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Vehicle model plays an important role during the development process of a new car chassis. There are 2 different ways to set up the vehicle mathematics model, one is set up based on understanding the system mechanism and the other is based on system identification technique. In this paper, the transfer functions of the vehicle at 100 km/h, including yaw rate to the steering angle and lateral acceleration to the steering angle, were identified. And then the transfer functions under other forward speed were derived through studying two degrees of freedom vehicle model equation. At last the identified model at different speed was used to analysis the stability of closed loop system from the classical control theory viewpoint.

The limits associated with the use of linear momentum procedures in impact speed predictions of two-car collisions are well established. A combined linear and rotational momentum procedure is introduced which makes it possible to compute the impact speeds of each vehicle based on the post crash data of only one vehicle, or based on only the angles rotated of each vehicle. The limitations of the combined procedure are discussed. A speed sensitivity analysis is presented which offers a methodology by which reasonably accurate speed predictions can be made. A number of actual computer applications are shown which demonstrates the usefulness and simplicity of the procedure presented.

A linear-shaped module based on Si-Ge alloys has been made for thermoelectric generation. The module is designed for generating electricity by exhaust heat of, e.g., plants, furnaces or automobiles. The module consists of 9 couples of p- and n-type Si-Ge alloy-based thermoelectric semiconductors. Carbon layers are made on both sides of the p- and n-type elements, and then the elements are electrically connected in series using Mo electrodes by blazing method. The size of the module is approximately 3.5 mm in width, 70 mm in length and 9.3 mm in height. Maximum power of the module was 2.0 W at a temperature difference of 509 K between the hot and cold sides of the module. A variation of generating power was measured for 150 modules. Maximum power of every module-block consisting of 10 modules was evaluated at a temperature difference of 400 K. The maximum power of the module-blocks was varied from 6.9 W to 8.7 W.

The loudness of powertrain noise generally increases with increasing rpm. In the case of ‘linear’ powertrain acceleration sound, the loudness versus time relationship is well described by a linear function. Two studies were conducted on powertrain linearity. The first used tests of similarity and preference to determine whether subjects could detect changes in linearity. The second used a subjective test of preference to investigate how subjects' preference varied with differing degrees of linearity. In both studies, stimulus sets were created by artificially introducing a controlled degree of non-linearity into a nominally linear powertrain sound. The results of the first study indicate that linearity is a phenomenon that naive subjects can readily detect, and that it has an effect on overall preference. Furthermore, the second study shows that preference is related to the magnitude and position of nonlinearities in the growth of loudness versus time during an acceleration run.

Successful implementation of temperature control is required in a variety of engineering applications. A method using the I-deas TMG finite volume thermal solver and MATLAB with the Control System Toolbox to characterize the control system performance of a thermal model was described by Saeger [1][2]; this paper describes an alternate approach to this method. The alternate method presented herein uses the TMG thermal solver to create linearized capacitance and conductance matrices of the thermal system. Then, MATLAB uses these matrices to create the frequency response curve using either matrix inversion or eigenvalue solution methods. Once the frequency response is generated, the MATLAB Control System Toolbox can be used to develop the control system.

Nowadays, (engine) downsizing using turbocharging appears as a major way for reducing fuel consumption. With this aim in view, the air actuators (throttle, Turbo WasteGate) control is needed for an efficient engine torque control especially to reduce pumping losses and to increase efficiency. This work proposes Nonlinear Model Predictive Control (NMPC) of the air actuators for turbocharged SI engines where the predictions are achieved by a neural model. The results obtained from a test bench of a Smart MCC engine show the real time applicability of the proposed method based on on-line linearization and the good control performances (good tracking, no overshoot) for various engine speeds.

The cylinder bore honing quality is an essential factor for a good engine performance and durability. A bad surface finish can result in an excessive lubricant oil consumption, high piston ring wear and scuffing occurrence. In this paper the most important characteristics of bore honing for cast iron cylinders and their influence in the combustion engine performance are described and discussed. Despite its importance, the bore honing is commonly undervalued due to various reasons including the difficulty of a practical but sufficient method of quality qualifying. Some honing commonly misunderstood concepts are detailed and SEM photographs of bore surface from both good and bad finish are presented. At the end of this paper it is also presented a recommendation for a practical evaluation method of honing quality.

In diesel engines, the cylinder liner is one of the places more susceptible to have cavitation. The cavitation process consists in creation (vaporization) of steam bubbles of liquid, and consequence brusque disappearance (condensation) of the same ones in the liquid. When this disappearance or implosion occurs next to the liner surface provokes erosion of the same one. This phenomenon basically occurs from the liner vibration or strangulation of the water flow, that they provoke high speed of the cooling fluid (equation of Bernoulli) [1]. Along a stream line: In this paper we will analyze how the liner vibration is related to the cavitation process, what is the source and how the easiest way to solve it. The methodology used was: Crank domain analysis, Abusive test, in order to accelerate the failure reproduction, Counter measure check, by vibration analysis & validation, by abusive test.

Motion is not only essential for interacting with the environment but also for its understanding. It has many facets which go beyond simply reaching a goal. Motion information often serves as the basis for inferring interrelationships between events, states and intentions of an acting entity. Observers can often identify persons from afar from their movement alone with only a low resolution view. In this connection it is important to identify dominant factors influencing this sensation. It would also be important to analyze how this understanding of motion relates to our primarily technological, cybernetic understanding of the structure of motion. This paper addresses some issues in this field. By emphasizing the compositional aspect of motion it extends the common technological structuring approach into another dimension. It does not offer a solution but serves as a basis for further discussions. At a first step, a linguistic approach is used for structuring complex motion.

Lining life numerical evaluation is getting increasingly popular. Through numerical simulation, the impacts on lining life due to design changes can be easily evaluated. The numerical approach usually predicts rotor temperature first, and then uses the lining wear versus rotor temperature data derived from physical testing to further assess lining life. Therefore, the success in predicting lining life largely relies on the accuracy of predicted rotor temperature as well as the lining wear versus rotor temperature data incorporated afterwards. In this paper, a 1-D rotor thermal model is presented, which intends to better predict rotor temperature while not dramatically increasing computational time. Furthermore, the inputs that would greatly affect simulation results are discussed. After that, two lining life evaluation examples, which employ the 1-D rotor thermal model, are presented. Finally, the applicability of lining wear versus rotor temperature data is discussed.

New technologies, such as electrified powertrain and autonomous driving solutions, are transforming the automotive industry in such a way that achieving vehicle level performance requirements demands an increasingly intensive and detailed system integration exercise. Validation of the braking system, critical to any vehicle level project, must evolve so that the ever-increasing requirements cascade is answered in a way that ensures the highest level of safety and performance as the industry moves toward a new frontier of features. To support this evolution of integration methodology, critical-to-performance components, such as brake pads, must undergo a transformation in how performance metrics are characterized, communicated, and documented.

Due to the dependence of friction on speed, pressure and temperature at the sliding interface, the same friction material exhibits varying friction characteristics in different brakes. For this reason, lining selection is typically carried out with design-intent brakes to capture the true behavior of friction materials. However, doing so necessitates prototype brakes and entails a long lead-time and high development costs. This paper explores the feasibility of conducting friction, fade, and wear tests on brake dynamometers with readily available surrogate brakes. Both analytical scaling principles and experimental results are presented and discussed.

Accurate measurements of brake friction materials are critical to understanding brake behaviors during testing. Current methods typically utilize a hand gauge (or a machine, in some cases) to sample various discrete points on the brake lining. This approach limits measurements to planar wear characteristics, taper and thickness, and excludes more complex measurements such as cupping. The limited number of points means that a single errant point measurement or the choice of point locations can have a large impact on the reported wear measurement. This paper will describe a method for utilizing a Coordinate Measurement Machine (CMM) fitted with a laser line scanning tool to generate a point cloud of data that can then be compared to an earlier measurement of the same piece or to a math model. This method produces thousands of data points which allows for more accurate volumetric wear calculations and color maps of the entire friction face.

Cavitation formation and development inside Diesel injector nozzles suffering from erosion damage has been investigated using enlarged transparent nozzle replicas and computational fluid dynamics (CFD) simulations. Cavitation erosion has been observed at different locations within the nozzle. These have included the top surface inside the nozzle hole next to its entry, the 3o'clock and 9c'clock hole side-inlets as well as at the needle seat area. Instantaneous and time-averaged high-speed CCD images of cavitation have verified that cavitation erosion sites are found in areas of cavitation bubble collapse. This has been further supported by CFD predictions obtained using the measured injection pressure and needle lift traces, both for the pilot and main injection events. The cavitating flow regimes associated with these erosion sites correspond to geometrically-induced hole cavitation, the string cavitation and the needle seat cavitation, respectively.

Radial lip type exclusion devices of various elastomers and configurations have been available to designers for decades. In recent years the steel-encased polyurethane rod scraper has become popular in the most difficult service environments of hydraulic cylinders on mobile equipment. An adaptation of this proven cylinder component is now extending lubrication intervals and life of critical linkage pins and bushings at oscillating pivot points on off-road construction and materials handling equipment. Its purpose is to exclude foreign material such as dirt, water, stones while retaining lubricants at the pin and bushing interface. The polyurethane material with its high tear strength and abrasion resistance extends seal life. Yet, its configuration allows for lubrication at longer maintenance intervals. Current information is that maintenance intervals have been reduced by ninety per cent.

On August 9, 1995, Environmental Protection Agency (EPA) established the Agency's service information regulations. These regulations, in part, required each Original Equipment Manufacturer (OEM) to either provide enhanced information to equipment and tool companies, or make its OEM-specific diagnostic tool available for purchase by aftermarket technicians. In 2001, Ford Motor Company developed a Microsoft Access database containing tested and verified vehicle data providing necessary module information from Ford Motor Company's specific diagnostic tools. The database was presented to the Equipment and Tool Institute (ETI) during the 2001 ETI Tech Week in Detroit. The format is being considered a recommended practice by ETI, and could be used by any OEM seeking a guideline for providing the necessary On-Board Diagnostics (OBD) protocol information.

Link-X Stability System (“Link-X”) is a control arm geometry that forces the control arms to both locate the tire and control the orientation of the chassis. This is achieved via crossing the control arms in the elevation view without having the control arms touch one another. Link-X inverts the overturning moment at each tire and applies the inverted moments to the chassis. In terms of traditional suspension analysis, this geometry creates a high yet completely stable roll center. Changing the vertical distances between the attachment points on the chassis or the spindle changes the amount of anti-roll generated. Anti-pitch is created by shifting the line of intersection of the control arm planes toward the vehicle's center of gravity.

As a means of controlling vehicle brake pressures for varying axle loads and/or vehicle decelerations, link-less brake deceleration sensing valves are being used in addition to fixed split point and link type load sensing proportioning valves. These valves are a means of optimizing the ratio of front-to-rear wheel retarding forces for the full range of vehicle loadings and decelerations thereby improving brake balance and vehicle stability. The object of this paper is to describe a link-less proportioning valve designed and developed for passenger cars and light trucks. Also, included are dynamic simulation and vehicle test results.

Kinematic synthesis of linkage mechanisms is in a new era. Interactive graphics has allowed designers to optimize solutions from among thousands and thousands of possibilities. This order of magnitude change in the kinematic synthesis method over the "thumb-tack and cardboard approach" is yet another excellent example of computer aided design. The LINCAGES © package demonstrates the modern approach to linkage design.

Faced with competitive environments, pressure to lower development costs and aggressive timelines engineers are not only increasingly adopting numerical simulation techniques but are also embracing design optimization schemes to augment their efforts. These techniques not only provide more understanding of the trade-offs but are also capable of proactively guiding the decision making process. However, design optimization and exploration tools have struggled to find complete acceptance and are typically underutilized in many applications; especially in situations where the algorithms have to compete with existing swift decision making processes. In this paper we demonstrate how the type of setup and algorithmic choice can have an influence and make optimization more lucrative in a new product development atmosphere. We also present some results from a design exploration activity, involving linkage and structural development, of an earth moving machine application.