scholarly journals Designing LQR Controllers for an Active Anti-roll Bar System with a Flexible Frame Model of a Single Unit Heavy Vehicle

Author(s):  
Van Tan Vu ◽  
Van Da Tran ◽  
Quoc Trung Pham ◽  
Manh Hung Truong ◽  
Oliver Sename ◽  
...  

Rollover accidents of heavy vehicles often cause serious consequences both in terms of vehicle and environmental damage as well the loss or injury of drivers, passengers and ordinary civilians. Currently, the active anti-roll bar system is considered as the most effective solution in enhancing vehicle roll stability. In this paper, we firstly investigated the role of a flexible frame of a single unit heavy vehicle in the rollover process. This approach is an important step forward in the research of the active anti-roll bar system. Then, the LQR control method is applied in designing controllers for the active anti-roll bar control system with this frame model. The active torque of the anti-roll bar system is considered as the control signal. The simulation results in the frequency and time domains with a double lane change maneuver show that the vehicle’s roll stability is improved by over 30 % compared to a vehicle using a passive anti-roll bar system.

Author(s):  
Alessandro D'Adda

The article deals with the role of the restitutio in integrum in case of environmental damage and the residual room for the monetary compensation in this field.


Author(s):  
N. I. Rajapakse ◽  
G. S. Happawana ◽  
Y Hurmuzlu

The current paper presents a robust control method that combines sliding-mode control (SMC) and quantitative feedback theory (QFT) for designing a driver seat of a heavy vehicle to reduce driver fatigue. A mathematical model is considered to analyse tracking control characteristics through computer simulation in order to demonstrate the effectiveness of the proposed control methodology. The SMC is used to track the trajectory of the desired motion behaviour of the seat. However, when the system enters into sliding regime, chattering occurs owing to switching delays as well as vehicle system vibrations. The chattering is eliminated with the introduction QFT inside the boundary layer to ensure smooth tracking. Furthermore, using SMC alone requires higher actuator forces for tracking than using both the control schemes together, and causes various problems in selecting hardware. Problems with noise amplification, resonances, presence of uncertainties, and unmodelled high-frequency dynamics can largely be avoided with the use of QFT over other optimization methods. The main contribution of the present paper is to provide guidance in designing the controller to reduce heavy vehicle seat vibration so that the driver's sensation of comfort maintains a certain level at all times.


Author(s):  
Brittany Goldsmith ◽  
Elizabeth Foyt ◽  
Madhu Hariharan

As offshore field developments move into deeper water, one of the greatest challenges is in designing riser systems capable of overcoming the added risks of more severe environments, complicated well requirements and uncertainty of operating conditions. The failure of a primary riser component could lead to unacceptable consequences, including environmental damage, lost production and possible injury or loss of human life. Identification of the risks facing riser systems and management of these risks are essential to ensure that riser systems operate without failure. Operators have recognized the importance of installing instrumentation such as global positioning systems (GPS), vessel motion measurement packages, wind and wave sensors and Acoustic Doppler Current Profiler (ADCP) units to monitor vessel motions and environmental conditions. Additionally, high precision monitoring equipment has been developed for capturing riser response. Measured data from these instruments allow an operator to determine when the limits of acceptable response, predicted by analysis or determined by physical limitations of the riser components, have been exceeded. Regular processing of measured data through automated routines ensures that integrity can be quickly assessed. This is particularly important following extreme events, such as a hurricane or loop current. High and medium alert levels are set for each parameter, based on design analysis and operating data. Measured data is compared with these alert levels, and when an alert level is reached, further response evaluation or inspection of the components in question is recommended. This paper will describe the role of offshore monitoring in an integrity management program and discuss the development of alert levels based on potential failure modes of the riser systems. The paper will further demonstrate how this process is key for an effective integrity management program for deepwater riser systems.


Author(s):  
Bo Li ◽  
Haonan Tian ◽  
Qingyang Jing ◽  
Yajun Wang ◽  
Xiaohui Li
Keyword(s):  

2020 ◽  
Author(s):  
Edwina Dhyani Danaparamita ◽  
Nadiroh . ◽  
Desy Safitri

The rapid growth of the tourism industry in Indonesia has encouraged innovation in the sector as each business competes to attract domestic and foreign tourists. At the same time, however, this growth is having a negative impact of environmental damage such as water pollution and soil pollution, and also producing a perceived community loss. One option is to reduce the negative impact of tourism is by encouraging the development of ecotourism activities. For example, nearby communities could be encouraged to participate in the management of mangrove conservation ecotourism areas. This study considers how such communities can work with local governments on these projects. This complements traditional beliefs within the Indonesian culture which held that ancestors entrust natural wealth to their descendants to be guarded and utilized wisely. Keywords: conservation, mangrove, sustainable tourism


Webology ◽  
2021 ◽  
Vol 18 (Special Issue 04) ◽  
pp. 268-277
Author(s):  
Normali na ◽  
Muhammad Hatta ◽  
Hafizia noor ◽  
Hamd ani

The research method is qualitative with phenomenological approach. The research design using one site involving Banjarmasin City in South Kalimantan, Indonesia. Data collection techniques used were content analysis, participatory observation and depth interviews. The analysis used in answering this research is a combination of various analytical methods to answer each of the objectives namely miles & Huberman analysis and Webbed Spider Model Analysis as the ultimate in formulating management of plastic waste through a leadership role. The results of this research found that the adaptation of environmentally sound habits in minimizing the production of plastics waste through local wisdom approaches and changing the people's mindset to live healtier. The purpose of writing this paper is to provide examples of new habits of healthy living by starting to reduce the use of plastic bags as the main source of waste generation that is not easily biodegradable in Banjarmasin City produced in every citi anywhere and is a major problem of environmental damage, including Banjarmasin City as a city of a thousand rivers, south Kalimantan Province. Effort to reduce the use of pastic bags began in stages, starting with modern retailers in the City of Banjarmasin. Through a leadership role based on local wisdom and a persuasive approach that is environmentally sound, it can provide solutions in current and future waste management. Result from this research is Banjramasin as the first City in Indonesia implemented regulation to reduction of plastic waste for modern retailers which are widely scattered throughout the City, sub-districts and villages. This is effective through regulation and direct approach to society. In the waste management that is carried out in the City of Banjarmasin includes waste reduction activities with ten activities and waste handling through five activities. As a substitute for these plastic bags, plastic bag producers are forced to use environmentally friendly plastic bags and / or purun baskets which are products of local wisdom of the people of South Kalimantan, Indonesia, all of these activities are carried out by involving the community by applying the rules without sanctions. Until this paper was written, there has never been a leader with leadership who has implemented a similar regulation as a direct effort from the role of a leader in reducing the use of plastic bags, where the use of plastic bags is the biggest contributor as a source of producing plastic waste.


2021 ◽  
Vol 12 (1) ◽  
pp. 1
Author(s):  
Deepthie Perera

Sri Lanka, under the British from the early 19th century to 1948, saw a rapid growth in urban areas and the emergence of metropolitan bourgeoisie. Increasing demand for housing was met through housing schemes and private houses on smaller plots. Previous colonials, the Portuguese and the Dutch, adapted and continued the traditional house forms where outdoor transitional spaces such as verandas and courtyards remained as an integral part responding to climate and socio-cultural needs. However, the British period saw the advent of two noteworthy types of housing—a smaller re-adapted traditional house and an imported version of an all-enclosed house. This study evaluates the shift in socio-spatial role of the outdoor transitional spaces of single-unit houses from pre-colonial time up to independence using graphical analysis of the plan form combined with interviews on use of space.


Author(s):  
Parthkumar Patel ◽  
H.R. Varia

Safe, convenient and timely transportation of goods and passengers is necessary for development of nation. After independence road traffic is increased manifold in India. Modal share of freight transport is shifted from Railway to roadways in India. Road infrastructures continuously increased from past few decades but there is still need for new roads to be build and more than three forth of the roads having mixed traffic plying on it. The impact of freight vehicles on highway traffic is enormous as they are moving with slow speeds. Nature of traffic flow is dependent on various traffic parameters such as speed, density, volume and travel time etc. As per ideal situation these traffic parameters should remain intact, but it is greatly affected by presence of heavy vehicle in mixed traffic due to Svehicles plying on two lane roads. Heavy vehicles affect the traffic flow because of their length and size and acceleration/deceleration characteristics.  This study is aimed to analyse the impact of heavy vehicles on traffic parameters.


Author(s):  
C. C. Osadebe ◽  
H. A. Quadri

The prevalence of flexible pavement deterioration in the country has been adduced largely by highway researchers to trucks or heavy vehicles carrying much in excess of permitted legal limits. This study investigated levels of deterioration of Abuja-Kaduna-Kano road (Northern region) and Port Harcourt-Enugu road (Southern region) caused by heavy vehicles through a 14 day traffic counts conducted at 5 strategic points each in the Northern and Southern regions. Traffic data generated were analyzed with AASHTO Design Guidelines (1993) to evaluate Equivalent Single Axle Loads (ESALs) and Vehicle Damage effects on the road. The Traffic Volume, Average Daily Traffic (ADT), and Heavy Vehicle per day (HV/day) were estimated to be 2,063,977; 147,427; and 12,246 respectively in the Northern region, while in the Southern region they were estimated to be 750,381; 53,670; and 20,951 respectively. Motorcycles, Passenger cars, Mini-buses/Pick-ups, and Heavy vehicles constitute 18.7%, 49.7%, 23.3% and 8.31% of the total traffic volume respectively in the Northern region while in the South they constitute 4.6%, 30.1%, 26.2% and 39.1% respectively. ESALs were estimated according to AASHTO Design Guidelines in the Northern and Southern regions as 547,730 and 836,208 respectively. An average Load Equivalency Factors (LEFs) of 3.43 and 3.02 were estimated for each heavy vehicle plying the Northern and Southern roads respectively and this could explain some failures (alligator cracks, potholes, depressions, linear or longitudinal cracks along the centre line amongst others) inherent on the road.


2014 ◽  
Vol 8 (1) ◽  
pp. 292-296
Author(s):  
Zhi-Guo Zhao ◽  
Min Chen ◽  
Nan Chen ◽  
Yong-Bing Zhao ◽  
Xin Chen

The lateral security of heavy vehicle in deteriorative weather is one of the main causes of accidents of vehicles on roads. Road safety has become a subject of great concern to institutions of higher education and scientific research institutions. There are important theoretical and practical significances to explore applicable and effective lateral safety warning methods of heavy vehicles. One of the purposes of this paper is to provide a good theoretical basis for the core technology of heavy vehicle safety features for our country's independent research and development. Aiming at the issue of lateral security of heavy vehicle for road conditions in deteriorative weather, this paper constructs the framework of the lateral security pre-warning system of heavy vehicles based on cooperative vehicle infrastructure. Moreover, it establishes vehicle lateral security statics model through analysis of the force of the car in the slope with section bending and states the parameters of vehicles for no rollover. The side slip is indexed to calculate critical speed of vehicles in a bend. This paper also analyzes the influence of road friction coefficient, the road gradient and the turning radius on the lateral security of the vehicle with critical speed on the asphalt pavement with surface conditions ranging from wet, dry, snowing or icy. The calculation results show that the bad weather road conditions, road friction coefficient and turning radius have obvious influence on the lateral security critical speed. Experimental results indicate that the critical speed error warning is within 4% and it meets the design requirements.


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