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The accuracy of the injection rate meter based on W. Zeuch's method in the measurement of multiple injection rate and amount was calibrated using a small cam driven piston that is driven by an electric motor. For the pre- or early-injection, a sensor with a high sensitivity can be applied to measure the small pressure increase due to the small injection amount. In case of the multiple injection that has the post and/or late injection, a pressure sensor with a low sensitivity must cover not only the large pressure increase due to the main injection but also the small pressure increase due to the post and/or late injection because the output of the high sensitivity sensor is saturated after the main injection. So the linearity of the low sensitivity pressure sensor was calibrated with the cam driven piston prior to the experiment with the actual injection system.

The infrared technology for ACC sensors has reached a high standard up til now, but there are still problems with the detection of some vehicles. The most important factors for low detection ranges are bad weather conditions and the state of the vehicle. In order to guarantee a reliable function of the sensor it's important to know about the reflection properties of the vehicles. In this diploma work the influence of different factors on the reflection properties of vehicles was investigated. The parameters, which were taken into regard, are the colour of vehicles, the geometry of the vehicle rear, the viewing angle and the contamination of vehicles. The measurements were made with a modified LEICA ODIN 3 sensor with a very small aperture of the laser beam. This modified sensor was mounted in two axes rotatable, that the rear of the cars could be scanned, to measure the reflected radiation in every point of the rear.

Capacitance film thickness transducers have been developed which, when fitted into the cylinder liner of a diesel engine, enable the operating profile of the piston ring and the ring to liner oil film thickness to be obtained. The construction and operation of the gauges are described and some measurements are presented from the mid-stroke and top-dead-centre positions in a Caterpillar 1-G oil test engine.

This paper presents a method of measuring rolling element loads within large size ball bearings of four-point contact configuration. The rolling element loads are measured with an original method under five fastened conditions for a turntable bearing. The rolling element load distribution is obtained, and the results are compared to the computed loads and distributions.

In rear wheel drive vehicles, passenger perceived tonal noise is often generated by high frequency rotational vibrations of the transmission output shaft. This rotational vibration is excited by the transmission and couples with the dynamic and inertial properties of the driveline and suspension to generate forces through the suspension attachment locations. This paper demonstrates an approach which uses experimental techniques to measure the rotational dynamics of the output shaft and noise path analysis procedures to predict the vehicle system interaction and resulting vehicle noise contribution from this path. An evaluation of three rotational data acquisition techniques, a measurement technique used to characterize a vehicle's torsional acoustic sensitivity, and an application of mobility coupling to the torsional noise path is presented.

Precision spherical joints are widely employed in parallel mechanisms, but its rotation orientation and angle can not be known in its passive motion. Measurement of multi-dimensional angular displacement will be very of great significance in the prediction, feedback and control of motion errors of parallel mechanism. Based on the magnetic effect, a new method to identify the orientation and rotation angle with Hall sensors array matched by permanent magnet is proposed. The basic idea is embedding a permanent magnet(PM) in the ball head and several hall sensors are distributed in the ball socket. When the ball head carrying the permanent magnet rotates together, the Hall sensors array will detect the variation of magnetic induction intensity, and then the angle can be calculated by mathematics model.

Two structure-borne and two airborne paths were measured on 99 “identical” Isuzu RODEOs and 57 “identical” Isuzu pickup trucks. Significant effort was made to control measurement variability but not environmental (climate) variations. A record was kept of the tests of a reference vehicle over the variation of environmental factors. The frequency response functions (FRFs) of the reference vehicle varied by approximately 2-4 dB over the frequency range 0-500 Hz for the structure-borne paths and over 0-1000 Hz for the airborne paths due to measurement and environmental variations. The FRFs of the fleet varied by as much as 5-10 dB over the same frequency range. In this paper, the vehicle tests are described. The reference and the fleet data are shown in raw form. Reduced data and implications of the results are also discussed.

The two-load method is used to measure the transmission loss of thin panels in two different sized impedance tubes (3.49 cm and 10.16 cm). Samples were initially tested with a clamped boundary condition. This was followed by tests with an elastomer inserted between the tube and tested sample to adjust the boundary condition at the periphery. In all tests performed, the influence of the sample holding method could not be removed from the test. The measured transmission loss was compared to finite element simulation with good agreement for both impedance tubes. Additionally, the effect of a compliant boundary condition along the periphery of the sample was also validated via simulation.

A novel method of measuring cylinder gas temperature in an internal combustion engine cylinder is introduced. The physical basis for the technique is that the flow rate through an orifice is a function of the temperature of the gas flowing through the orifice. Using a pressure transducer in the cylinder, and another in a chamber connected to the cylinder via an orifice, it is shown how the cylinder temperature can be determined with useful sensitivity. In this paper the governing equations are derived, which show that the heat transfer characteristics of the chamber are critical to the performance of the system, and that isothermal or adiabatic conditions give the optimum performance. For a typical internal combustion engine, it is found that the pre-compression cylinder temperature is related to the chamber pressure late in the compression process with sensitivity of the order of 0.005 bar/K.

Conventional laboratory viscometric methods are not adequate to characterise the behaviour of multigrade oils in service, in that they take no account of the high shear rates occurring in running engines. A technique has been developed which permits the measurement of apparent viscosity in the crankshaft bearings of engines running under road conditions. The technique is to isolate a single bearing, provide it with its own oil feed and calibrate flow-rates through it under normal running conditions using single grade oils. Flow rates obtained with multigrade oils can then be converted to apparent viscosities, seen by the bearing under operating conditions. Results show that temporary viscosity loss due to shear is important even at moderate speeds (3000 rpm) in normal production engines. Shear breakdown characteristics of a range of different chemical types of VI Improvers have been compared.

This paper describes the development of a thin film rheometer able to measure the viscosity of lubricant films of the order of 200 μm thickness on flat, solid surfaces. The rheometer consists of a small cylinder mounted on a piezo bimorph which is divided electrically into two halves. When an AC voltage is applied to the one half of the piezo it causes the flat surface of the cylinder to oscillate in its own plane with an amplitude of a few microns. This motion produces an AC output from the other half of the piezo. The flat face of the cylinder is held parallel to an oily test surface and the latter is supported on a micrometer stage so that the gap between the two surfaces can be adjusted. As the gap is narrowed the oil film dampens the sinusoidal motion of the cylinder and the extent of this damping can be used to determine the viscosity of the oil film between the surfaces.

In this paper the fuel path of a sequentially injected gasoline engine is discussed. Since a fraction of the injected fuel suffers a delay due to the wall-wetting phenomenon, in transient phases a significant deviation of the air-to-fuel ratio from its setpoint can arise. The amount of fuel on the manifold wall and its rate of evaporation cannot be measured directly. Therefore, the effects of the wall-wetting on exhaust lambda and engine torque have to be considered for the identification of the dynamics. The dynamics of the exhaust-gas-oxygen (EGO) sensor is not negligible for the interpretation of the lambda measurement. Since both the dynamics and the statics of a ZrO2 Sensor are very nonlinear, a normal EGO-sensor is not suitable for these investigations. On the other hand, the engine torque is a good measure for the cylinder lambda when all other effects which lead to torque changes can be eliminated.

Currently in the automotive industry it is indispensable the evolution of technology applied in the design and manufacturing of components, either for a specific performance improvement or even as part of a cost reduction plan. For these main reasons, it has been constantly invested in methods that may help engineers to understand the dynamic efforts to which the components are submitted. In order to determine the loads suffered by the steering system of a vehicle in motion, the Group of Automotive Technology from the Lutheran University of Brazil (also known as “GTA”) conducted tests using a front-wheel drive road vehicle with a 1.4L transverse engine. The steering column (which joins the steering wheel to the steering gearbox ) and the tie rod (which connects the steering rack to the steering knuckle) were used as elastic elements to form load cells by the attachment of resistive strain gages in a full Wheatstone bridge.

Recent measurements and models show that the soot distribution and the permeability of the soot layer depend on the selected engine operating points both while loading and during regeneration. The influence of an upstream oxidation catalyst on the soot distribution has been shown. Most interestingly, a radial velocity profile has been observed by an optical measuring technique. However, in actual practice only the overall pressure drop due to the thousands of parallel channels of a wall flow filter is measured. In order to find out experimentally whether or not aging and thermal instability of diesel particle filter correlate with inhomogeneous flow conditions a simple set-up was developed to measure the outlet velocity profile. A Prandtl-tube with an inner diameter of 1 mm was scanned in x- and y-direction across the outlet channels of a catalytically coated wall flow filter, which was attached to a blower. The settings of its electro motor were kept constant in all the experiments.

This paper provides information on measurements and measurement techniques for particulate and unburnt hydrocarbon emissions from diesel engines. A dilution mini-tunnel was used to characterize the effects of the dilution ratio and sample temperature on the total particulate mass and soluble organic fraction(SOF) constituents. Increasing the sample temperature resulted in changes in the polynuclear aromatic hydrocarbon(PAH) constituents in SOF. The SOF was isolated by column chromatography, and the PAH fraction was determined by high performance liquid chromatography(HPLC). Column chromatography with silicagel, an octadecylsilan-bonded column, and keeping at high temperatures improved the analytical efficiency of HPLC. The gaseous hydrocarbon in raw exhaust was analysed by GC with FID. The temperature of the sample glass syringe affected measurements of high boiling point hydrocarbon constituents.

Measurement on turbulent premixed CH4/H2/air flames was studied experimentally. Hydrogen blending ratio is defined as the ratio of hydrogen to fuel, while CO2 dilution ratio is defined as the mole fraction of CO2 to those of mixture. Hydrogen blending ratios up to 0.2 and CO2 dilution ratios up to 0.1 were studied. OH profile of the instantaneous flame front was detected using the OH-PLIF visualizations on a turbulent Bunsen burner. 500 OH-PLIF images were used to obtain the turbulent burning velocity and calculate flame surface density, and 280 images was used to calculate the local curvature radius.

The use of damage tolerance analysis in the Aeronautical Industry have been required a most accuracy determination of the applied stress on component and assemblies. To obtain this, beyond the improvement in the stress calculation through finete element analysis, is very important the residual stress determination. This paper shows the adequacy of the hole drilling method to residual stress measuring in aluminum alloy 6061-T6 welded assemblies. In the component the residual stresses had reached values up to 130 MPa, being function of the fixture restraints during welding process. The heat treatment conditions of the stress relief were not effective into ranges that do not cause deletereous effect in the mechanical properties of 6061-T6 aluminum alloy.

This material presents a project for data acquisition applied to monitoring climatic road simulators. The developed system acquires accelerometers and thermocouple signals from the vehicle suspension and body, point-by-point. This implementation allows real-time monitoring during tests, with the objective of making is autonomous. The platform used for the data-logger and automation system is composed by analog and digital input/output, TCP/IP and OPC protocols. The result obtained by this approach consisted mainly on the possibility of mapping the vehicle response throughout the tests, the integration of climatic and vibration control and overall contribution to a higher use of road simulators.

This paper describes the ‘Measurement-Assisted Assembly’ activities led by the Final Assembly Line unit at Airbus - Toulouse. These activities are meant to eliminate some of the problems associated with the conventional process of locating and positioning large airframe sub-assemblies during the final assembly process, like fuselage-to-fuselage or wing to fuselage junctions. All these activities include laser or photogrammetry subsystems, computer-aided measuring systems, Best-Fit optimization software, specific Graphical User Interface. The combination of these technologies offers: jigless assembly, faster assembly process, rework and waste reduction and many more advantages.

To determine the power loss of hypoid gears often used as axle gears of vehicles a new test procedure has been developed. Hereby the power loss of the test rig can be directly measured using real application conditions. Measurements have shown that axle offset and lubricant have a big influence on the efficiency. Standardized efficiency tests especially for axle gears of passenger cars were worked out to determine the influence of lubricants. Hereby operating points representing common driving cycles are adjusted controled by a computer. These tests have shown that synthetic lubricants can increase the efficiency significantly at high torque.