Active tailstock for precise alignment of precision forged crankshafts during grinding

Within the Collaborative Research Centre 489 at the Leibniz Universitaet Hannover a new and innovative process chain for the manufacture of crankshafts is being investigated. By burr-free and near-net-shaped precision forging the process chain can be significantly shortened. However, this new production process requires a precise workpiece alignment before the grinding process due to the characteristics of the new process chain. In this paper a new machine-integrated positioning system consisting of an optical measurement system (sensor) and an active tailstock (actuator) is presented. For the detection of positioning errors, the geometric elements of the crankshaft are measured by the machine integrated optical measurement system. An algorithm evaluates the geometry data and calculates an adjustment vector. This vector contains the correction of the eccentric and tilt error. The degree of freedom (DOF) of the pendulum stroke of the grinding machine will be used to correct the eccentric error. The tilt error of the crankshaft is corrected by a new active tailstock. This tailstock produces a counter-tilt during the grinding process. For this purpose, a dynamic drive of the tailstock center in two DOF as a function of the angular position has been realized by two new developed piezo-hydraulic linear drives (stroke 4 mm). The dynamics and positioning accuracy of the active tailstock were verified. Up to 10 Hz a positioning accuracy in the range of ±1.5 μm can be achieved by using an iterative learning control. Furthermore, active alignment tests during grinding were performed

Optimization of 4-Cylinder Spark Ignition Engine for Fuel Consumption and Vehicle Performance through Cylinder Deactivation and Forced Induction

This project is conducted with the main objective of carrying out simulated engine modification concepts to find the best concept that addresses well on two criteria of the automobile industry, which are low fuel consumption and optimum vehicle performance for a city car. The focus of the project is set on gasoline engine, the more widely used engines for cars in Malaysia. For the purpose of analysis and comparison of the modified engine model, the PERODUA Myvi 1.3 SX is made as the benchmark, with the engine being a 1.3L K3-VE four-stroke four-cylinder gasoline engine

Analysis of block vibrations induced by combustion chamber pressure in a diesel engine

The paper describes an experimental methodology devised to study engine block displacement of internal combustion engine in the radial direction due to combustion force. This force produced in the cylinder varies with the chamber profile since flow parameters are influenced by the combustion chamber profile. Combustion effectiveness fluctuates depending upon flow parameters. To correlate between combustion and injection and to detect faults in the injection system it is necessary to supervise the combustion in the individual cylinders. This can be accomplished by evaluating the crankshaft speed at the flywheel. Speed is directly related to combustion by means of indicated pressure and torque. Different combustion chamber profiles were taken for the analysis along with speed and load as the design variables. The displacement and time-domain frequency for all the profiles were compared. The results provide displacement induced by the combustion pressure, uncertainty in combustion processes and nonlinear vibration of the engine block. This new approach in engine parameter design gives insight on the vibrational processes in the case of different chamber profiles as well as sources of noise in the diesel engine

Symbionte - Desarrollo de un dispositivo IOT enfocado en la protección y monitorización de compresores en aplicaciones de aire acondicionado y refrigeración

ilustraciones, fotografías a colorThis project addresses the problem of the correct diagnosis of air conditioning and refrigeration systems compressors, using instrumentation easily found in the market. For this work, the use of an Espressif ESP32 controller programmed under the Arduino language is proposed, in addition to sensors and algorithms based on trends that allow real-time knowledge of relevant variables of the process that allows anticipating to the failures under a scheme condition-based maintenance.Este proyecto aborda el problema del diagnóstico correcto de compresores de sistemas de aire acondicionado y refrigeración, utilizando instrumentación fácil de encontrar en el mercado. Para este trabajo se propone el uso de un controlador Espressif ESP32 programado bajo el lenguaje Arduino, además de sensores y algoritmos basados en tendencias que permitan conocer en tiempo real de variables relevantes del proceso que permitan anticiparse a los fallos bajo un esquema de mantenimiento basado en condiciones. (Texto tomado de la fuente)MaestríaMagíster en Ingeniería - Automatización IndustrialProcess and Machines Automation, Instrumentation, Tecnology for Educatio

Design and development of auxiliary components for a new two-stroke, stratified-charge, lean-burn gasoline engine

A unique stepped-piston engine was developed by a group of research engineers at Universiti Teknologi Malaysia (UTM), from 2003 to 2005. The development work undertaken by them engulfs design, prototyping and evaluation over a predetermined period of time which was iterative and challenging in nature. The main objective of the program is to demonstrate local R&D capabilities on small engine work that is able to produce mobile powerhouse of comparable output, having low-fuel consumption and acceptable emission than its crankcase counterpart of similar displacement. A two-stroke engine work was selected as it posses a number of technological challenges, increase in its thermal efficiency, which upon successful undertakings will be useful in assisting the group in future powertrain undertakings in UTM. In its carbureted version, the single-cylinder aircooled engine incorporates a three-port transfer system and a dedicated crankcase breather. These features will enable the prototype to have high induction efficiency and to behave very much a two-stroke engine but equipped with a four-stroke crankcase lubrication system. After a series of analytical work the engine was subjected to a series of laboratory trials. It was also tested on a small watercraft platform with promising indication of its flexibility of use as a prime mover in mobile platform. In an effort to further enhance its technology features, the researchers have also embarked on the development of an add-on auxiliary system. The system comprises of an engine control unit (ECU), a directinjector unit, a dedicated lubricant dispenser unit and an embedded common rail fuel unit. This support system was incorporated onto the engine to demonstrate the finer points of environmental-friendly and fuel economy features. The outcome of this complete package is described in the report, covering the methodology and the final characteristics of the mobile power plant

Development of a MR Hydraulic Bushing for Automotive Applications

The purpose of this work is to design a semi-active magnetorheological (MR) hydraulic bushing. The semi-active bushing is intended to be used to isolate a cylinder deactivating engine. Cylinder deactivation causes high transient torsional loading in addition to changing the magnitude and mode of engine vibrations requiring an adaptive or controllable isolator. Practical and simple semi-active control strategies are inspired by investigating the optimization of linear and slightly cubic nonlinear single degree of freedom isolators. Experimental verification of the optimization technique, which minimizes the root mean square (RMS) of engine acceleration frequency response and RMS of the force transmitted frequency response, shows that this method can be implemented on real linear systems to isolate the engine from harmonic inputs. This optimization technique is also applied to tune selected model parameters of existing two degree of freedom hydraulic bushings. This thesis also details the development of a MR hydraulic bushing. The MR bushing design retrofits an existing bushing with a pressure driven flow mode valve on the inertia track. A new efficient valve design is selected and developed for the application. The MR hydraulic bushing is designed, mathematically modeled, and numerically simulated. The simulation results show that the MR bushing tends to increase the low frequency dynamic stiffness magnitude while simultaneously decreasing the phase. The next stage of the project is fabrication and testing of the semi-active bushing. The performance of the manufactured MR bushing is tested on a base excitation apparatus. Varying the current input to the MR valve was found to have a small effect on the response of the suspended mass. The results are in agreement with the effects demonstrated by the dynamic stiffness numerical simulation