Search results for "Control unit"
showing 10 items of 10 documents
A stepper motor-driven microelectrode positioner
1987
The mechanical elements and the electronic control system from a stepper motor-driven microelectrode positioner is described. The unit embodies a high-precision small step angle hybrid motor. The compact, rugged and totally concentric design of the mechanic, by a spindle mechanism achieves the necessary precision by translating the stepwise rotations of the motor into steps of linear movement. The system takes advantage of commercially available low friction parts such as ball bearings, ball bushings and axles with hardened surfaces. The related electronic control unit is designed around the most recent integrated circuitry which is both sophisticated and economical. Though the described sy…
Piezosurgery in endoscopic dacryocystorhinostomy
2009
Piezosurgery is a recently developed system for cutting bone with microvibrations. The equipment consists of two hand pieces, two inserts, and two peristaltic pumps connected to the control unit. The device is endowed with an irrigation system of high-flow saline solution that breaks up into very small particles, with a “bloodless” effect on the surgical site and a low indirect thermal damage to the bone surfaces and adjacent structures. 4,5 The touch screen of the main unit permits selection of the specific insert, and modulation of the irrigation and the power according to the bone density. The device uses low-frequency ultrasonic waves (24.7-29.5 kHz), the applied power can be modulated …
A Study on the Use of Combustion Phase Indicators for MBT Spark Timing on a Bi-Fuel Engine
2007
The performance of a spark ignition engine strongly depends on the phase of the combustion process with respect to piston motion, and hence on the spark advance; this fundamental parameter is actually controlled in open-loop by means of maps drawn up on the test bench and stored in the Electronic Control Unit (ECU). Bi-fuel engines (e.g. running either on gasoline or on natural gas) require a double mapping process in order to obtain a spark timing map for each of the fuels. This map based open-loop control however does not assure to run the engine always with the best spark timing, which can be influenced by many factors, like ambient condition of pressure, temperature and humidity, fuel p…
PLZT laser beam modulator
1992
Abstract Laser beam modulator on transparent electrooptic PLZT ceramics are developed for the use in teaching process in schools and universities. Characteristics of the modulator and its electronic control unit are given.
Model-based optimization of injection strategies for SI engine gas injectors
2014
A mathematical model for the prediction of the mass injected by a gaseous fuel solenoid injector for spark ignition (SI) engines has been realized and validated through experimental data by the authors in a recent work [1]. The gas injector has been studied with particular reference to the complex needle motion during the opening and closing phases. Such motion may significantly affect the amount of injected fuel. When the injector nozzle is fully open, the mass flow depends only on the upstream fluid pressure and temperature. This phenomenon creates a linear relationship between the injected fuel mass and the injection time (i.e. the duration of the injection pulse), thus enabling efficien…
Spark ignition feedback control by means of combustion phase indicators on steady and transient operation
2014
In order to reduce fuel cost and CO2 emissions, modern spark ignition (SI) engines need to lower as much as possible fuel consumption. A crucial factor for efficiency improvement is represented by the combustion phase, which in an SI engine is controlled acting on the spark advance. This fundamental engine parameter is currently controlled in an open-loop by means of maps stored in the electronic control unit (ECU) memory: such kind of control, however, does not allow running the engine always at its best performance, since optimal combustion phase depends on many variables, like ambient conditions, fuel quality, engine aging, and wear, etc. A better choice would be represented by a closed-…
Embedded Model Control and dynamic simulation
2006
Embedded model control (EMC) is and end-to-end control technology addressed to industrial engineers and centered on the embedded model, a stylized discrete-time state equation of the whole plant, including environment, communication and computing resources. The embedded model, which is the core of the control unit, is derived and validated from a fine model of the plant which is implemented as a simulator code. The latter acts as a faithful and friendly test-bench where assessing control units before they are loaded into target processor. The paper illustrates the requirements and architecture of the EMC simulator under continuous improvement. A case study closes the paper.
On benchmarking the dependability of automotive engine control applications
2004
The pervasive use of ECUs (electronic control units) in automotive systems motivates the interest of the community in methodologies for quantifying their dependability in a reproducible and cost-effective way. Although the core of modern vehicle engines is managed by the control software embedded in engine ECUs, no practical approach has been proposed so far to characterise the impact of faults on the behaviour of this software. This paper proposes a dependability benchmark for engine control applications. The essential features of such type of applications are first captured in a general model, which is then exploited in order to specify a standard procedure to assess dependability measure…
Development and validation of a 5 stroke engine for range extenders application
2014
International audience; A 5-stroke turbo-charged port-injection spark-ignition engine has been developed in the present study for use as a range extender or series-hybrid main power source. The development and the design of the engine are based on 0D/1D model and experimental results have been compared with the engine model. The 5-stroke engine is a three-cylinder in which two cylinders perform a four-stroke cycle and alternatively a second expansion of the burnt gases is performed in the third cylinder. The boost pressure delivered by the turbocharger is controlled by a particular innovative system called “smart wastegate”, different from a conventional wastegate, consisting in a variable …
Design and Implementation of an Electronic Control Unit for a CFR Bi-Fuel Spark Ignition Engine
2017
In this work an Electronic Control Unit for the management of a CFR engine will be described. The engine, which is used both for fuel octane rating (both in terms of RON and MON) and for research purpose, is equipped with a double injection system, with the aim to independently operate both with liquid and gaseous fuels. The developed ECU, hence, is able to control the injections of both kind of fuel, together with the spark ignition. Furthermore the system is also able to measure fuel’s consumption, instantaneous engine speed of rotation and air-fuel ratio, showing all the running parameters both on a local LCD display and on a PC based graphical user interface.