Jiri Kovar

Energy Harvesting from Mechanical Shocks Using a Sensitive Vibration Energy Harvester

This paper deals with a unique principle of energy harvesting technologies. An energy harvesting device generates electric energy from its surroundings using some kind of energy conversion method. Therefore, the considered energy harvesting device does not consume any fuel or substance. The presented energy harvesting system is used forenergy harvesting of electrical energy from mechanical shocks. The presented energy harvesting system uses a very sensitive vibration energy harvester, which was developed for an aeronautic application at Brno University of Technology. This energy harvesting system is a complex mechatronic device, which consists of a precise mechanical part, an electromagnetic converter, power electronics (power management) and a load (e.g., wireless sensor). The very sensitive vibration energy harvester is capable of usingthe mechanical energy of mechanical shocks and it can harvest useful energy. This energy harvesting system is used with a wireless temperature sensor and measured results are presented in this paper.

Design of Fuzzy Logic Controller for DC Motor

This contribution presents a simple and efficient approach to the fuzzy logic controller design and simulation. The proposed controller uses a Sugeno type fuzzy inference system (FIS) which is derived from discrete position state-space controller with an input integrator. The controller design method is based on anfis (adaptive neuro-fuzzy inference system) training routine. It utilizes a combination of the least-squares method and the backpropagation gradient descent method for training FIS membership function parameters to emulate a given training data set. The proposed fuzzy logic controller is used for the position control of a linear actuator which is a part of a Stewart platform.

Model-Based Design of Mobile Platform with Integrated Actuator – Design with Respect to Mechatronic Education

This paper deals with a model-based design of an actuator for a mobile platform. This paper presents way how to use model-based design of this mechatronic system with respect to mechatronic education. The presented mobile platform is used for shifting of a load in defined linear trajectory. Platform speed, maximal weight of the load and capacity of battery are used for the optimal actuator design. The actuator has to be integrated inside platform housing and it is limiting factor for design of this system. Several steps of model-based design are presented with respect of mechatronic approach and these steps are well known for our mechatronic students. The presented approach provides way how to develop such mechatronic system based on the model.

Introduction to design of speed controller for fuel pump

This contribution presents an efficient approach to design of speed controller for fuel pump. The fuel pump is used for two-shaft turbine engine concept with reducer driven by a free turbine. Controlling the amount of fuel injection into the combustion chamber is based on the speed control of the fuel pump which is controlled by the engine control unit according to the desired power mode. The resulting flow of fuel into the combustion chamber beside the pump speed regulator influences the bypass which constricts the return fuel according to pressure in the nozzles. Control characteristic of the bypass controller is fixed and is determined by its structure. The only adjustable parameter is the speed of the fuel pump. This paper describes the design procedure of this fuel pump using a two-level controller with speed and subordinate current-torque control.

Simulation modelling of water-supply network as mechatronic system

Mechatronics as an interdisciplinary field, which combines knowledge from multiple fields uses a comprehensive approach in the design of any technical object. It combines the requirements and their integration into all subsystems of the technical object. This approach, which is described by the VDI 2006 norm, can generally be used in the suggestion of regulation for the pressure pipe networks.

QUALITY OF ALUMINIUM ALLOY SURFACE AFTER WEDM

e-mail: mouralova@fme.vutbr.cz Efficient machining using wire electrical discharge machining (WEDM) technology is a compromise between cutting speed and resulting surface quality. Typical morphology of the surface machined by WEDM shows a plenty of craters caused by electrospark discharges produced during the cutting process. This work is focused on assessing the impact of machine setting parameters on quantitative and qualitative evaluation of the workpiece surface of aluminium alloy AlZn6Mg2Cu. Using metallography, the surface effects arisen during the process of wire spark erosion on cross-sections of preparations were studied. Using local spot EDX microanalysis, the chemical composition of the surfaces of the samples was studied. The attention was also paid to the highest height of profile of the craters, which were studied using 3D filtered images.

EXPERIMENTAL EVALUATION OF WEDM MACHINED SURFACE WAVINESS

Wire Electrical Discharge Machining (WEDM) an unconventional machining technology which has become indispensable in many industries. The typical morphology of a surface machined using the electrical discharge technology is characterized with a large number of craters caused by electro-spark discharges produced during the machining process. The study deals with an evaluation of the machine parameter setting on the profile parameters of surface waviness on samples made of two metal materials Al 99.5 and Ti-6Al-4V. Attention was also paid to an evaluation of the surface morphology using 3D colour filtered and non-filtered images.

Delta Robot Design

The article proposes an approach to the development of a Delta robot which is the most frequently used robot with a parallel kinematic structure for industrial fast pick and place applications. The approach is model based and it summarizes important steps for the successful design of a Delta robot for the given application including description of the kinematics, multi-body dynamics modelling and flexible bodies notes. This is demonstrated on the particular Delta robot developed at Brno University of Technology (BUT).

Effect of Width of Kerf on Machining Accuracy and Subsurface Layer After WEDM

Wire electrical discharge machining is an unconventional machining technology that applies physical principles to material removal. The material is removed by a series of recurring current discharges between the workpiece and the tool electrode, and a ‘kerf’ is created between the wire and the material being machined. The width of the kerf is directly dependent not only on the diameter of the wire used, but also on the machine parameter settings and, in particular, on the set of mechanical and physical properties of the material being machined. To ensure precise machining, it is important to have the width of the kerf as small as possible. The present study deals with the evaluation of the width of the kerf for four different metallic materials (some of which were subsequently heat treated using several methods) with different machine parameter settings. The kerf is investigated on metallographic cross sections using light and electron microscopy.

EVALUATION OF S-PARAMETERS ON THE SURFACE OF TITANIUM ALLOY TI-6AL-4V AND AL 99.5 MACHINED BY WEDM

e-mail: mouralova@fme.vutbr.cz Efficient machining using the technology of wire electrical discharge machining (WEDM) is a compromise between cutting speed and surface quality. Typical morphology of WEDM processed surface features plenty of craters caused by electrospark discharges produced during the cutting process. The study deals with the evaluation of S-parameters enabling quantitative evaluation of the surface in all directions which are technically significant. Attention was also paid to surface morphology and its evaluation using 3D colour-filtered and unfiltered images. The experiment included 33 variants of setting machine parameters on samples made of two metallic materials: Al 99.5 and Ti-6Al-4V.