In order to detect and process underground vibration signal, this paper presents a system with the combination of software and hardware. The hardware part consists of sensor, memory chips, USB, etc. , which is respons...In order to detect and process underground vibration signal, this paper presents a system with the combination of software and hardware. The hardware part consists of sensor, memory chips, USB, etc. , which is responsible for capturing original signals from sensors. The software part is a virtual oscilloscope based on LabWindows/CVI （C vitual instrument）, which not only has the functions of traditional oscilloscope but also can analyze and process vibration signals in special ways. The experimental results show that the designed system is stable, reliable and easy to be operated, which can meet practical requirements.展开更多
A new passive adaptive shock absorber of the landing gear with double-cavity and dual-damping is studied. Its mathematical model and the virtual prototype are established based on the dynamics simulation software ADAM...A new passive adaptive shock absorber of the landing gear with double-cavity and dual-damping is studied. Its mathematical model and the virtual prototype are established based on the dynamics simulation software ADAMS. The landing dynamic characteristics and the effect of the parameters on the proposed adaptive shock absorber are analyzed. The results show that the proposed adaptive shock absorber has the slightly better landing performance at the normal load case and much less overload at the crudely landing case than the shock absorber with single-cavity and variable orifice. It also can be concluded that the overload of the proposed adaptive shock absorber can be reduced through increasing the volumes of both cavities or decreasing the pressure of the high pressure cavity or increasing the pressure of the low pressure cavity.展开更多
To improve I/O speed and system performance of network storage devices, a special storage server that is an iSCSI-based network-attached storage server (iSCSI-based network-attached storage server, for short iNAS) is ...To improve I/O speed and system performance of network storage devices, a special storage server that is an iSCSI-based network-attached storage server (iSCSI-based network-attached storage server, for short iNAS) is designed. The iNAS can provide both the file I/O and the block I/O services by an iSCSI module, and it converges with the NAS and the SAN (storage area network). The iNAS improves the I/O speed by the direct data access (zero copy) between the RAID (redundant array of inexpensive disks) controller and the user-level memory. The iNAS integrates the multi-RAID for a single storage pool by a multi-stage stripping device driver, and it implements the storage virtualization. In the experiments, the iNAS has ultra-high-throughput for both the file I/O requests and the block I/O requests.展开更多
A new dynamic path planning method in high dimensional workspace, radial based probabilistic roadmap motion (RBPRM) planning method, is presented. Different from general probabilistic roadmap motion planning methods, ...A new dynamic path planning method in high dimensional workspace, radial based probabilistic roadmap motion (RBPRM) planning method, is presented. Different from general probabilistic roadmap motion planning methods, it uses straight lines as long as possible to construct a path graph, so the final path obtained from the graph is relatively shorter and straighter. Experimental results show the efficiency of the algorithm in finding shorter paths in sparse environment.展开更多
A design strategy for a research platform of a telepresence telerobot system based on virtual reality technology is put forward. The design frame of the system is described, and its important core techniques are descr...A design strategy for a research platform of a telepresence telerobot system based on virtual reality technology is put forward. The design frame of the system is described, and its important core techniques are described. An octrees data structure is utilized to build kinematic and dynamic modeling of the virtual simulation environment, Delphi+OpenGL+3DS MAX are adopted to carry through the virtual modeling and visible simulation exploitation of the slave-robot and its environment. Photo-correction is adopted to correct positioning deviation of the virtual geometric model and modeling errors. The cost of software and hardware equipment for the research platform realized is low. The master/slave robot (manipulator) system and all software in the system were designed and manufactured by our research group. The performance of the system has reached the level required for research. An indispensable experiment base is provided for the research of a telepresence telerobot system based on virtual reality technology.展开更多
A calibration scheme under spherical coordinates is described for a magnetic tracker used in VR (virtual reality) system. A look up table containing data of tracked values for certain positions in the working space, ...A calibration scheme under spherical coordinates is described for a magnetic tracker used in VR (virtual reality) system. A look up table containing data of tracked values for certain positions in the working space, spe cified in spherical coordinates, is generated first, which is then used to calibrate the tracking results by a two dimensional interpolation. The scheme can effectively correct the static errors in the magnetic tracking system. The employment of spherical coordinates significantly reduces the calculation complexity in calibration.展开更多
A formulation of the multi degree of freedom equations of motion for damper connected adjacent multi story buildings under earthquake excitation is presented.The ground acceleration due to e...A formulation of the multi degree of freedom equations of motion for damper connected adjacent multi story buildings under earthquake excitation is presented.The ground acceleration due to earthquake is regarded as a stochastic process,and a pseudo excitation algorithm in frequency domain is implemented in a computer program to handle the non orthogonal damping properties of the system.The effectiveness of joint dampers is then investigated in terms of the reduction of displacement,acceleration and shear force responses of adjacent buildings.展开更多
In this paper,we have presented a simple approach for experimental and application study on LabVIEW based temperature transmitter with NI myRIO device in the laboratory.In this work,to study the small range of tempera...In this paper,we have presented a simple approach for experimental and application study on LabVIEW based temperature transmitter with NI myRIO device in the laboratory.In this work,to study the small range of temperature(40-100℃)although different temperature sensors can be used still,we have used here a K-type thermocouple as the measuring temperature sensor.The analog output voltage of thermocouple is amplified by instrumentation amplifier and the amplified signal is fed to the analog input of NI myRIO device which converts the analog input voltage signal as per the algorithm developed with virtual instrumentation based programming and provides the corresponding 4-20 mA output current signal in the analog output terminal of the device.Results show that input-output i.e.temperature-current relationship is linear.This low cost developed transmitter is very simple and it can be recommended for academic,scientific and industrial development of data acquisition systems,control and analysis of instruments.展开更多
Ventilation fans are one of the most important pieces of equipment in coal mines. Their performance plays an important role in the safety of staff and production. Given the actual requirements of coal mine production,...Ventilation fans are one of the most important pieces of equipment in coal mines. Their performance plays an important role in the safety of staff and production. Given the actual requirements of coal mine production,we instituted a research project on the measurement methods of key performance parameters such as wind pressure,amount of ventilation and power. At the end a virtual instrument for mine ventilation fans performance evaluation was developed using a USB interface. The practical performance and analytical results of our experiments show that it is feasible,reliable and effective to use the proposed instrumentation for mine ventilation performance evaluation.展开更多
Inductive coupling transmission system is an important measurement device for acquiring and transmitting marine environmental information.However,low transmission rate cannot meet the current demand for large data tra...Inductive coupling transmission system is an important measurement device for acquiring and transmitting marine environmental information.However,low transmission rate cannot meet the current demand for large data transmission in marine environment detection at home.In order to improve the transmission performance of the system in practical communication system,optimizing the design by directly changing the circuit parameters is time-consuming and expensive.Therefore,a set of inductive coupling transmission channel analysis system is designed based on virtual instrument to improve the transmission rate and reliability of inductive coupling transmission system.The bit error rate of channel system at different frequency and noise levels are tested by using three kinds of digital modulation mode including amplitude shift keying(ASK),frequency shift keying(FSK)and differential phase shift keying(DPSK),taking square wave and sine wave as a carrier.Finally,the sine wave is selected to be carrier signal and DPSK is chosen to be modulation mode.The reliable transmission of signal with the error rate less than0.005and the transmission rate of9600bps,at the noise level of-10dB,is realized and verified by the debugging circuit experiments with multi-nodes in the laboratory.The study provides an important experimental evidence for improving signal transmission reliability of inductive coupling transmission system.展开更多
Lock-in amplifiers are used to detect and measure very small alternating current(AC)signals down to the range of nVs.Accurate measurements can be made even when the small signals are buried by noise thousands of times...Lock-in amplifiers are used to detect and measure very small alternating current(AC)signals down to the range of nVs.Accurate measurements can be made even when the small signals are buried by noise thousands of times larger.With the digital signal processing(DSP)technology involved in modern instrumentation,a lock-in amplifier is more versatile in sensing and recovering small signals.Combining the virtual instrumentation technology,we reorganize the functional blocks of a programmable lock-in amplifier and build it as a virtual spectrum analyzer,virtual impedance meter,virtual network analyzer,virtual semiconductor parameter analyzer,signal generator,etc.A 4 layer model is used to implement these virtual instruments.The same virtual instrument can also be implemented on a general purpose FPGA developing board.展开更多
Operators suffer much diffieulty in manipulating miero-size objects without the assistance of friendly interfaces due to the scaling effects in micro worht. The paper presented a general framework for mieromanipulatio...Operators suffer much diffieulty in manipulating miero-size objects without the assistance of friendly interfaces due to the scaling effects in micro worht. The paper presented a general framework for mieromanipulation robot hased on virtual reality technology. With the framework we brought forward a FDH （Fixed Direction Hulls） based hounding box method to handle the eollision ,teteetion of the peg-in-hole mieroassembly. The eollision response model for the collision between micro needle and hole was presented. The virtual three and corresponding displacement were calculated with the model of bending deformation and pressing ,teformation. Experiments verify the validity of collision response model.展开更多
基金National Natural Science Foundation of China(No.61302159,61227003,61301259)Natural Science Foundation of Shanxi Province(No.2012021011-2)The Project Sponsored by Scientific Research for the Returned Overseas Chinese Scholars,Shanxi Province(No.2013-083)
文摘In order to detect and process underground vibration signal, this paper presents a system with the combination of software and hardware. The hardware part consists of sensor, memory chips, USB, etc. , which is responsible for capturing original signals from sensors. The software part is a virtual oscilloscope based on LabWindows/CVI （C vitual instrument）, which not only has the functions of traditional oscilloscope but also can analyze and process vibration signals in special ways. The experimental results show that the designed system is stable, reliable and easy to be operated, which can meet practical requirements.
基金Supported by the National Natural Science Foundation of China(60472118)~~
文摘A new passive adaptive shock absorber of the landing gear with double-cavity and dual-damping is studied. Its mathematical model and the virtual prototype are established based on the dynamics simulation software ADAMS. The landing dynamic characteristics and the effect of the parameters on the proposed adaptive shock absorber are analyzed. The results show that the proposed adaptive shock absorber has the slightly better landing performance at the normal load case and much less overload at the crudely landing case than the shock absorber with single-cavity and variable orifice. It also can be concluded that the overload of the proposed adaptive shock absorber can be reduced through increasing the volumes of both cavities or decreasing the pressure of the high pressure cavity or increasing the pressure of the low pressure cavity.
文摘To improve I/O speed and system performance of network storage devices, a special storage server that is an iSCSI-based network-attached storage server (iSCSI-based network-attached storage server, for short iNAS) is designed. The iNAS can provide both the file I/O and the block I/O services by an iSCSI module, and it converges with the NAS and the SAN (storage area network). The iNAS improves the I/O speed by the direct data access (zero copy) between the RAID (redundant array of inexpensive disks) controller and the user-level memory. The iNAS integrates the multi-RAID for a single storage pool by a multi-stage stripping device driver, and it implements the storage virtualization. In the experiments, the iNAS has ultra-high-throughput for both the file I/O requests and the block I/O requests.
文摘A new dynamic path planning method in high dimensional workspace, radial based probabilistic roadmap motion (RBPRM) planning method, is presented. Different from general probabilistic roadmap motion planning methods, it uses straight lines as long as possible to construct a path graph, so the final path obtained from the graph is relatively shorter and straighter. Experimental results show the efficiency of the algorithm in finding shorter paths in sparse environment.
文摘A design strategy for a research platform of a telepresence telerobot system based on virtual reality technology is put forward. The design frame of the system is described, and its important core techniques are described. An octrees data structure is utilized to build kinematic and dynamic modeling of the virtual simulation environment, Delphi+OpenGL+3DS MAX are adopted to carry through the virtual modeling and visible simulation exploitation of the slave-robot and its environment. Photo-correction is adopted to correct positioning deviation of the virtual geometric model and modeling errors. The cost of software and hardware equipment for the research platform realized is low. The master/slave robot (manipulator) system and all software in the system were designed and manufactured by our research group. The performance of the system has reached the level required for research. An indispensable experiment base is provided for the research of a telepresence telerobot system based on virtual reality technology.
文摘A calibration scheme under spherical coordinates is described for a magnetic tracker used in VR (virtual reality) system. A look up table containing data of tracked values for certain positions in the working space, spe cified in spherical coordinates, is generated first, which is then used to calibrate the tracking results by a two dimensional interpolation. The scheme can effectively correct the static errors in the magnetic tracking system. The employment of spherical coordinates significantly reduces the calculation complexity in calibration.
文摘A formulation of the multi degree of freedom equations of motion for damper connected adjacent multi story buildings under earthquake excitation is presented.The ground acceleration due to earthquake is regarded as a stochastic process,and a pseudo excitation algorithm in frequency domain is implemented in a computer program to handle the non orthogonal damping properties of the system.The effectiveness of joint dampers is then investigated in terms of the reduction of displacement,acceleration and shear force responses of adjacent buildings.
文摘In this paper,we have presented a simple approach for experimental and application study on LabVIEW based temperature transmitter with NI myRIO device in the laboratory.In this work,to study the small range of temperature(40-100℃)although different temperature sensors can be used still,we have used here a K-type thermocouple as the measuring temperature sensor.The analog output voltage of thermocouple is amplified by instrumentation amplifier and the amplified signal is fed to the analog input of NI myRIO device which converts the analog input voltage signal as per the algorithm developed with virtual instrumentation based programming and provides the corresponding 4-20 mA output current signal in the analog output terminal of the device.Results show that input-output i.e.temperature-current relationship is linear.This low cost developed transmitter is very simple and it can be recommended for academic,scientific and industrial development of data acquisition systems,control and analysis of instruments.
基金Project 2007E237 supported by the Science Fund Program of Shaanxi Province of China
文摘Ventilation fans are one of the most important pieces of equipment in coal mines. Their performance plays an important role in the safety of staff and production. Given the actual requirements of coal mine production,we instituted a research project on the measurement methods of key performance parameters such as wind pressure,amount of ventilation and power. At the end a virtual instrument for mine ventilation fans performance evaluation was developed using a USB interface. The practical performance and analytical results of our experiments show that it is feasible,reliable and effective to use the proposed instrumentation for mine ventilation performance evaluation.
基金National Natural Science Foundation of China(No.41506122)
文摘Inductive coupling transmission system is an important measurement device for acquiring and transmitting marine environmental information.However,low transmission rate cannot meet the current demand for large data transmission in marine environment detection at home.In order to improve the transmission performance of the system in practical communication system,optimizing the design by directly changing the circuit parameters is time-consuming and expensive.Therefore,a set of inductive coupling transmission channel analysis system is designed based on virtual instrument to improve the transmission rate and reliability of inductive coupling transmission system.The bit error rate of channel system at different frequency and noise levels are tested by using three kinds of digital modulation mode including amplitude shift keying(ASK),frequency shift keying(FSK)and differential phase shift keying(DPSK),taking square wave and sine wave as a carrier.Finally,the sine wave is selected to be carrier signal and DPSK is chosen to be modulation mode.The reliable transmission of signal with the error rate less than0.005and the transmission rate of9600bps,at the noise level of-10dB,is realized and verified by the debugging circuit experiments with multi-nodes in the laboratory.The study provides an important experimental evidence for improving signal transmission reliability of inductive coupling transmission system.
文摘Lock-in amplifiers are used to detect and measure very small alternating current(AC)signals down to the range of nVs.Accurate measurements can be made even when the small signals are buried by noise thousands of times larger.With the digital signal processing(DSP)technology involved in modern instrumentation,a lock-in amplifier is more versatile in sensing and recovering small signals.Combining the virtual instrumentation technology,we reorganize the functional blocks of a programmable lock-in amplifier and build it as a virtual spectrum analyzer,virtual impedance meter,virtual network analyzer,virtual semiconductor parameter analyzer,signal generator,etc.A 4 layer model is used to implement these virtual instruments.The same virtual instrument can also be implemented on a general purpose FPGA developing board.
文摘Operators suffer much diffieulty in manipulating miero-size objects without the assistance of friendly interfaces due to the scaling effects in micro worht. The paper presented a general framework for mieromanipulation robot hased on virtual reality technology. With the framework we brought forward a FDH （Fixed Direction Hulls） based hounding box method to handle the eollision ,teteetion of the peg-in-hole mieroassembly. The eollision response model for the collision between micro needle and hole was presented. The virtual three and corresponding displacement were calculated with the model of bending deformation and pressing ,teformation. Experiments verify the validity of collision response model.
