Using distributed systems in real-time control of autonomous vehicles

Robotica ◽  
2003 ◽  
Vol 21 (3) ◽  
pp. 271-281 ◽  
Author(s):  
Urbano Nunes ◽  
José Alberto Fonseca ◽  
Luís Almeida ◽  
Rui Araújo ◽  
Rodrigo Maia

In this paper distributed architectures for autonomous vehicles are addressed, with a special emphasis on its real-time control requirements. The interconnection of the distributed intelligent subsystems is a key factor in the overall performance of the system. To better understand the interconnection requirements, the main techniques and modules of a global navigation system are described. A special focus on fieldbuses properties and major characteristics is made in order to point out some potentialities, which make them attractive in autonomous vehicles real-time applications, either in terms of reliability as in terms of real-time restrictions.

Author(s):  
Mohamed Hussein Agamy ◽  
Fahe M. Ellithy ◽  
Adel S. Nada

This paper presents a tested proposal scheme to connect a DFIG driven by a wind turbine to the public grid. This scheme was implemented to drive an automatic transfer switch (ATS). Control of the phase sequence, phase difference, and the frequency of the injected power are achieved using these proposed control circuits. These circuits are practically implemented and laboratory tested. The system allows monitoring the rated frequency, synchronization, and fundamental magnitude. Simulation software such as Multi Sim and Proteus are used for system validation and compatibility. The implemented circuits are used for re-scaling the grid voltage to the logic level for real time comparison and calculations. In addition to the feature of data monitoring, the system can also log these data for the system debugging purposes. The system can be considered as a real time control where the measurements and the correction are made in few milliseconds (fractions of the fundamental cycle). The lower cost control circuits are implemented using an Arduino kit in addition to a discrete digital component. The simulation and experimental results are in satisfactory agreement showing the most salient features of this system.


2005 ◽  
Vol 15 (08) ◽  
pp. 2349-2360 ◽  
Author(s):  
LEONARDO A. B. TÔRRES ◽  
LUIS ANTONIO AGUIRRE

This paper describes a laboratory setup suitable for implementing low cost real-time solutions in the fields of control, synchronization and information transmission based on chaotic oscillators. The setup has the following features: (a) it is composed of a Chua oscillator furnished with three actuators thus permitting mono- and multi-variable control; (b) the actuators can be driven by the analog outputs of a standard I/O-board; in order to be able to actuate fast enough (c) the I/O-board is driven by a real time program written for Linux and (d) an inductorless implementation of Chua's circuit permits to slow down the original dynamics to just a few hertz. This enables implementing sophisticated control schemes without severe time restrictions. The paper concludes with a sample of experiments performed using the new setup.


Electronics ◽  
2019 ◽  
Vol 8 (11) ◽  
pp. 1328 ◽  
Author(s):  
Hsu-Chih Huang ◽  
Chin-Wang Tao ◽  
Chen-Chia Chuang ◽  
Jing-Jun Xu

This study presents a field-programmable gate array (FPGA)-based mechatronic design and real-time fuzzy control method with computational intelligence optimization for omni-Mecanum-wheeled autonomous vehicles. With the advantages of cuckoo search (CS), an evolutionary CS-based fuzzy system is proposed, called CS-fuzzy. The CS’s computational intelligence was employed to optimize the structure of fuzzy systems. The proposed CS-fuzzy computing scheme was then applied to design an optimal real-time control method for omni-Mecanum-wheeled autonomous vehicles with four wheels. Both vehicle model and CS-fuzzy optimization are considered to achieve intelligent tracking control of Mecanum mobile vehicles. The control parameters of the Mecanum fuzzy controller are online-adjusted to provide real-time capability. This methodology outperforms the traditional offline-tuned controllers without computational intelligences in terms of real-time control, performance, intelligent control and evolutionary optimization. The mechatronic design of the experimental CS-fuzzy based autonomous mobile vehicle was developed using FPGA realization. Some experimental results and comparative analysis are discussed to examine the effectiveness, performance, and merit of the proposed methods against other existing approaches.


1977 ◽  
Vol 12 (1) ◽  
pp. 1-26
Author(s):  
R. Bedrosyan ◽  
J. Ganczarczyk

Abstract In urban centres, the degree of pollution from combined sewer overflows and stormwater runoff is becoming ever more noticeable and critical. Among the many stormwater management alternatives for combined sewer overflow abatement, remote monitoring/real-time control is emerging as a cost-effective method in large urban centres. Its advantage is that it does not require additional facilities, but uses the existing system more effectively. A general computer model is needed in the planning stage, which can estimate the overall performance of real-time control and other stormwater management alternatives, without employing expensive, single-event models like WREM. The well-established and most widely used initial planning model STORM is unable to provide an overall system description. Therefore, a new programme, named RAFFI, was devised which can be combined with STORM. The RAFFI is a simple model which provides hourly information on flows and pollutants (BOD and SS) diverted into receiving waters from various overflow points and treatment and by-pass operations at the plant. The model can simulate the overall behaviour of existing and proposed systems in multi-basin urban areas for single storms, or for many storms over a long period, such as one year. In-system storage can be simulated by assuming that the interceptor acts as a common reservoir which can store flows from all watersheds, while each trunk can store flows only from the watershed that it serves. Dynamic regulators can be simulated according to a built-in control strategy, which changes the flow capacity of diversion pipes and outfalls, based on plant, trunk and interceptor flow and storage values at each hour. Capacities for primary, secondary or by-pass operations at the plant can be varied during storms. Treatment of overflows at each outfall can also be simulated. The model is equally applicable to separate storm sewer systems. The objective was not to produce yet another new model, but to integrate programme RAFFI with STORM, in order to increase its capabilities in the initial planning stage. By using STORM-RAFFI, a decision-maker can estimate the overall performance of an existing system during wet


Author(s):  
Vemema Kangunde ◽  
Rodrigo S. Jamisola ◽  
Emmanuel K. Theophilus

AbstractThis paper presents related literature review on drones or unmanned aerial vehicles that are controlled in real-time. Systems in real-time control create more deterministic response such that tasks are guaranteed to be completed within a specified time. This system characteristic is very much desirable for drones that are now required to perform more sophisticated tasks. The reviewed materials presented were chosen to highlight drones that are controlled in real time, and to include technologies used in different applications of drones. Progress has been made in the development of highly maneuverable drones for applications such as monitoring, aerial mapping, military combat, agriculture, etc. The control of such highly maneuverable vehicles presents challenges such as real-time response, workload management, and complex control. This paper endeavours to discuss real-time aspects of drones control as well as possible implementation of real-time flight control system to enhance drones performance.


1995 ◽  
Vol 34 (05) ◽  
pp. 475-488
Author(s):  
B. Seroussi ◽  
J. F. Boisvieux ◽  
V. Morice

Abstract:The monitoring and treatment of patients in a care unit is a complex task in which even the most experienced clinicians can make errors. A hemato-oncology department in which patients undergo chemotherapy asked for a computerized system able to provide intelligent and continuous support in this task. One issue in building such a system is the definition of a control architecture able to manage, in real time, a treatment plan containing prescriptions and protocols in which temporal constraints are expressed in various ways, that is, which supervises the treatment, including controlling the timely execution of prescriptions and suggesting modifications to the plan according to the patient’s evolving condition. The system to solve these issues, called SEPIA, has to manage the dynamic, processes involved in patient care. Its role is to generate, in real time, commands for the patient’s care (execution of tests, administration of drugs) from a plan, and to monitor the patient’s state so that it may propose actions updating the plan. The necessity of an explicit time representation is shown. We propose using a linear time structure towards the past, with precise and absolute dates, open towards the future, and with imprecise and relative dates. Temporal relative scales are introduced to facilitate knowledge representation and access.


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