A research undertaken to help blind people to navigate autonomously or with minimum assistance is termed as "Blind Navigation". In this research, an aid that could help blind people in their navigation is proposed. Distance serves as an important clue during our navigation. A stereovision navigation aid implemented with two digital video cameras that are spaced apart and fixed on a headgear to obtain the distance information is presented. In this paper, a neural network methodology is used to obtain the required parameters of the camera which is known as camera calibration. These parameters are not known but obtained by adjusting the weights in the network. The inputs to the network consist of the matching features in the stereo pair images. A back propagation network with 16-input neurons, 3 hidden neurons and 1 output neuron, which gives depth, is created. The distance information is incorporated into the final processed image as four gray levels such as white, light gray, dark gray and black. Preliminary results have shown that the percentage errors fall below 10%. It is envisaged that the distance provided by neural network shall enable blind individuals to go near and pick up an object of interest.
This paper presents incorporation of certain human vision properties in the image processing methodologies, applied in the vision substitutive system for human blind. The prototype of the system has digital video camera fixed in a headgear, stereo earphone and a laptop computer, interconnected. The processing of the captured image is designed as human vision. It involves lateral inhibition, which is developed using Feed Forward Neural Network (FFNN) and domination of the object properties with suppression of background by means of Fuzzy based Image Processing System (FLIPS). The processed image is mapped to stereo acoustic signals to the earphone. The sound is generated using non-linear frequency incremental sine wave. The sequence of the scanning to construct the acoustic signal is designed to produce stereo signals, which aids to locate the object in horizontal axis. Frequency variation implies the location of object in the vertical axis. The system is tested with blind volunteer and his suggestion in formatting, pleasantness and discrimination of sound pattern were also considered.
In polymer industries, the automation and control of reactors due to the progress in the areas of fuzzy control, neural networks, genetic algorithms, and expert systems lead to more secured and stable operation. When phenol and formaldehyde are mixed together, sudden heat is produced by the nonlinear exothermal reaction. Since sudden heat is liberated, polymerization process requires precise temperature control to avoid temperature run-away and the consequent damage to expensive materials. In practice, human involvement has been a source of errors that affects the quality of the product. This research proposes a design methodology for a sensor based computer control system. The duration of ON and OFF time of the relays is the parameters to be controlled in order to keep the exothermic reaction under control. This paper discusses a detailed simulation study of this exothermal process using MATLAB-SIMULINK-Fuzzy Logic toolbox. The model for the simulation study is derived from the constructed thermal system and responses are obtained. A predictive FLC structure is developed and compared to a classical PID control structure. Simulation results are obtained to ensure that the predictive FLC is better in controlling the reaction temperature.
Chemical Industries such as resin or soap manufacturing industries have reaction systems which work with at least two chemicals. Mixing of chemicals even at room temperature can create the process of exothermic reaction. This processes produces a sudden increase of heat energy within the mixture. The quantity of heat and the dynamics of heat generation are unknown, unpredictable and time varying. Proper control of heat has to be accomplished in order to achieve a high quality of product. Uncontrolled or poorly controlled heat causes another unusable product and the process may damage materials and systems and even human being may be harmed. Controlling of heat due to exothermic reaction cannot be achieved using conventional control methods such as PID control, identification and control etc. All of the conventional methods require at least approximate mathematical model of the exothermic process. Modeling an exothermal process is yet to be properly conceived. This paper discusses a design methodology for controlling such a process. A pilot plant of a reaction system has been constructed and utilized for designing and incorporating the proposed fuzzy logic based intelligent controller. Both the conventional and then an adaptive form of fuzzy logic control were used in testing the performance. The test results ensure the effectiveness of controllers in controlling exothermic heat.