system were developed using the embedded ARM board and the TMS320c2407 processor, respectively. A new trajectory tracking algorithm for the motor controller appropriate for the one-chip microprocessor was devised employing pre-generated off-line trajectory data. Also, the robot composed of an operation system of the ARM board based on the real-time LINUX was developed. In addition to these, a CAN communication system was developed to process the complex control system. Some tests and their results were presented to validate superior performance of the developed system.Abstract = 5 기호설명 = 6 그림목차 = 7 표목차 = 8 1. 서론 = 9 1.1 연구배경 = 9 1.2 연구 목적 및 내용 = 10 2. 이족보행로봇의 구조 및 해석 = 11 2.1 로봇의 기구적 구조 = 11 2.1.1 구동 액츄에이터 = 12 2.2 로봇의 관절구조 = 13 2.2.1 허리관절의 구조 = 14 2.2.2 무릎관절의 구조 = 16 2.2.3 발목관절의 구조 = 19 3.모션 제어기의 설계 = 24 3.1 관절 구동모터 제어기의 hardware 구성 = 24 3.2 관절 구동모터 경로 및 제어알고리즘 설계 = 28 4. 로봇의 상위 제어시스템 설계 및 CAN통신 구현 = 33 4.1 임베디드 시스템 = 33 4.1.1 임베디드 시스템 개요 = 33 4.1.2 임베디드 운영체제와 실시간 임베디드 리눅스 = 34 4.2 ARM보드를 이용한 제어시스템 설계 = 37 4.2.1 포팅 = 42 4.2.2 디바이스 드라이버 설치 = 46 4.2.3 애플리 케이션 개발 = 48 4.3 CAN통신 = 51 4.3.1 시스템 개요 = 52 4.3.2 CAN 프로토콜 계층모델 = 53 4.3.3 DSP2007을 이용한 CAN통신 구현 = 55 5. 실험 및 고찰 = 57 5.1 모터의 경로제어 시험 = 57 5.2 로봇의 보행실험 = 59 6. 결론 = 61 참고문헌 = 62 부록 = 6

Obesity increases airway hyperresponsiveness via the TNF-α pathway and treating obesity induces recovery

Obesity is a known risk factor for allergic asthma. It has been recognized as a key player in the pathogenesis of several inflammatory disorders via activation of macrophages, which is also vital to the development of allergic asthma. We investigated the mechanism of obesity-related asthma and whether treating obesity through exercise or diet ameliorates the severity of asthma in the obesity-related asthma model. We generated diet-induced obesity (DIO) in C57BL/6 mice by high-fat-feeding and ovalbumin-induced asthma (lean-OVA or DIO-OVA). The DIO-OVA mice were then treated with tumor necrosis factor (TNF)-α neutralizing antibody as a TNF-α blockade or a Cl2MDP-containing liposome to induce an alveolar macrophage deficiency. To treat obesity, the DIO-OVA mice were under dietary restrictions or exercised. The pathophysiological and immunological responses were analyzed. Airway hyperresponsiveness (AHR), serum IgE and TNF-α levels in the lung tissue increased in the DIO-OVA mice compared to the lean-OVA mice. Both the TNF-α blockade and depletion of alveolar macrophages in the DIO-OVA mice decreased AHR compared to the DIO-OVA mice. Treating obesity by exercise or through dietary means also reduced pulmonary TNF-α levels and AHR in the DIO-OVA mice. These results suggest that restoring normal body weight is an appropriate strategy for reducing TNF-α levels, and controlling inflammation may help improve asthma severity and control in obesity-related asthma.ope

Alveolar macrophages play a key role in cockroach-induced allergic inflammation via TNF-α pathway

The activity of the serine protease in the German cockroach allergen is important to the development of allergic disease. The protease-activated receptor (PAR)-2, which is expressed in numerous cell types in lung tissue, is known to mediate the cellular events caused by inhaled serine protease. Alveolar macrophages express PAR-2 and produce considerable amounts of tumor necrosis factor (TNF)-α. We determined whether the serine protease in German cockroach extract (GCE) enhances TNF-α production by alveolar macrophages through the PAR-2 pathway and whether the TNF-α production affects GCE-induced pulmonary inflammation. Effects of GCE on alveolar macrophages and TNF-α production were evaluated using in vitro MH-S and RAW264.6 cells and in vivo GCE-induced asthma models of BALB/c mice. GCE contained a large amount of serine protease. In the MH-S and RAW264.7 cells, GCE activated PAR-2 and thereby produced TNF-α. In the GCE-induced asthma model, intranasal administration of GCE increased airway hyperresponsiveness (AHR), inflammatory cell infiltration, productions of serum immunoglobulin E, interleukin (IL)-5, IL-13 and TNF-α production in alveolar macrophages. Blockade of serine proteases prevented the development of GCE induced allergic pathologies. TNF-α blockade also prevented the development of such asthma-like lesions. Depletion of alveolar macrophages reduced AHR and intracellular TNF-α level in pulmonary cell populations in the GCE-induced asthma model. These results suggest that serine protease from GCE affects asthma through an alveolar macrophage and TNF-α dependent manner, reflecting the close relation of innate and adaptive immune response in allergic asthma model.ope

Endotoxin is not essential for the development of cockroach induced allergic airway inflammation

PURPOSE: Cockroach (CR) is an important inhalant allergen and can induce allergic asthma. However, the mechanism by which CR induces airway allergic inflammation and the role of endotoxin in CR extract are not clearly understood in regards to the development of airway inflammation. In this study, we evaluated whether endotoxin is essential to the development of CR induced airway allergic inflammation in mice. MATERIALS AND METHODS: Airway allergic inflammation was induced by intranasal administration of either CR extract, CR with additional endotoxin, or endotoxin depleted CR extract, respectively, in BALB/c wild type mice. CR induced inflammation was also evaluated with toll like receptor-4 (TLR-4) mutant (C3H/HeJ) and wild type (C3H/HeN) mice. RESULTS: Intranasal administration of CR extracts significantly induced airway hyperresponsiveness (AHR), eosinophilic and neutrophilic airway inflammation, as well as goblet cell hyperplasia in a dose-dependent manner. The addition of endotoxin along with CR allergen attenuated eosinophilic inflammation, interleukin (IL)-13 level, and goblet cell hyperplasia of respiratory epithelium; however, it did not affect the development of AHR. Endotoxin depletion in CR extract did not attenuate eosinophilic inflammation and lymphocytosis in BAL fluid, AHR and IL-13 expression in the lungs compared to CR alone. The attenuation of AHR, eosinophilic inflammation, and goblet cell hyperplasia induced by CR extract alone was not different between TLR-4 mutant and the wild type mice. In addition, heat inactivated CR extract administration induced attenuated AHR and eosinophilic inflammation. CONCLUSION: Endotoxin in CR extracts may not be essential to the development of airway inflammation.ope

Intranasal Administration of Unmethylated CpG with Cockroach Antigen Prevents the Development of Cockroach-Induced Allergic Inflammation

Background: Unmethylated CpG can induce Th1 and regulatory T cell immune responses and may modulate ovalbumin-induced mouse allergic asthma. However, the effects of CpG in a cockroach allergen asthma model have not yet been elucidated. Objective: To evaluate whether unmethylated CpG can prevent the development of indoor allergen-induced allergic asthma. Methods: Effects of CpG were evaluated using a cockroach allergen-induced mouse model. CpG and Blattella germanica (CR) allergen were co-administered intranasally, and methacholine airway hyperresponsiveness (MCh-AHR), inflammatory cells and cytokine profiles in BAL fluid and lung histology were evaluated. Result: Co-administration of CpG with CR allergen can prevent the development of MCh-AHR and allergic inflammation in a CR-induced asthma mouse model. Eosinophils, lymphocytes, macrophages and neutrophils in BAL fluid were decreased by the co-administration of unmethylated CpG in an OVA-induced asthma model. The expression of IL-5, IL-13 and IFN-γ in BAL fluid was attenuated by the CpG. Peribronchial, perivascular inflammation, and goblet cell hyperplasia in respiratory epithelium were also markedly attenuated by the CpG. Conclusion: These findings suggest that unmethylated CpG may have role in the immune modulation of allergic asthma induced by indoor allergensope

Acute exposure to silica nanoparticles aggravate airway inflammation: different effects according to surface characteristics

Silica nanoparticles (SNPs) are widely used in many scientific and industrial fields despite the lack of proper evaluation of their potential toxicity. This study examined the effects of acute exposure to SNPs, either alone or in conjunction with ovalbumin (OVA), by studying the respiratory systems in exposed mouse models. Three types of SNPs were used: spherical SNPs (S-SNPs), mesoporous SNPs (M-SNPs), and PEGylated SNPs (P-SNPs). In the acute SNP exposure model performed, 6-week-old BALB/c female mice were intranasally inoculated with SNPs for 3 consecutive days. In the OVA/SNPs asthma model, the mice were sensitized two times via the peritoneal route with OVA. Additionally, the mice endured OVA with or without SNP challenges intranasally. Acute SNP exposure induced significant airway inflammation and airway hyper-responsiveness, particularly in the S-SNP group. In OVA/SNPs asthma models, OVA with SNP-treated group showed significant airway inflammation, more than those treated with only OVA and without SNPs. In these models, the P-SNP group induced lower levels of inflammation on airways than both the S-SNP or M-SNP groups. Interleukin (IL)-5, IL-13, IL-1β and interferon-γ levels correlated with airway inflammation in the tested models, without statistical significance. In the mouse models studied, increased airway inflammation was associated with acute SNPs exposure, whether exposed solely to SNPs or SNPs in conjunction with OVA. P-SNPs appear to be relatively safer for clinical use than S-SNPs and M-SNPs, as determined by lower observed toxicity and airway system inflammation.ope

반사형 반강유전성 액정 디스플레이의 전기광학 특성에 관한 연구

학위논문(석사)--서울대학교 대학원 :전기·컴퓨터공학부,2002.Maste

Synthesis of Tridentate Bis(oxazoline)Derivatives andTheir Application to Asymmetric Reactions

Maste

WEPP 모형을 이용한 토양유실량 추정

학위논문(석사)--서울대학교 대학원 :농공학과 농업토목전공,2002.Maste

Study on The Alignment and Phase of Liquid Crystal Interacting with Thin Polymer Blend, Modulated SAM, or Polycrystalline-Graphene/(PDMS) Surface

Doctor자연계에는 수 많은 종류의 액정상이 존재하며, 생명체 및 비유기체에서도 중요한 역할을 하고 있다. 액정의 방향자는 액정-액정, 액정-표면 그리고 액정-장(場) 간(間)의 상호작용에 의한 에너지의 평형에 의하여 정해지게 된다. 본 논문은 액정의 방향자와 상변화를 광학적으로 관찰하므로서 액정과 표면의 상호작용을 이해하고자 하였다. 3장과 4장에서는, 액정방향자의 편각(偏角)과 방위각(方位角)을 액정을 둘러싸고 있는 표면을 조절하였으며 제어하였으며, 5장에서는 역으로 그래핀 시트에 접속하고 있는 액정의 방향자를 관찰하므로서 그래핀시트의 특성을 짐작해 보았다.1장은 액정의 탄성력, 질서도, 전기적, 광학적성질과 같은 기본물성과 발견, 배향기제 그리고 액정디스플레이와 같은 간단한 응용에 대하여 자세하게 다루었으며, 자기조립단분자막의 표면도 간단하게 소개하였다. 이 장은 뒤에 오는 장을 읽기전에 액정에 대한 기본 지식을 제공하기 위해서 작성되었다.표면의 특성을 파악할 수 있는 몇 몇 특이한 실험 방법에 대해서는 2장에 소개하였다.3장에서는, 고분자블랜드막의 두께가 액정의 선경사각에 어떤 영향을 주는지에 대하여 살펴보았다. 고분자 블랜드이 두께를 바꿈으로서 액정의 편각(偏角)을 제어할 수 있었으며, 이 현상을 고분자 블랜드막의 표면에너지와 연관 지어 설명하였다. 막의 두께를 제어하기 위하여 각기 다른 농도의 수직-, 수평-폴리이미드 전구체 혼합용액 준비하여 유리판에 코팅하였다. 코팅된 블랜드막은 가열하여 이미드화 하였다. 블랜드필름막과 수직배향막의 두께는 이들 막의 표면에너지변화에 영향을 주었으며, 이로 이용하여 선경사각을 5.5°부터 87°도까지 전 영역에 걸쳐 제어할 수 있었다. 이에 반하여 순수한 수평배향막의 두께는 표면에너지에 대하여 독립인자였다.액정의 방향자를 넓은 면적에 대하여 간단한 공정으로 세밀하게 그리고 원하는 모양으로 배향시키기 위해서, 보다 정교하게 고안된 표면을 4장에서 소개하였다. 간단한 장점을 지니고 있어서 일반적으로 많이 사용되는 “문지르기” 방법과 작은-크기 조절이 장점인 광 배향 방법은 연속적으로 방향을 변경하여 임의모양의 배향이 불가하다. 자기조립단분자막에 의한 임의모양의 배향방법은 아직까지 근본적인 문제점을 가지고 있었다. 또한 앞에 언급한 모든 방법들은 선경사각을 조절하는데 한계가 있다. 이 장에서는 다재 다능한 액정 배향이 가능하도록 하는 두 가지 방법[자체적으로 분자밀도 조절력을 가지는 표면처리방법(SDM)과 표면에 의한 상 분리현상을 이용한 제약 없는 탄성력 안정화 방법(OES)]을 소개하였다. 이러한 방법들을 이용하여 선경사각을 연속적으로 조절가능하고, 균일하면서도 여러 종류로 이루어지며, 결점이 없는 임의의 배향이 가능한 다재 다능한 액정배향을 비 접촉방식으로 만들 수 있음을 보여주었다.5장에서는, 다결정질-그래핀 표면의 비등방성을 액정배향을 관찰하여 살펴보았다. 또한 그래핀의 나노크기의 틈을 탐지할 수 있는 새로운 방법을 제안하였다. 그래핀막 하부에 위치한 polydimethylsiloxane (PDMS)으로 액정 혼합물 중 크기가 작고 소수성인 분자들이 그래핀의 깨어진 틈을 통하여 흡수됨으로써 네마틱상의 혼합액정이 스메틱상으로 변화게 되다. 이러한 상의 변화를 정량화 함으로서 그래핀의 틈을 정량화 하는 것이 가능하였다. 이러한 간단한 관찰방법은 신축성 있게 펴고 접을 수 있는 전자장치로의 활발한 응용이 진행되고 있는 그래핀의 전기, 기계적 특성을 평가하는데 유용한 방법을 제공할 것으로 보인다