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1 – 10 of 29Sutapa Mondal and Arup Kumar Nandi
The purpose of this paper is to design an improved parallel regenerative braking system (IPRBS) for electric vehicles (EVs) that increases energy recovery with a constant brake…
Abstract
Purpose
The purpose of this paper is to design an improved parallel regenerative braking system (IPRBS) for electric vehicles (EVs) that increases energy recovery with a constant brake pedal feel (BPF).
Design/methodology/approach
The conventional hydro-mechanical braking system is redesigned by incorporating a reversing linear solenoid (RLS) and allowed to work in parallel with a regenerative brake. A braking algorithm is proposed, and correspondingly, a control system is designed for the IPRBS for its proper functioning, and a mathematical model is formulated considering vehicle drive during braking. The effectiveness of IPRBS is studied by analyzing two aspects of regenerative braking (BPF and regenerative efficiency) and the impact of regenerative braking contribution to range extension and energy consumption reduction under European Union Urban Driving Cycle (ECE).
Findings
IPRBS is found to maintain a constant BPF in terms of deceleration rate vs pedal displacement during the entire braking period irrespective of speed change and deceleration rate. The regenerative ratio of IPRBS is found to be high compared with conventional parallel regenerative braking, but it is quite the same at high deceleration.
Originality/value
A constant BPF is achieved by introducing an RLS between the input pushrod and booster input rod with appropriate controller design. Comparative analysis of energy regenerated under different regenerative conditions establishes the originality of IPRBS. An average contribution ratio to energy consumption reduction and driving range extension of IPRBS in ECE are obtained as 18.38 and 22.76, respectively.
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Vinoth Kumar K., Loganathan T.G. and Jagadeesh G.
The Purpose of this study is to prove the possibility of developing low cost mechanical anti – lock braking system (ABS) for the passenger’s safety.
Abstract
Purpose
The Purpose of this study is to prove the possibility of developing low cost mechanical anti – lock braking system (ABS) for the passenger’s safety.
Design/methodology/approach
The design methodology of the proposed newer mechanical ABS comprises of two units, namely, the braking unit and wheel lock prevention unit. The braking unit actuates the wheel stopping as and when the driver applies the brake, whereas the wheel lock prevention unit initiates wheel release to prevent locking and subsequent slip/skidding. The brake pedal with master cylinder assembly and double-arm cylinder forms the braking unit, brake pad cylinder, movable brake pad, solenoid valve and dynamo forms the wheel lock prevention unit. The dynamo coupled with the rotor energises/de-energises the solenoid values to direct airflow for applying brake and release it, which makes the system less energy-dependent.
Findings
The braking unit aids in vehicle stops, by locking the disc with the brake pad actuated by a double-arm cylinder. The dynamo energises the solenoid valve to activate the brake pad cylinder piston for applying the brake on the disc. Instantaneously, on applying the brake the dynamo de-energises the solenoid to divert the pneumatic flow for retracting the brake pad thereby minimizing the braking torque. The baking torque reduction revives the wheel rotating and prevents slip/skidding.
Originality/value
Mechanical ABS preventing wheel lock by torque reduction principle is a novel method that has not been evolved so far. The system was designed with repair/replacement of the parts and subcomponents to support higher affordability on safety grounds.
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Wei Jiang, Ray C. Chang, Ning Yang and Ying Xu
The purpose of this paper is to present a comparative study of flight circumstances, dynamic stability characteristics and controllability for two transport aircraft in severe…
Abstract
Purpose
The purpose of this paper is to present a comparative study of flight circumstances, dynamic stability characteristics and controllability for two transport aircraft in severe atmospheric turbulence at transonic cruise flight for the purpose to obtain the prevention concepts of injuries to passengers and crew members for pilot training in International Air Transport Association (IATA) – Loss of Control In-flight (LOC-I) program.
Design/methodology/approach
A twin-jet and a four-jet transport aircraft encountering severe atmospheric turbulence are the study cases for this paper. The nonlinear unsteady aerodynamic models are established through flight data mining and the fuzzy-logic modeling technique based on the flight data of flight data recorder. This method can be adopted to examine the influence of horizontal wind shear and crosswind on loss of control, dynamic stability characteristics and controllability for transport aircraft in different weights and different sizes in tracking aviation safety of existing different types of aircraft.
Findings
The horizontal wind shear or crosswind before the turbulence encounter will easily induce rolling motion and then initiate the sudden plunging motion during the turbulence encounter. The roll rate will increase the oscillatory rolling motion during plunging motion, if the rolling damping is insufficient. The drop-off altitude will be enlarged by the oscillatory rolling motion during the sudden plunging motion.
Research limitations/implications
A lack of the measurement data of vertical wind speed sensor on board to verify the estimated values of damping term is one of the research limitations for this study. The fact or condition of being severe in sudden plunging motion can be judged through the analysis of oscillatory derivatives with both dynamic stability and damping terms.
Practical implications
The roll rate will increase the oscillatory rolling motion during plunging motion, if the rolling damping is insufficient. The drop-off altitude will be enlarged by the oscillatory rolling motion during the sudden plunging motion. The horizontal wind shear or crosswind before the turbulence encounter will easily induce rolling motion and then initiated the sudden plunging motion during the turbulence encounter. If the drift angle is large, to turn off the autopilot of yaw control first and stabilize the rudder by the pedal. When passing through the atmosphere turbulence area, the pilots do not need to amend the heading angle urgently.
Social implications
The flight safety prevention in avoidance of injuries for passengers and cabin crews is essential for the airlines. The horizontal wind shear or crosswind before the turbulence encounter will easily induce rolling motion and then initiated the sudden plunging motion during the turbulence encounter.
Originality/value
The flight safety prevention in avoidance of injuries for passengers and cabin crews is essential. The present assessment method is an innovation to examine the loss of control problems of aviation safety and promote the understanding of aerodynamic responses of the jet transport aircraft. It is expected to provide a valuable lecture for the international training courses for IATA – LOC-I program after this paper is being published.
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Lalit Narendra Patil, Hrishikesh P. Khairnar and S.G. Bhirud
Electric vehicles are well known for a silent and smooth drive; however, their presence on the road is difficult to identify for road users who may be subjected to certain…
Abstract
Purpose
Electric vehicles are well known for a silent and smooth drive; however, their presence on the road is difficult to identify for road users who may be subjected to certain incidences. Although electric vehicles are free from exhaust emission gases, the wear particles coming out from disc brakes are still unresolved issues. Therefore, the purpose of the present paper is to introduce a smart eco-friendly braking system that uses signal processing and integrated technologies to eventually build a comprehensive driver assistance system.
Design/methodology/approach
The parameters obstacle identification, driver drowsiness, driver alcohol situation and heart rate were all taken into account. A contactless brake blending system has been designed while upgrading a rapid response. The implemented state flow rule-based decision strategy validated with the outcomes of a novel experimental setup.
Findings
The drowsiness state of drivers was successfully identified for the proposed control map and set up vindicated with the improvement in stopping time, atmospheric environment and increase in vehicle active safety regime.
Originality/value
The present study adopted a unique approach and obtained a brake blending system for improved braking performance as well as overall safety enhancement with rapid control of the vehicle.
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Indranil Banik, Arup Kumar Nandi and Bittagopal Mondal
The paper aims to identify a suitable generic brake force distribution ratio (β) corresponding to optimal brake design attributes in a diminutive driving range, where road…
Abstract
Purpose
The paper aims to identify a suitable generic brake force distribution ratio (β) corresponding to optimal brake design attributes in a diminutive driving range, where road conditions do not exhibit excessive variations. This will intend for an appropriate allocation of brake force distribution (BFD) to provide dynamic stability to the vehicle during braking.
Design/methodology/approach
Two techniques are presented (with and without wheel slip) to satisfy both brake stability and performance while accommodating variations in load sharing and road friction coefficient. Based on parametric optimization of the design variables of hydraulic brake using evolutionary algorithm, taking into account both the laden and unladen circumstances simultaneously, this research develops an improved model for computing and simulating the BFD applied to commercial and passenger vehicles.
Findings
The optimal parameter values defining the braking system have been identified, resulting in effective β = 0.695 which enhances the brake forces at respective axles. Nominal slip of 3.42% is achieved with maximum deceleration of 5.72 m/s2 maintaining directional stability during braking. The results obtained from both the methodologies are juxtaposed and assessed governing the vehicle stability in straight line motion to prevent wheel lock.
Originality/value
Optimization results establish the practicality, efficacy and applicability of the proposed approaches. The findings provide valuable insights for the design and optimization of hydraulic drum brake systems in modern automobiles, which can lead to safer and more efficient braking systems.
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Joyce Shaffer and Freda Gonot-Schoupinsky
The purpose of this paper is to meet Dr Joyce Shaffer, PhD, ABPP, Clinical Associate Professor at the University of Washington.
Abstract
Purpose
The purpose of this paper is to meet Dr Joyce Shaffer, PhD, ABPP, Clinical Associate Professor at the University of Washington.
Design/methodology/approach
This case study is presented in two sections: a positive autoethnography written by Joyce Shaffer, followed by her answers to ten questions.
Findings
In this positive autoethnography, Shaffer shares her life story and reveals numerous mental health and positive aging recommendations and insights for us to reflect on.
Research limitations/implications
This is a personal narrative, albeit from someone who has been a clinical psychologist and active in the field of aging for many decades.
Practical implications
A pragmatic approach to aging is recommended. According to Shaffer, “those of us who can recognize the beat of the historical drummer can harvest the best of it and learn from the rest of it.”
Social implications
Positive aging has strong social implications. Shaffer considers that it is not only about maximizing our own physical, mental, emotional and social health but also about maximizing that of others, to make our world a better place for everyone.
Originality/value
Positive aging can be experienced despite adversity. As Shaffer says, “Adversity used for growth and healed by love is the answer.”
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Zhizhong Guo, Fei Liu, Yuze Shang, Zhe Li and Ping Qin
This research aims to present a novel cooperative control architecture designed specifically for roads with variations in height and curvature. The primary objective is to enhance…
Abstract
Purpose
This research aims to present a novel cooperative control architecture designed specifically for roads with variations in height and curvature. The primary objective is to enhance the longitudinal and lateral tracking accuracy of the vehicle.
Design/methodology/approach
In addressing the challenges posed by time-varying road information and vehicle dynamics parameters, a combination of model predictive control (MPC) and active disturbance rejection control (ADRC) is employed in this study. A coupled controller based on the authors’ model was developed by utilizing the capabilities of MPC and ADRC. Emphasis is placed on the ramifications of road undulations and changes in curvature concerning control effectiveness. Recognizing these factors as disturbances, measures are taken to offset their influences within the system. Load transfer due to variations in road parameters has been considered and integrated into the design of the authors’ synergistic architecture.
Findings
The framework's efficacy is validated through hardware-in-the-loop simulation. Experimental results show that the integrated controller is more robust than conventional MPC and PID controllers. Consequently, the integrated controller improves the vehicle's driving stability and safety.
Originality/value
The proposed coupled control strategy notably enhances vehicle stability and reduces slip concerns. A tailored model is introduced integrating a control strategy based on MPC and ADRC which takes into account vertical and longitudinal force variations and allowing it to effectively cope with complex scenarios and multifaceted constraints problems.
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Julian Waters-Lynch and Cameron Duff
The purpose of this study is to reflect on and analyse the sensory experiences related to the transition to remote work during the COVID-19 pandemic. The research seeks to…
Abstract
Purpose
The purpose of this study is to reflect on and analyse the sensory experiences related to the transition to remote work during the COVID-19 pandemic. The research seeks to understand how these experiences have influenced the integration of work practices into home and family life and the subsequent adaptations and embodied learning that arise in response.
Design/methodology/approach
The authors' research approach incorporates autoethnographic methods to explore the sensory, affective and emotional experiences of transitioning to remote work. The authors draw on principles of embodied learning, as influenced by Gilles Deleuze, and utilise a range of ethnographic tools including note-taking, audio memos, photography, shared conversations and written reflections to gather their data.
Findings
The study illuminates the ways bodies learn to accommodate the new organisational contexts that arise when the spaces, affects and forces of home and work intersect. It demonstrates how the integration of work into the private domain resulted in new affective and material arrangements, involving novel sensory experiences and substantial embodied learning.
Originality/value
This study provides a distinct, sensory-oriented perspective on the challenges and transformations of remote work practices amid the pandemic. By focussing on the affective resonances and embodied learning that emerge in this context, it contributes to the emerging discourse around post-lockdown work practices and remote work in general.
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Joëlle Hafsi and Louis Jacques Filion
Pierre Nelis joined a small group of artists working for a creative entrepreneur who had invented software to produce movies. He brought a great deal of marketing expertise to a…
Abstract
Pierre Nelis joined a small group of artists working for a creative entrepreneur who had invented software to produce movies. He brought a great deal of marketing expertise to a team of technology creators, and it was this that ultimately allowed the firm to sell its software to movie industry leaders throughout the world. The firm – Softimage – was bought by Microsoft, which hired Pierre Nelis to oversee the integration process, and later to develop new communications products. Nelis has an outstanding ability to identify the elements needed by a firm to become more effective, and this led him to set up a one-of-a-kind external facilitation programme that went on to become a model for many business growth support organizations throughout the world, but especially in North America and Europe.
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Amer Jazairy, Timo Pohjosenperä, Jaakko Sassali, Jari Juga and Robin von Haartman
This research examines what motivates professional truck drivers to engage in eco-driving by linking their self-reports with objective driving scores.
Abstract
Purpose
This research examines what motivates professional truck drivers to engage in eco-driving by linking their self-reports with objective driving scores.
Design/methodology/approach
Theory of Planned Behavior (TPB) is illustrated in an embedded, single-case study of a Finnish carrier with 17 of its truck drivers. Data are obtained through in-depth interviews with drivers, their fuel-efficiency scores generated by fleet telematics and a focus group session with the management.
Findings
Discrepancies between drivers’ intentions and eco-driving behaviors are illustrated in a two-by-two matrix that classifies drivers into four categories: ideal eco-drivers, wildcards, wannabes and non-eco-drivers. Attitudes, subjective norms and perceived behavioral control are examined for drivers within each category, revealing that drivers’ perceptions did not always align with the reality of their driving.
Research limitations/implications
This study strengthens the utility of TPB through data triangulation while also revealing the theory’s inherent limitations in elucidating the underlying causes of its three antecedents and their impact on the variance in driving behaviors.
Practical implications
Managerial insights are offered to fleet managers and eco-driving solution providers to stipulate the right conditions for drivers to enhance fuel-efficiency outcomes of transport fleets.
Originality/value
This is one of the first studies to give a voice to professional truck drivers about their daily eco-driving practice.
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