Search

In this paper, we present a new mathematical model of three-axis force sensor for underwater robot fingers. We designed a kind of sensor based on this model which has a simple structure and can be miniaturized easily. By this model, they can be calculated that the magnitude, direction of finger force. Moreover, we present a new compensating method to decrease the error caused with the variation of temperature and pressure of water and caused with bending of the beams by symmetrical electronic circuits. We proposed compensation block method to solve the problem of heavy lead wire which affecting finger moving in underwater. Finally, an experiment is performed to verify the proposed model.

A faster algorithm for calculating the shortest distance between two spatial bodies based on existing algorithms was presented. A simulation analysis of missile models separation process was built by using this algorithm. The simulation proved that this algorithm has the same precision and faster speed compared with other existing algorithms.

Incinerator is an important prevent pollution equipment on ship, usually it is used to deal with some combustible rubbish, such as waste food waste, oil dishcloth, especially dirty oil and oil sludge. Through analyze the quantity of dirty oil and oil sludge that produced on ship, and calculate the exhaust gas heat energy that can be used from incinerator, the exhaust gas heat energy has plenty of energy from incinerator, it should be utilized and it will be a new way that to improve ship energy utilization efficiency.

Energy conservation and environmental protection is the two themes of the maritime transport development, through discussing the necessity of the incinerator waste heat utilization. Analysis the feasibility of incinerator waste heat using on ship air conditioning ,and puts forward specific technical plan to absorption refrigeration and air conditioning equipment using Marine incineration waste heat.

Main engine remote control system of modern ship with unattended engine room is vital for the navigational safety , through a starting trouble of the AUTOCHIEF-IV remote control system, analyzes the air starting process of the system from the “Local”“Bridge”“Engine Control Room”position ， identify the trouble reason and solve the fault, put forward the daily work of the special note, provide for work personnel to valuable reference.

According to some problems of Low efficiency of the current domestic Textile Machine，Reliability is bad，The operating personnel labor intensity，A single product varieties and so on. Design of electronic control system of high-grade textile machine based on CAN Bus. The system with RENESAS SH7047 chips as the controller chip, Realize the all of the interrupt signal, sensor signal detection, fuzzy PID algorithm and main shaft encoder location, Through the CAN bus transmission way to complete accuracy control ac servo system. The actual operation commissioning proves the electronic control system has the fast response, and robust, more kinds of textile and so on.

With the shortage of the petroleum resources day by day, the fuel oil price is becoming higher and higher. The ship companies want to use the heavy diesel oil and inferior fuel with lower price for the marine diesel. Temperature is a variable with great inertia. Using the PID control algorithm, which will lead to the consequence of over correction in the controlling process, the advantage of sliding mode variable structure control is the small over correction. In this paper, based on thermodynamics and heat transfer theory, the mathematical model of temperature control system is built, the sliding mode movement equation and the sliding mode variable structure controller is obtained. This makes the application of temperature control take the advantage of sliding mode variable structure control.

Based on researches on conventional analytical method of the Rayleigh wave testing data, the wavelet theory is introduced to analyze the data and we find that wavelet components of the Rayleigh wave testing data on the scale of 2-1 and 2-2 are high frequency interference, so we omit them. Afterwards, the coherent analysis, phase-different analysis and power spectrum analysis of the smoothing signal on the scale of 2-2 are made to obtain the frequency dispersion curve, which is smoother and more reasonable than that obtained without using wavelet denoising. Besides, the testing data of shear wave is closer to the calculated value. The results indicate that applying wavelet analysis to the disposal of the Rayleigh wave testing data works efficiently.

A tentative experiment has been conducted on polymer modified cement concrete now widely used. By filtering through 297 kinds of traces of polymer modified cement concrete samples tentatively mixed, we acquire a proper mix proportion, according to which, a total of 75 groups of 225 polymer modified cement concrete specimens are produced. After further selective preference of these specimens, ultrasonic test is done on the selected ones under different loading conditions. Afterwards, signal processing is accomplished by using wavelet transformation and we preliminarily find a kind of acousto-elastic sensitive concrete material which is comparatively sensitive to stress. This kind of material is produced by mixing epoxy resin, styrene-acrylic emulsion, acrylic emulsion, auxiliaries and iron powder into cement concrete together. The sensitivity of ultrasound and stress of this kind of modified concrete behaves preferably well as follows: at the low stress stage, not only the correlativity curve of ultrasound velocity and stress but also the correlativity curve of weighted spectrum area and stress arises apparently. If this kind of material can be applied to the practical engineering successfully, the acousto-elastic test accuracy of the concrete service stress will be greatly improved.

Electro-technical officer will be introduced and as a mandatory rating on board in the STCW78/10 amendments, the article introduces the origin and requirement of the ETO, analysis the impact on maritime authorities, ship management company and education and training institutions of navigation and puts forward some countermeasures, as well as soon as possible to provide the reference for our country to perform convention.