Simulation of the PIR detector active function

The work deals with the behaviour of the PIR detector in an environment with great influence of a thermal background. It was necessary to perform simulations of the thermal behaviour of the sensor by COMSOL Multiphysics in different modes of heating the room to be able to prove that the PIR detector can function as an active detector with improved detection possibilities of intruders who would be invisible to a detector under normal circumstances. This confirms the detector’s ability to work on the principle of active detector, i.e. as transmitter and receiver of thermal radiation and evaluation of heat flux changes depending on the type of the heater and the shrouding

Design of active feedback for rehabilitation device

Sensor systems are an essential part of automated equipment. They are even more important in machines that come in contact with people, because they have a significant impact on safety. This paper describes the design of active feedback for rehabilitation device driven by pneumatic artificial muscles. Here are presented three methods for measuring the load of the robot. The first is a system composed of Force Sensitive Resistors (FSR) placed in the handle of the device. Two other methods are intended to measure the load of the actuator composed of artificial muscles. The principle of one method is to measure the difference in filling pressures of the muscles, second is based on strain measurement in the drive cables. The paper describes advantages and disadvantages of using each of these methods in a rehabilitation devic

Dividing of metal and plastic components of printed circuit boards

This paper contents one possibility of PCB separation due to the temperature due to the different thermal expansion of the metal path and the plastic from which the boards are made. Using the knowledge from the literary study and the simulation environments used, we have reached the maximum analysis of the problem. The separation of metal and plastic may occur due to temperature changes if the temperature difference is sufficient. We have carried out a study of printed circuit board production so we can choose the appropriate path of separation. Furthermore, we calculated the shear stress size required to tear the conductive copper paths from the epoxy resin. The temperature field in a two-layer board was modeled in the FEMLAB and Pro/ENGINEER programming environments. From the simulated temperature field simulations, conclusions can be drawn that accurately describe the condition and characteristics of materials subjected to heat shock. They derived the resulting relationship for calculating the resulting shear stress needed to separate the conductive paths and plastic materials of the PCB. In our own experiments, we used several ways to heat PCBs. The temperature is also sufficient for the separation of tin. After using the mechanical separation of the components, they were dropped from the PCB. Mechanical separation was also used when removing conductive paths. This separation is effective, but in the newer types of PCBs, the cyclical effects of thermal shock have to be applied to the separation of copper paths. Laboratory tests have demonstrated the viability of the proposed solution. The proposed method of recycling could lead to industrial use, which requires consistent sorting of waste electrical and electronic equipment

An analytical dynamic model of heat transfer from the heating body to the heated room

On the base of mathematical description of thermal balance the dynamic model of the hot-water heating body (radiator) was designed. The radiator is mathematically described as a heat transfer system between heating water and warmed-up air layer. Similarly, the dynamic model of heat transfer through the wall from the heated space to the outdoor environment was design. Both models were interconnected into dynamic model of heat transfer from the heating body to the heated room and they will be implemented into simulation model of the heating system in Matlab/Simulink environment

Simulation of printed circuit boards recycling process

This paper focused on the modeling of ecological PCB. Due to the high increase in the production of electronic waste, which contains a whole range of usable components, it is necessary to recycle it. About the study of the issue, we have proposed a solution for the separation of conductive paths from plastic and taking into account the legislative approaches and taking into account the existing methods of PCB separation, the composition, and production of PCBs and also the binders used in PCBs. We used the knowledge of process engineering to design a mathematical description of temperature fields in PCB and stress. To a great extent, we have devoted ourselves to the simulation experiments of PCB heating and cooling and the determination of temperature fields and stress due to temperature, cyclic mechanical stresses due to temperature. The simulation is performed in the Pro/ENGINEER and COMSOL Multiphysics® software environments, because of the possibility of solving multi-physical problems. Outputs from computer simulations are the initial stage for designing an eco-friendly way of recycling PCBs. In the future, we will focus on the more difficult issue of recycling multilayer PCBs. The development of new criteria for PCB recycling has opened new possibilities of treatment for used materials

The balance model for heat transport from hydrolytic reaction mixture

The content of the paper is the industrial application of enzyme hydrolysis of tanning solids waste with a view to minimizing the price of enzyme hydrolysate product, which has widely used. On the base of the energy balance of the enzymatic hydrolysis we estimated the critical minimal charge of a tanning drum. We performed of the critical minimal on the basis of a balance model for heat transport from reaction mixture into the environment through reactor wall. Employing a tanning drum for hydrolytic reaction allows to process tanning wastes in the place of their origin. It means thus considerably to enhancing economics of the whole process