The course, held substantially in presence in the laboratory-classroom, aims to provide students the basic skills to learn using modern instrumentation for data acquisition by programmable and reconfigurable virtual systems, according to user requirements for different applications. Methods to process and analyze statistically large data sets, and transmit and save them, will also be discussed.
The course includes, in addition to the traditional classroom lectures, tutorials and project workshops (not mandatory) where students will delve into specific topics, addressing different issues. The verification of the knowledge acquired is based on written tests during the course and on the evidence of recovery. The final evaluation will be based on a final exam where the students need to develop a custom application.
Introduction to measurement instrumentation. The analog-to-digital conversion; resolution and accuracy limits for numeric values; effective number of bits of the A/D converter and the dithering techniques to increase resolution. Description of the Data AcQuisition systems (DAQ) performances and limits; mode of installation and use of PCI cards for the acquisition channel and the generation of control signals. Introduction to the concepts of data interpolation and fitting.
Virtual instrumentation. The measuring instruments available on the market. The LabVIEW graphical environment. The front panel. The block diagram. Control palette and function palette, constants, indicators and controls. How to display data. Nodes and lines. Loop structures, case, sequence. Array and cluster. SubVI. Logic functions. Development of example programs. Debugging. Waveform Data. File management. Storing and recalling data into/from a file. Development of an algorithm for the measurement of the signal frequency.
Elements of hardware and software. Data acquisition cards. Specifications. Acquisitions with buffering. Local and global variables. Built-in elements. Practical examples and their implemetation.
Design and implementation of Virtual Instruments (VIs). Design and testing of a “digital voltmeter”. The acquisition section. The digital processing section. Indirect measures based on signal processing. Multichannel acquisition. Practical aspects of the multiplexer. Signal Conditioning. Implementation of “power meter” functions. Development of some practical applications. Processing of multi-channel data. Testing and calibration of a virtual instrument.
Applications. Output functions. Arbitrary signal generator. AD and DA converters total error evaluation. Use of the counters. Control gate. Acquisitions for long times. Use of virtual instruments through the Internet. Queues and semaphores to administrate data.
Instrumentation programming. Communication interfaces (RS232, GPIB). The driver for stand-alone instrumentation: SCPI, VISA. Communication with oscilloscopes and function generators via various communication interfaces.
Creation of virtual instruments for the acquisition from the field of experimental data: processing, graphical representation, data logging and statistical analysis (average, moving average, variance) of numerical data. Realization of programs for the measurement of analog and digital signals. Generation of analog and digital signals. Development of specific projects for students. Every student of Data Acquisition Systems held 32 hours of laboratory divided into 8 sessions during each session will be carried out individually but always under the guidance of the professor, the implementation of programs progressively more advanced. The details of the evaluation process of the workshop will be presented during the first hours of lesson of the course.
Basic knowledge of Computer Science are useful prerequisites to the course topics.