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Induction machines (IM) are considered work horse for industrial applications due to their rugged, reliable and inexpensive nature; however, their low power density restricts their use in volume and weight limited environments such as an aerospace, traction and propulsion applications. Given recent advancements in additive manufacturing technologies, this paper presents opportunity to improve power density of induction machines by taking advantage of higher slot fill factor (SFF) (defined as ratio of bare copper area to slot area) is explored. Increase in SFF is achieved by deposition of copper in much more compact way than conventional manufacturing methods of winding in electrical machines. Thus a design tradeoff study for an induction motor with improved SFF is essential to identify and highlight the potentials of IM for high power density applications and is elaborated in this paper.

This is a errata for 2017-01-2520.

Vehicle manufacturers are suffering from increasing expenses for fixing software issues. This fact is mainly driving their desire to use mobile communication channels for doing Software Updates Over The Air (SOTA). Software updates today are typically done at vehicle service stations by connecting the vehicles’ electronic network via the On Board Diagnostic (OBD) interface to a service computer. These operations are done under the control of trained technicians. SOTA means that the update process must get handled by the driver. Two critical aspects need to get considered when doing SOTA at Electronic Brake Control (EBC) systems. Both will determine the acceptance of SOTA by legal authorities and by the passengers: The safety and security of the vehicle The availability of the vehicle for the passengers The security aspect includes the necessity to protect the vehicle and the manufacturers IP from unwanted attacks.

Engine cooling module air flows depend on package components and vehicle front end geometry. For years, in the early stages of vehicle development, front end geometry air flows were determined from 3/8 scale models or retrofit of similar existing vehicles. As time to market has become much shorter, finite element modeling of air flows is the only tool available. This paper describes how finite element simulations of front end air flows can be run early in the development program independent of any specific engine cooling module configuration and then coupled with traditional one-dimensional component performance models to predict cooling module air flows. The CFD simulation thus replaces the previous scale model testing process. The CFD simulations are used to determine the two parameters that characterize the front end geometry flow resistance (recovery coefficient and internal loss coefficient).

For over 30 years, field research and laboratory testing has consistently demonstrated that proper utilization of a seat belt dramatically reduces the risk of occupant death or serious injury in motor vehicle crashes. The injury prevention benefits of seat belts require that they remain fastened during collisions. Federal Motor Vehicle Safety Standards and SAE Recommended Practices set forth seat belt requirements to ensure proper buckle performance in accident conditions. Numerous analytical and laboratory studies have investigated buckle inertial release properties. Studies have repeatedly demonstrated that current buckle designs have inertial release thresholds well above those believed to occur in real-world crashes. Nevertheless, inertial release theories persist. Various conceptual amplification theories, coupled with high magnitude accelerations measured on vehicle frame components are used as support for these release theories.

Aerodynamic had played a primary role in high performance car since the late 1960s, when introduction of the first inverted wings appeared in some formulas. Race car aerodynamic optimisation is one of the most important reason behind the car performance. Moreover, for high performance car using naturally aspired engine, car aerodynamic has a strong influence also on engine performance by its influence on the engine airbox. To improve engine performance, a detailed fluid dynamic analysis of the car/airbox interaction is highly recommended. To design an airbox geometry, a wide range of aspects must be considered because its geometry influences both car chassis design and whole car aerodynamic efficiency. To study the unsteady fluid dynamic phenomena inside an airbox, numerical approach could be considered as the best way to reach a complete integration between chassis, car aerodynamic design, and airbox design.

A compact and high performance electric motor, called the 3D motor and designed to achieve output torque density of 100 Nm/L, was developed for use on electric vehicles and hybrid electric vehicles. The motor adopts an axial flux configuration, consisting of a disk-shaped stator sandwiched between two disk-shaped rotors with permanent magnets. It also adopts 9-phase current with a fractional slot combination, both of which increase the torque density. The rated torque output of this high power-density motor is achieved by applying a hybrid cooling system comprising a water jacket on the outer case of the stator and oil dispersion into the air gaps. The mechanical strength of the rotors against centrifugal force and that of the stator against torque exertion were confirmed in mechanical experiments. Several measures such as flux barriers, a chamfered rotor rim, parallel windings, and radially laminated cores were adopted to suppress losses.

The Soft X-Ray Telescope (SXT) is an instrument on the International X-Ray Observatory (IXO). Its flight mirror assembly (FMA) has a single mirror configuration that includes a 3.3 m diameter and 0.93 m tall mirror assembly. It consists of 24 outer modules, 24 middle modules and 12 inner modules. Each module includes more than 200 mirror segments. There are a total of nearly 14, 000 mirror segments. The operating temperature requirement of the SXT FMA is 20°C. The spatial temperature gradient requirement between the FMA modules is ±1°C or smaller. The spatial temperature gradient requirement within a module is ±0.5°C. This paper presents thermal design considerations to meet these stringent thermal requirements.

Hydraulic power steering systems traditionally are sized in a straightforward manner with easily verifiable results. The source of power in conventional systems is an engine driven pump that is effectively a source of hydraulic flow. As energy consumption of auxiliary functions becomes significant, on-demand power sources are considered. Best typified by hydraulic pumps driven by electric motors, these on-demand sources are often power limited, and established sizing practices should be re-visited.

Piezoelectric self-sensing allows to measure frequency response functions of dynamical systems with one single piezoelectric element. This piezoceramics is used as actuator and sensor simultaneously. In this study, a model-based piezoelectric self-sensing technique is presented to obtain potential squealing frequencies of an automotive disc brake. The frequency-response function of the brake system is obtained during operation by measuring the current flowing through the piezoelectric element while the piezoelectric element is driven by a harmonic voltage signal with constant amplitude. The current flow is composed of the part which is required to drive the piezoelectric element as an actuator and a second part which is the sensor signal that is proportional to the vibration amplitude of the attached mechanical system. Typically the first part is dominant and the influence of the mechanical system is marginal.

Many engineers have been working to reduce brake noise in many ways for a long time. So far, a progress has been made in preventing and predicting brake noise. Nevertheless, there are some discrepancies of brake noise generation propensity between testing for the prototype and the production. As known in general, the reason for this unpredicted brake noise occurrence in production is partly due to the variation of the resonant frequency, material and the other unpredictable or unmanageable variations of the components in a brake system. In this paper, effects of chemical components and casting process of gray iron brake disc on its resonant frequency variation have been studied. Especially this paper is focused on the variation in material aspects and manufacturing parameters during disc casting in usual production condition. And their effects are investigated by the variation of out-of-plane modal resonant frequency.

Brake judder is about oscillations excited by brake application, which are generated in the contact area between brake pad and brake disc and are transmitted by the elements of the suspension to body and steering system. The driver perceives these perturbations as brake pedal pulsations, steering wheel rotational and body vibrations. The evaluation of a suspension concerning brake judder often takes place for the first time in road tests, since established simulation processes with a high significance concerning ride comfort are missing. At such a late moment necessary modifications in the development process are only hardly possible and very expensive. For avoiding brake judder a systematic development process is needed for brake and suspension. Each one can separately be improved in measurably borders so that their assembly is free of cold brake judder. The present paper shows appropriate test and simulation methods to achieve this.

Scope of the DRESS project is to research, develop and validate a distributed and redundant electrical steering system technology for an aircraft nose landing gear. The new system aims to: • reduce system weight at aircraft level, replacing the current hydraulic actuation system with an electric one. • improve aircraft safety, achieving higher system redundancy levels compared to the current technology capabilities. This paper presents an outline of different activities occurring in the DRESS project and also shows preliminary results of the new system performance.

The effectiveness of serial link articulated robots in aerospace drilling and fastening is largely limited by positional accuracy. Unguided production robotic systems are practically limited to +/-0.5mm, whereas the majority of aerospace applications call for tolerances in the +/-0.25mm range. The precision with which holes are placed on an aircraft structure is affected by two main criteria; the volumetric accuracy of the positioner, and how the system is affected when an external load is applied. Production use and testing of off-the-shelf robots has highlighted the major contributor to reduced stiffness and accuracy as being error ahead of the joint position feedback such as backlash and belt stretch. These factors affect the omni-directional repeatability, thus limiting accuracy, and also contribute to deflection of the tool point when process forces are applied.

Patents granted recently to Mr. Rode have changed the industry capability to adjust and verify wheel-end bearings on trucks. Until now it was believed1 that there was nothing available to confirm or verify the most desirable settings of preload on these bearings. The new, breakthrough invention is a tool and spindle-locking nut that permit quick and accurate wheel bearing adjustment by utilizing direct reading force measurement. Bearings can be set to either SAE recommended preloads or specific endplay settings. The author has been working on bearing adjustment methods for industrial applications for over forty years, and considers these inventions to be his most important breakthrough for solving this elusive bearing adjustment problem. Consistent wheel bearing preload adjustment was not possible before, even though it was widely known to achieve the best wheel performance as noted in SAE specification J2535 and re-affirmed in 2006 by the SAE Truck and Bus Wheel Subcommittee.

The timing and associated levels of braking between initial brake pedal application and actual maximum braking at the wheels for a tractor-semitrailer are important parameters in understanding vehicle performance and response. This paper presents detailed brake timing information obtained from full scale instrumented testing of a tractor-semitrailer under various conditions of load and speed. Brake timing at steer, drive and semitrailer brake positions is analyzed for each of the tested conditions. The study further seeks to compare the full scale test data to predicted response from detailed heavy truck computer vehicle dynamics simulation models available in commercial software packages in order to validate the model's brake timing parameters. The brake timing data was collected during several days of full scale instrumented testing of a tractor-semitrailer performed at the Transportation Research Center, in East Liberty, Ohio.

The last decades have shown extensive efforts on the investigation of automotive disk brake squeal. The origin of brake squeal is seen in self-excited vibrations, caused by the friction forces transferring energy from the rotating disk into the brake system. Based on a very simple model, Popp et al. described in 2002 the conditions for positive work of the friction forces (i.e. excitation of squeal), which depends on the phase shift between the in-plane motion (with respect to the disk) of the brake pad and the friction forces. Experiments on active manipulation of this phase shift using pads with integrated piezoceramic actuators, performed by von Wagner et al. in 2004, resulted in successful suppression of disk brake squeal. The authors of the present paper used a variety of models for the investigation of the origin of the excitation mechanism by observing phase relations between the friction forces and the vibrations of the pads.

Extenics is a new cross discipline to study rules and methods of solving contradictory problems in the real world. The basic concepts and theoretical frame of extenics are briefly introduced in this paper. Based on the merit of extenics, the extension evaluation method was applied to evaluate the brake materials according to a five-grade criterion established in this study. Considering the results computed by the original and simplified models, the similar conclusions were made: all four brake samples, marked A - D, were evaluated in the first grade based on the calculated dependence degrees, and sample B was judged as the best performing friction material with the highest dependence degree and the lowest wear rate.

This paper summarizes results from the author's work on friction in dry sliding contacts in the presence of vibration. A number of idealized models of smooth and rough contacts are examined. It is shown that vibration can cause up to a 10% reduction in average friction even with continuous contact. A larger reduction in friction occurs when there is intermittent contact loss. This is found to be true for both elastic and plastic contacts, and for adhesive and plowing mechanisms of friction. The results of this work are compared and validated with measurements from experiments. The results presented are fundamental, but applicable to machine components with contacts including brake systems.

Manual drilling and Lockbolt installation in carbon fiber structures is a labor intensive process. To reduce man hour requirements while concurrently improving throughput and process quality levels BROETJE-Automation developed a gantry positioning system with high performance multi-function end effectors for this application. This paper presents a unique solution featuring fully automated drilling and Lockbolt installation (inclusive of automated collar installation) for the vertical tail plane (vertical stabilizer) of large commercial aircraft. A flexible and reconfigurable assembly jig facilitates high access of the end effectors and increases the equipment efficiency. The described system fulfils the demand for affordable yet flexible precision manufacturing with the capacity to handle different aircraft model panels within the work envelope.