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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).

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).

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.

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.

To present the findings of the research on the use of concurrent engineering in the development of polymeric based composite automotive clutch pedal. It covers the use of various IT such as expert system, FEA, CAD, mould flow and rapid prototyping in order to carry out various activities such as material selection, total design, design analysis and mould flow analysis.

The work started with the conceptual design of an automotive composite clutch pedal. Various design guides related to composite materials were followed. The final concept of the composite clutch pedal is developed using Pro/Engineer solid modelling package. Design analysis was carried out using LUSAS to study the optimum pedal lever cross section and the optimum rib patterns in pedal lever. Mould flow analysis was investigated to predict the behaviour of materials inside the injection moulding machine and the results are compared with experimental values. Rapid prototyping models were developed based on two techniques namely 3D printer and stereolithography and they are compared in terms of quality, time and cost.

In this study, the integrated IT tools enable the designer to design and manufacture automotive an composite clutch pedal at higher quality and faster time compared to a metal counterpart. By adopting composite design guides, weight saving from implementing composite materials in the clutch pedal is achievable. It is found that an expert system for material selection enables designer to select the suitable composite material for the clutch pedal by considering various parameters such as strength, modulus, density, manufacturing and economic constraints. Rapid prototyping models enable the designer to communicate effectively their design to other parties early in the design process. Mould flow analysis is carried out to predict the behaviour of material inside the mould and to design the optimum moulding parameters such as fill time, fill temperature and gate location.

In this study, the originality lies in the integration of various IT tools in the development of composite clutch pedal. The designer is exposed to various design and manufacturing issues from the implementation of such approach early in the design process.

This paper aims to focus on the design, analysis and additive manufacturing (AM) with two different technologies of an accelerator pedal for the Formula Student 2014 edition to reduce the weight of the original pedal in aluminium and maintain a reasonable level of performance.

The new and the original accelerator pedals were modelled in a computer-aided design application, and three finite element simulations were performed for each manufacturing technology to evaluate three different driving scenarios. Later on, two physical prototypes were manufactured using two AM technologies: poly-jet and fused deposition modelling (FDM). With these physical prototypes, static tests were carried out to verify the computational simulations and to determine the fracture load, while dynamic tests, based on an input signal from a real racing scenario, were performed to ensure their technical viability.

Simulations with poly-jet and FDM printing material show that the new design presents a maximum deformation of 4.8 and 4.09 mm, respectively, under a nominal load of 150N. The results of the static tests with the poly-jet physical prototype showed a maximum displacement of 4.05 mm under a nominal load of 150N, while the ultimate load before fracture was 450N. The FDM prototype reached 3.98 mm under 150N and the ultimate load was 350N. Dynamic tests showed that both pedals were able to withstand four Formula Student “Endurance” events without failure.

This paper states that AM approach is a feasible and economically affordable solution in comparison to exiting solutions with metallic alloys and composite materials when designing and manufacturing accelerator pedal arms for Formula Student competition cars. According to these results, the present research argues that, from a technical point of view, the AM pedals stand at a reasonable level of performance in displacements and stresses. This study suggests that AM pedals could be a viable option that must be considered in professional competitive automobiles.

The purpose of this paper is to report on the use of a combination of selective laser sintering (SLS) and vacuum casting to create plastic composites made by additive manufacturing.

The research has been carried out by approaching a new concept of the final part consistent in a plastic component, where the main body is made by SLS and the internal long fibres for reinforcing are made by vacuum casting of high-resistance epoxy resin. The part is designed for optimal number and distribution of the internal fibres taking into account the target relative stiffness (N/mm*kg). The methodology is applied to a pedal clutch of a car which has been tested in an equipment for fatigue and durability, being compared to the correspondent design for injection moulding.

Research has proven that the approach introduces relevant improvement in mechanical properties of the base resin consistent in PA 3200GF (EOS), reinforced by internal long fibres of resin VG SP5. Experiments showed significant increase of stiffness in the pedal clutch made under this procedure, where the stiffness was 77 per cent higher than the conventional SLS part and only 11.7 per cent lower than the one made by injection moulding of PA 66 with 50 per cent fibreglass.

The developed method introduces an alternative procedure for increasing the mechanical properties of plastic parts developed in SLS. Optimal orientation and distribution of long fibres clearly achieves better mechanical properties at low cost.

In late 2009 Toyota became the subject of media and U.S. government scrutiny after multiple deaths and injuries were attributed to accidents resulting from the unintended and uncontrolled acceleration of its cars. Despite Toyota's voluntary recall of 4.2 million vehicles for floor mats that could jam the accelerator pedal and a later recall to increase the space between the gas pedal and the floor, the company insisted there was no underlying defect and defended itself against media reports and regulatory statements that said otherwise. As the crisis escalated, Toyota was further criticized for its unwillingness to share information from its data recorders about possible problems with electronic throttle controls and sticky accelerator pedals, as well as braking problems with the Prius. By the time Toyota Motor Company president Akio Toyoda apologized in his testimony to the U.S. Congress, Toyota's stock price had declined, in just over a month, by 20 percent---a $35 billion loss of market value.

Understand the strategic and reputational nature of crises Recognize the challenges of managing a crisis Learn the requirements for building trust in a crisis Understand the challenges of managing a crisis that may not be the company's fault Identify the strategic business problem in a crisis Understand how corporate structure may help or hinder effective crisis management Understand the media landscape and its impact on crisis management

The purpose of this study is to lead to an improvement in pilot-aircraft interaction. The goal of the performed tests is an assessment of haptic feedback, which mediates flight parameters to the pilot. Pedals indicate side-slip angle by vibrations, whereas a sliding element inside the control stick is able to continuously indicate both angles of attack and side-slip.

Haptic feedback applied on rudder pedals and control stick were tested on a flight simulator and flight tests in a couple of tasks. Pilot workload, readability of feedback and side-slip were then evaluated when the flight was turning.

As a useful instrument for aircraft control, haptic feedback was assessed. The feedback settings were then individually perceived, and haptic feedback slightly improved side-slip while turning in a flight test; however, the results are not statistically significant.

The tests provided promising results for human pilot performance. The training phase and personal settings of haptic feedback is an approach for improving the performance of human pilots.

The designed and tested device is a unique tool for improving pilot-aircraft interaction. This study brings valuable experiences from its flight simulator and in-flight tests.

The peer review history for this article is available at: https://publons.com/publon/10.1108/AEAT-12-2019-0265/

This paper aims to present the results of physical analysis that was conducted on Toyota's electronic engine control system including accelerator pedal position sensors (APPSs). The paper overviews the analyses and focuses on the discovery of tin whiskers found in the accelerator pedal assembly, which are an electrical failure concern.

Analytical techniques such as X‐ray fluorescence spectroscopy, scanning electron microscopy and energy dispersive spectroscopy are utilized to present a construction analysis of the APPS.

The use of a tin finish in the APPS is a cause for concern. Tin finishes are known to produce metal whiskers that are conductive and capable of creating unintended current leakage paths. In the analysis, a significant number of tin whiskers were found.

The methodology discussed in this paper can be implemented to inspect for tin whiskers in the APPSs.

The paper begins a construction analysis of different parts of the Toyota engine control module and APPSs and then moves on to highlight electronics design issues that can comprise the engine control system and cause unintended consequences.

To support the standardized evaluation of bicyclist automatic emergency braking (AEB) systems, test scenarios, test procedures and test system hardware and software tools have been investigated and developed by the Transportation Active Safety Institute (TASI) at Indiana University-Purdue University Indianapolis. This paper aims to focus on the development of test scenarios and bicyclist surrogate for evaluating vehicle–bicyclist AEB systems.

The harmonized general estimates system (GES)/FARS 2010-2011 crash data and TASI 110-car naturalistic driving data (NDD) are used to determine the crash geometries and environmental factors of crash scenarios including lighting conditions, vehicle speeds, bicyclist speeds, etc. A surrogate bicyclist including a bicycle rider and a bicycle surrogate is designed to match the visual and radar characteristics of bicyclists in the USA. A bicycle target is designed with both leg pedaling and wheel rotation to produce proper micro-Doppler features and generate realistic motion for camera-based AEB systems.

Based on the analysis of the harmonized GES/FARS crash data, five crash scenarios are recommended for performance testing of bicyclist AEB systems. Combined with TASI 110-car naturalistic driving data, the crash environmental factors including lighting conditions, obscuring objects, vehicle speed and bicyclist speed are determined. The surrogate bicyclist was designed to represent the visual and radar characteristics of the real bicyclists in the USA. The height of the bicycle rider mannequin is 173 cm, representing the weighted height of 50th percentile US male and female adults. The size and shape of the surrogate bicycle were determined as 26-inch wheel and mountain/road bicycle frame, respectively. Both leg pedaling motion and wheel rotation are suggested to produce proper micro-Doppler features and support the camera-based AEB systems.

The results have demonstrated that the developed scenarios, test procedures and bicyclist surrogate will provide effective objective methods and necessary hardware and software tools for the evaluation and validation of bicyclist AEB systems. This is crucial for the development of advanced driver assistance systems.

This paper presents the simulation results of a glass fiber reinforced PA 6,6 composite automotive clutch pedal. The analysis is carried out using Moldflow Plastics Insight (MPI) software to investigate the effects of increasing gate number from 1 to 2 on temperature and pressure. The results of temperature show that for single gate, the temperature was 291.3 °C and for double gate was 292.3 °C. Double gates mold induce higher temperature due to longer runner length. Both designs revealed different hot spots locations indicating probable areas of excess shear heating. The results of pressure (end of fill), for the single gate it was 61.31 MPa and for double gate was 60.73 MPa. Double gates mold reduce the required injection pressure as well as pressure variation, hence a lower volumetric shrinkage. Lower injection pressure produces lower shear rate and shear stress level.