This SAE Aerospace Information Report (AIR) covers the design parameters for various methods of humidification applicable to aircraft, the physiological aspects of low humidities, the possible benefits of controlling cabin humidity, the penalties associated with humidification, and the problems which must be solved for practical aircraft humidification systems. The design information is applicable to commercial and military aircraft. The physiological aspects cover all aircraft environmental control applications.
Abstract Globalization has intensively driven focus of car manufacturers on comfort and ergonomics. Luxuries are becoming essential features of product mix. Customer’s expectations and desires are changing because of cut throat competition and increasing variety of options. In order to sustain in marketplace, OEM has to be competitive while providing features and options with appropriate quality. Vigorously changing dimensions and definitions of comfort level, luxury and aesthetics has driven the intense focus of OEM’s on customer touch points, customer touch points are those components of vehicle which customer accesses while driving the vehicle and they play vital role in generating drive feel of vehicle. Customer’s drive feel about the vehicle is most complex and critical factor and is of subjective nature. Now days drive feel is an important aspect of product differentiation. Gear shift feel is very crucial touch point in overall drive feel of vehicle.
This SAE Recommended Practice describes methods for determining total and specular reflectance for mirrors with flat and curved surfaces and a method for determining diffuse reflectance and haze for mirrors with flat surfaces.
The design and location of rear viewing mirrors or systems, and the presentation of the rear view to the driver can be best achieved if the designer and the engineer have adequate references available on the physiological functions of head and eye movements and on the perceptual capabilities of the human visual system. The following information and charts are provided for this purpose. For more complete information of the relationship of vision to forward vision, see SAE SP-279.
This document recommends criteria for a system designed to manage and communicate information via data link to support flight operations.
This document recommends criteria for Airborne Windshear Systems, including operational objectives, characteristics and functional requirements. The recommendations of the document apply to transport aircraft, and describe the operational objectives of windshear alerting systems, situational displays, guidance systems and avoidance/detection systems.
Elicitation Practices That Can Decrease Vulnerability to Off-Nominal Behaviors: Lessons from using the Causal Component Model
Abstract When specifying an embedded system-to-be, a key consideration is how the embedded system will interact with its operating environment. Of particular concern is the system's vulnerability to Off-Nominal Behaviors (ONB) from human interaction. ONB vulnerability can result in human operators placing the system in an undesired state through an unforeseen sequence of events. This, in turn, can have an adverse effect on the system’s quality. Reducing ONB vulnerability can be challenging because human behavior can be unpredictable and stakeholders have a natural tendency to assume the system will be used in a predictable, nominal, manner. One approach to reducing ONB vulnerability is to specify the system as "fool-proof" as possible, during the requirements phase, where access to domain experts is at its most convenient.
Advanced Hydraulic Systems for Active Vibration Damping and Forklift Function to Improve Operator Comfort and Machine Productivity of Next Generation of Skid Steer Loaders
Abstract Mobile Earth Moving Machinery like Skid-steer loaders have tight turning radius in limited spaces due to a short wheelbase which prevents the use of suspensions in these vehicles. The absence of a suspension system exposes the vehicle to ground vibrations of high magnitude and low frequency. Vibrations reduce operator comfort, productivity and life of components. Along with vibrations, the machine productivity is also hampered by material spillage which is caused by the tilting of the bucket due to the extension of the boom. The first part of the paper focuses on vibration damping. The chassis’ vibrations are reduced by the use of an active suspension element which is the hydraulic boom cylinder which is equivalent to a spring-damper. With this objective, a linear model for the skid steer loader is developed and a state feedback control law is implemented.
Abstract The noise generated by the flow of air past a transport truck is a key design factor for the manufacturers of these vehicles as the sound levels in the cabin are a significant component of driver comfort. This paper describes a collaboration between Volvo GTT and the National Research Council Canada to measure the in-cabin aeroacoustics of a full-scale cab-over tractor in the NRC 9 m Wind Tunnel. Acoustic instrumentation was installed inside the tractor to record cabin noise levels and externally to acquire tunnel background noise data. Using a microphone mounted on the driver’s-side tunnel wall as a reference to remove variations in background noise levels between data points, differences in cabin noise levels were able to be detected when comparing the tractor with different configurations. The good repeatability of the data allowed for differences of as little as 0.5 dB to be measured.
Abstract It is well known that the ride quality of trucks is much harsher than that of automobiles. Additionally, truck drivers typically drive trucks for much longer duration than automobile drivers. These two factors contribute to the fatigue that a truck driver typically experiences during long haul deliveries. Fatigue reduces driver alertness and increases reaction times, increasing the possibility of an accident. One may conclude that better ride quality contributes to safer operation. The secondary suspensions of a tractor have been an area of particular interest because of the considerable ride comfort improvements they provide. A gap exists in the current engineering domain of an easily configurable high fidelity low computational cost simulation tool to analyze the ride of a tractor semi-trailer. For a preliminary design study, a 15 d.o.f. model of the tractor semi-trailer was developed to simulate in the Matlab/Simulink environment.
Abstract This research is based on the Controller Area Network (CAN) bus, and briefly analyzed its communication protocol with reference to the layered model of Open System Interconnect Reference Model (OSI). Subsequently, a data acquisition system was designed and developed including a Vehicle Communication Interface (VCI) and a laptop. After the overall architecture was built, the communication mechanism of the VCI was studied. Furthermore, the lap top app was built using the layered design followed by the implementation of a scheme for data collection and experimentation involving the test driving of a real car on road. Finally, the driving style was identified by means of fuzzy reasoning and solving ambiguity based on fuzzy theory; via training the acceleration sample and forecast using the excellent learning and generalization ability of Support Vector Machine (SVM) for high-dimensional, finite samples.
Abstract Gesture control has been increasingly applied to automotive industry to reduce the distraction caused by in-vehicle interactions to the primary task of driving. The aim of this study is to find out if gestures can reasonably be used to control in-car devices. Since there exists a big cultural difference of gesture between different countries because of its particularity, a set of gestures which support intuitive human-machine interaction in an automotive environment is searched. The results show a gesture dictionary for a variety of on-board functions, which conforms to Chinese drivers’ driving habits. Furthermore, this paper also describes a driving simulator test to evaluate the usability of gesture from different aspects including the effectiveness, efficiency, satisfaction, memorability and security. Static driving simulator is considered as an excellent environment for the in-car secondary task as its high safety level, repeatability and reliability.
Abstract Based on the emergency lane change cases extracted from the China naturalistic driving data, the driving steering behavior divides into three phases: collision avoidance, lateral movement and steering stabilization. Using the steering primitive fitting by Gaussian function, the distribution of the duration time, the relationship between steering wheel rate and deflection were analyzed in three phases. It is shown that the steering behavior essentially is composed of steering primitives during the emergency lane-change. However, the combination of the steering primitives is different according to the specific steering constraints in three phases. In the collision avoidance phase, a single steering primitive with high peak is used for the fast steering; in the lateral movement and stabilization phase, a combination of two or even more steering primitives is built to a more accurate steering.
Air Conditioning Service Procedures for Heavy duty and Off-Highway work Machines using R-134a refrigerant
This recommended practice provides technicians with safe and efficient techniques and general equipment recommendations for servicing Mobile Air Conditioning (MAC) systems in heavy duty and off-highway work machines. Presently, R-134a is the only approved refrigerant for use in mobile heavy duty and off-highway equipment and therefore this document primarily covers the servicing of R-134a systems. Since the technician may encounter other refrigerants a brief explanation on the identification safe handling of each refrigerant will be introduced.
The purpose of this Aerospace Information Report (AIR) is to provide guidelines for the selection and design of airborne liquid cooling systems. This publication is applicable to liquid cooling systems of the closed loop type and the expendable coolant type in which the primary function is transporting of heat from its source to a heat sink. Most liquid cooling system applications are oriented toward the cooling of electronics. Liquid cooling techniques, heat sinks, design features, selection of coolants, corrosion control, and servicing requirements for these systems are presented. Information on vapor compression refrigeration systems, which are a type of cooling system, is found in Reference 1.
This document provides guidance for laser operators and aviation authorities to determine the performance criteria that laser hazard control measures shall meet for the operation of an outdoor laser system in navigable airspace. The document does not cover systems intended to deliberately aim and or track lasers at aircraft such as FAA approved purposes, including visual warning systems, search and rescue, etc. Aircraft operations to be protected include all types that can be reasonably expected to operate in the affected area, which are traveling at speeds and altitudes defined in the Performance/Functional Requirements section. This document does not address all possible aircraft operations, (e.g., the operation of stealth, high-speed (> Mach 1), unmanned aircraft systems, aircraft above 60 000 feet MSL, etc.), including aircraft operating under a waiver from FAA regulations.
Special report: Lightweighting Uncovering the next actions in the industry's grand mass-reduction campaign. CAE's next leap forward With 3D simulations skyrocketing, engineers are looking forward to highly-optimized toolsets to keep pace with complexity. SAE Convergence 2016 Preview Meet the disruptors, network with peers and learn about the latest tech solutions that are rapidly changing the auto industry. "Military-grade" aluminum Jaguar, Exa say simulation to eliminate prototypes by 2020 OEMs expand testing of FEV variable-compression ratio engine Growth of FCVs and EVs tied to infrastructure Bolt EV seat design cuts weight, delights tall passengers Rolls-Royce reveals a Vision of its future Volvo bets on new PowerPulse, not 48V, to attack turbodiesel 'lag' SEAT to spearhead VW's new platform and 48V technology Dr. Jay Baron of CAR discusses vehicle lightweighting and predicts the outcome of the crucial CAFE mid-term review.
Location of Crew and Passenger Oxygen Masks, Portable Oxygen System, and Protective Breathing Equipment
Various emergency situations may require the dispensing of oxygen to all occupants of aircraft during flight. During an emergency event, depending on the aircraft operational flight capability, all cabin occupants must be serviced by a mask presentation system connected to an operational oxygen source. Several regulations specify the functional characteristics and requirements of the oxygen systems for aircraft in support of different missions. These should be referred to for the exact functional performance requirements. It is not the intent of this document to ensure conformance with these regulations, but only to recommend general concepts for the location of the oxygen masks and oxygen system outlets for proper accessibility by the aircraft occupants, whether cabin occupants or crew members. Different requirements may apply when the mission of the pressurized aircraft or the operational altitude of the aircraft is not in excess of FL250.
This document describes how the program achieves its objective: to educate and train currently qualified commercial pilots with multi-engine and instrument ratings for First Officer and eventually Captain positions with the regional and/or the major airlines. This document provides an overview of a selection process, an academic curriculum, and a flight training program which will develop industry-recognized competencies and instill the knowledge, skills and attitudes known as professional standards.
Technology of an Emotional Engine Sound Designing for Active Sound Control Using Order Balance and Musical Instrument Sound
Abstract This paper discusses approaches to emotionally improve the driving sound based on Active Sound Design (ASD). In the first step, target sound design methods are suggested in order to represent the vehicle’s concept and brand image via a driving sound. In this method, formant filter and musical chords are applied to the target sound synthesis. In the second step, a technique to make a target sound realistic in ASD system is discussed, which enables to stimulate the customers' emotion. In this technique, the process to simulate a musical instrument sound for a vivid driving sound and synthesize the sound with FIR filter is studied. Finally, the improved driving sound is demonstrated in ASD system.
Safety Considerations of Carry-On Baggage Relating to the Emergency Evacuation of Transport Category Aircraft
This SAE Aerospace Recommended Practice (ARP) provides information and recommended guidelines for handling carry-on baggage prior to emergencies and during the emergency evacuation of transport category aircraft. Recommendations are provided on limiting the size, amount, and weight of carry-on baggage brought into the cabin, improved stowage of carry-on baggage to minimize hazards to passengers in flight and during emergency evacuations, and procedures to ensure carry-on baggage is not removed during an emergency evacuation.
This specification is intended to be used as a general standard for industry use for design and construction of air transport galley equipment and inflight food service systems.
The standard would include requirements for HSI management [planning, execution, coordination (internal and external) documentation, administration and quality control], including collaboration among HSI domains, coordination between HSI and other disciplines to optimize total system performance, optimize human performance, and minimize personnel-driven risks and customer ownership costs.
Abstract The development of suspension systems has seen substantial improvements in the last years due to the use of variable dampers. Furthermore, the efficiency increase in the subsystems within the automotive chassis has led to the use of regenerative solutions, in which electric machines can be employed as generators to recover part of the energy otherwise dissipated. However, the harvesting capability of regenerative suspensions is often limited by friction and inertial phenomena. The former ones waste mechanical energy into heat, while the latter ones hamper the shock absorption by locking the suspension when subject to dynamic excitation. Besides a suitable design and sizing of components, recent research works highlight the use of the so-called motion rectifier to improve energy recovery by constraining the motion of the electric motor to a single sense of rotation.
Target setting and structural design of an EPS-in-the-Loop test bench for steering feeling simulation
Abstract The adoption of Electrical Power Steering (EPS) systems has greatly opened up the possibilities to control the steering wheel torque, which is a critical parameter in the subjective and objective evaluation of a new vehicle. Therefore, the tuning of the EPS controller is not only becoming increasing complicated, containing dozens of parameters and maps, but it is crucial in defining the basic DNA of the steering feeling characteristics. The largely subjective nature of the steering feeling assessment means that EPS tuning consists primarily of subjective tests on running prototypes. On account of that, this paper presents an alternative test bench for steering feeling simulation and evaluation. It combines a static driving simulator with a physical EPS assisted steering rack. The end goal is to more accurately reproduce the tactile feedback to the driver by including a physical hardware in lieu of complicated and difficult to obtain software models.
Abstract With motor and reduction mechanism applied to Electric Power Steering (short for EPS) system of automobile, the frictional loss torque of steering system is increased. The common friction compensation control through the sign function of angular velocity or the saturation function of angular velocity is conducted to reduce the frictional loss torque of steering system. However, when the motor used in steering system generates assist torque based on the common friction compensation control, the longitudinal intercepts of steering torque change obviously at different steering wheel angles. The driver will get different frictional loss torque of steering system at different steering wheel angle. The information of steering torque contains the change of steering reaction torque and the frictional loss torque of steering system, so the change of frictional loss torque can cause the fuzzy of road feeling.
Abstract This study investigated driver glances while engaging in infotainment tasks in a stationary vehicle while surrogate driving: watching a driving video recorded from a driver’s viewpoint and projected on a large screen, performing a lane-tracking task, and performing the Tactile Detection Response Task (TDRT) to measure attentional effects of secondary tasks on event detection and response. Twenty-four participants were seated in a 2014 Toyota Corolla production vehicle with the navigation system option. They performed the lane-tracking task using the vehicle’s steering wheel, fitted with a laser pointer to indicate wheel movement on the driving video. Participants simultaneously performed the TDRT and a variety of infotainment tasks, including Manual and Mixed-Mode versions of Destination Entry and Cancel, Contact Dialing, Radio Tuning, Radio Preset selection, and other Manual tasks. Participants also completed the 0-and 1-Back pure auditory-vocal tasks.
Observed Differences in Lane Departure Warning Responses during Single-Task and Dual-Task Driving: A Secondary Analysis of Field Driving Data
Abstract Advanced driver assistance systems (ADAS) are an increasingly common feature of modern vehicles. The influence of such systems on driver behavior, particularly in regards to the effects of intermittent warning systems, is sparsely studied to date. This paper examines dynamic changes in physiological and operational behavior during lane departure warnings (LDW) in two commercial automotive systems utilizing on-road data. Alerts from the systems, one using auditory and the other haptic LDWs, were monitored during highway driving conditions. LDW events were monitored during periods of single-task driving and dual-task driving. Dual-task periods consisted of the driver interacting with the vehicle’s factory infotainment system or a smartphone to perform secondary visual-manual (e.g., radio tuning, contact dialing, etc.) or auditory-vocal (e.g. destination address entry, contact dialing, etc.) tasks.
Estimation of Driver Workload Based on a Model of Accelerator Pedal Control While Controlling Vehicle Velocity
Abstract In driver-focused vehicle development, driver workload is generally evaluated subjectively, with physiological, psychological, and behavioral indexes used to quantify and substantiate the subjective rating. In contrast, a model of driver behavior expresses the driver’s behavioral characteristics which make it possible to estimate how the driver will incorporate information into vehicle operation. Therefore, it is presumed to be capable of estimating the internal state of a driver. Conventionally, a model of driver behavior related to pedal operation has been used for evaluating the driver’s habits and the acceptability of various types of support devices. However, it has not been used for estimating driver workload related to pedal operation. To examine driver workload, this study divided pedal operation magnitude into two components: a learning/judgment component and a correcting component for prediction errors. A method was devised of separating these two components.
Abstract In China there are many mixed driving roads which cause a lot of safety problems between vehicles and pedalcyclists. Research on driver behavior under risk scenarios with pedalcyclist is relatively few. In this paper driver brake parameters under naturalistic driving are studied and pedalcyclists include bicyclist, tricyclist, electric bicyclist and motorcyclist. Brake reaction time and maximum brake jerk are used to evaluate driver brake reaction speed. Average deceleration is used to evaluate the effect of driver brake operation. Maximum deceleration is used to evaluate driver braking ability. Driver behaviors collected in China are classified and risk scenarios with pedalcyclist are obtained. Driver brake parameters are extracted and statistical characteristics of driver brake parameters are obtained. Influence factors are analyzed with univariate ANOVA and regression analysis.