An effective system for monitoring the wear of the machine tool inserts could significantly contribute to saving costs in manufacturing. One of the most recent and popular of effective monitoring methods revolves around the use of sensing technologies for indirect estimation of tool wear. The sensory information is difficult to collect from machine tools due to the extremely poor signal-to-noise ratio of the relevant tool wear-related information because the milling operation is of interrupted nature since the work piece is in contact with the tool edge several times per second. Another issue is the varying thickness of the chip during the penetration of the work piece. Yet, many challenges still impede the practical application of this method for industrial environment. Therefore, the paper presents a method that could solve these challenges especially in industrial environment. The proposed selfpowered wireless sensor node is integrated in the structure of the cutting tool. The voltage generated from the cutting tool vibrations of the harvester exponentially rises when the capacitor is fully charged and wireless signal sent to the receiver. As the intensity of energy accumulation depends on the state of the cutting tool wear, it indicates and detects the tool condition. The proposed technique could be useful for the identification of the cutting tool quality and the relative tool-work piece position. The information about the variation of tool wear is beneficial for helping the manufacturers to control the cutting process, to minimize the product cost as well as to improve the machining quality and efficiency.

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Automatic cab signaling system used in Lithuanian Railways is uninterruptible signaling system used to transmit the information about an allowable train speed to a cab driver. The performance of this system can be disturbed by various sources of disturbances. One of the main sources is a magnetization of rails. So far there were no other methods to evaluate disturbances that can cause signaling system errors than going by train and monitoring traffic-light signals in a cab. Therefore a system to record signaling system signals was created and a method to process the signals was proposed. The method can be used to make a signal processing and decoding of the previously decoded signals. Furthermore, the proposed algorithm uses slightly different method of signal processing and is potentially more immune to disturbances caused by the rail magnetization. The proposed algorithm was used to process the real signaling system signals. The signals were recorded on a route by going on an electric train. The main results of processing and potential places of disturbances have been shown. The advantage of the proposed algorithm over the currently used one need to be investigated in further research.

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