Search Results

An advanced braking system had to be developed for a next-generation hybrid sports car with Sport Hybrid Super Handling All-Wheel Drive to achieve an intuitive brake feeling in a variety of driving conditions, ultimate track performance and reduction of CO2 emissions per vehicle. This paper outlines the integration of brake-by-wire with traditional high-performance braking hardware and describes the technology needed to achieve these goals. Key focus areas to generate these results were: brake feeling control, corner hardware specification considerations and brake cooling.

The Closed Ecology Experiment Facilities (CEEF) were installed to collect data for estimation of transfer of radionuclides from atmosphere to humans in the ecosystem. The first target among the radio-nuclides is 14C. In order to validate function of material circulation in an experimental system constructed in the CEEF, circulation of air constituents, water and materials in waste was demonstrated connecting the Closed Plant Experiment Facility (CPEF) and the Closed Animal and Human habitation Experiment Facility (CAHEF) of the CEEF, since 2005 to 2007. The CPEF has a Plant Cultivation Module (PCM), which comprises of three plant chambers illuminated solely by artificial lighting, one plant chamber illuminated by both natural and artificial lighting, a space for preparation, and an airlock, and a physical/chemical material circulation system.

We developed an Advanced Life Support systems scheduler (ALS scheduler) to back up the habitation experiments of Closed Ecology Experiment Facilities (CEEF), and integrated the Lagrangian decomposition and coordination method for a scheduling algorithm of the scheduler. Later research revealed that when comparing solutions obtained by the Lagrangian decomposition and coordination method and by a skilled operator, respectively, a schedule sought by the skilled operator has different features from those of a schedule sought by the Lagrangian decomposition and coordination method. This paper describes how to generate a schedule such as one created by a skilled operator, while reducing complexity by integrating empirical knowledge to the Lagrangian decomposition and coordination method.

A habitation experiment using the Closed Ecology Experiment Facilities was started in 2005. In the future, the stays will be gradually extended. We have been developing the three layered control software for a Control Computer System of the Closed Ecology Experiment Facilities in order to back up the habitation experiments. In this paper, we will show the development of an operation scheduling system for one of the three layers, such as at the planning and scheduling level, and discuss the development of a scheduling algorithm that does not cause the complexity of the ALS scheduler to be exponentially increased.

Closure experiments will be conducted using the Closed Plant Experiment Facility (CPEF) and the Closed Animal and Habitation Experiment Facility (CAHEF) of the Closed Ecology Experiment Facilities (CEEF). The CEEF behavioral Prediction System (CPS) has been developed to check the CEEF operation for the closure experiments in advance. For the development of CPS, a simulation program for CPEF had been developed and reported. A simulation program for CAHEF was developed, and combined with the simulation program for CPEF. This integrated simulation program was validated by data obtained from a habitation experiment conducted in CEEF.

In this paper, we describe the design of intelligent control software required for operating the Closed Ecology Experiment Facilities (CEEF) that we call Mini-Earth. We will develop intelligent control software by reconfiguring functions of a Control Computer System (CCS) for controlling the CEEF into three layers that consist of planning & scheduling, task, and control levels. In the last half of this paper, we will focus on the planning & scheduling level, and describe the operation scheduling problem of a CEEF gas circulation system using a Planning and Scheduling Language (PSL) to develop an Operation Schedule Interactive Generation system (OSIG).

This paper discusses the integration of intelligence into the supervision and control system of an Advanced Life Support System (ALSS). An ALSS is a complex, large-scale system that should be maintained solely by a small crew. Since an ALSS is operated far from Earth, the propagation delay of radio waves makes remote support from Earth difficult to implement immediately. Accordingly, an autonomous supervision and control system is essential. A supervision and control system comprises an automatic controller for ALSS equipment and crew who supervise the equipment conditions and operate it. The application of intelligent control to such an automatic controller reduces the load on the crew, allowing them to concentrate on their major missions. The concept of intelligent control proposed here is based on the SRK model that expresses human behavior with three cognitive behaviors. This paper utilizes simulation to verify the effectiveness of the proposed methods for intelligent control.

A Regenerative Life Support System (RLSS) is a system that establishes self-sustained material recycling and circulation within a space base on the Moon or Mars. This is a large-scale and complicated system comprising a lot of components such as humans, plants and material circulation system. A RLSS contains many factors with uncertainty, such as dynamics of plants and humans, and failure and performance deterioration of devices. In addition, a RLSS is a large-scale and complicated system extending gradually. An environment with uncertainty or a large-scale and complicated system may not be properly addressed by a centralized system. In particular, such a system cannot always gather accurate information in one center in a frequently shifting environment, thus appropriate processing may be difficult. Therefore, we tried autonomous decentralization of information or decision-making using a Multi-Agent System (MAS).

In the Closed Ecology Experiment Facilities (CEEF), with integrating the Closed Plantation Experiment Facilities (CPEF) and the Closed Animal Breading & Habitation Facilities (CABHF), closed habitation experiments without material exchange with the outside will be conducted after the 2005 fiscal year. Cultivation experiments of about 30 crops and the integrating test of the material circulation system required for the closed habitation experiments have been performed since 2000 fiscal year. Using data reported in these experiments, material circulation in CEEF is simulated based on the recent operation strategy, and the storage capacity needed for the buffer of an air processing subsystem was estimated. In order for two humans to dwell over 120 days, the storage capacities of the carbon dioxide tank, the oxygen tank, and the waste gas tank in CPEF, and the carbon dioxide tank and the oxygen tank in CABHF are 820 g, 2830 g, 4425 g, 1780 g, and 1792 g, respectively.

For validation of operation schedules for the Closed Ecology Experiment Facilities (CEEF), development of the CEEF behavioral prediction system (CPS) has been started. The CPS will be simulated using the CEEF operation schedule. The CPS will gather data on quantities of materials in each component of the CEEF and operational status of each component at the start of the simulation, and configure them as the initial conditions of the simulation. For requirements of experiments, the simulation program for the CPS should be easy to adapt for changes of components and object materials. Because the CEEF is a nonlinear system, available period of the simulation is important. A flexible algorithm for the changes was developed. The simulation was available for three days to validate.

The purpose of Regenerative Life Support Systems (RLSS) is to support human life by regenerating resources. To date, the design procedure of RLSS has not been generalized as compared with that for automobiles, airplanes, ships or others entities. In this paper, we first analyzed the sub-goals needed to achieve the top-level goal of “support human life by regenerating resources”. This was done by extracting functions to describe each sub-goal and expressing the design process in a hierarchical manner. Next, we proposed the design methodology of determining element attributes to achieve these functions. Furthermore, in this design methodology, the element attributes of systems were determined to ensure the robustness of the systems against unexpected events in material circulation. In this paper, we discuss a generalized-conceptual design methodology for RLSS and apply that concept to Bioregenerative Life Support Systems (BRLSS).

A simulation of an open mode system experiment was run using the same experimental conditions as an integration test conducted from September 1999 to February 2000 using the Closed Plant Experiment Facility at the Institute for Environmental Sciences in order to evaluate the operation of closed mode system to be conducted in future. Operation of the open mode system experiment required a supply of water and carbon dioxide from the outside, and the discharge of nutrient waste water and oxygen. The present simulation verified the feasibility of using non-integrated wet-oxidation processor, nutrient synthesis unit and nutrient waste water processor connected within a closed mode system, and it was confirmed that sufficient material circulation could be achieved when rice and soybeans were divided into six beds with different growing stages to facilitate control of the nutrient solution.

Simulation of material circulation for a closed experiment using CEEF consisting of a plant and human system was performed. Initial set of materials contained in CEEF was decided by a decision procedure. Before the closure where the plant system is operated independently, the plant system (CPEF) needs gas exchange of O2 and CO2 with the outside. After the closure where the plant and human system are operated in a cooperation mode with mutual material exchange, no exchange of materials is needed. The closure time corresponds to the longest cultivation period to be cultivated in CPEF.

When discussing how to design and control a Closed Ecology Life Support System (CELSS), element-level calculations should be performed on materials circulating in the system. Performing these calculations through computer simulation allows great advantages, especially when analyzing a CELSS for applications having various forms at experimental facilities. In the present study, models for analyzing the balance and circulation of CELSS materials are developed, and material balance analysis software for CELSS (MBASC) and material circulation analysis software for CELSS (MCASC) are created using these models. The present paper proposes a new method for integrating an entire CELSS and controlling material circulation through the analysis of CELSS material circulation using the proposed software.

The closed ecology experiment facilities(CEEF) are comprised of an animal breeding & habitation module, plant module, and a geo-hydrosphere module(currently being established), which are composed of physicochemical devices to allow almost all the material to be circulated. Partial test operations are now in progress with these kinds of equipment, and cooperative operations between an animal breeding & habitation module and plant module are expected to be started in the near future. Balance of the material and equipment performance as the whole of the system are being tested, and material circulation in a variety of operation modes is being examined. Keeping such a situation in mind, analysis is made in this report for material circulation in the plant module by itself for operations based on the equipment design data.

Material circulations in a lunar base were simulated in consideration of an optimum control of electric power distributions to equipment. The base is composed of habitation and cultivation modules. The simulations of a dynamic logistic problem were conducted by the use of a fuzzy programming method, after doing the biochemical stoichiometric formulation of crew-, plant-, and machine-subsystems in living and growing modules. The simulation model could treat material circulation and electric power distribution in space systems and it could be expected to make this tool powerful combining this with experimental data.

The importance of system design in the field of mechanical engineering has been increasingly recognized recently. But suitable and useful methods for machine design are not yet established. So we must derive easy and useful designing methods for each machine element. We derived a new designing method by linear graph theory and analyzed the results of the dynamic behaviour of a power transmission mechanism as an example. And we understand that the mechanisms which are subject to restrictions of high accuracy and high performance must be designed by considering the characteristic of each machine element. This report deals with a more general power transmission mechanism containing a motor, bearing, support an so on, and analyzes the results of dynamic behaviour. Provided that the analytical model and system graph as in this report are prepared for the mechanism, the performance of the mechanism is easily grasped by this method.