MP4706 Sensors Instrumentation and Control

Compare the two terms in each question, supporting your answers with examples and drawings:

A.Mechatronics and measurement systems

B.Analogue and digital sensors

1.2Provide one method/ instrumentation that can be used to measure the following; support your answer with practical examples according to your study:

A.Position (non-contact sensor)

B.Speed (Electrical device)

C.Shaft Angle

D.Torque (Wireless)

E.Dynamic pressure

F.Liquid flow rate

1.3Explain the meaning of the following specifications for a typical pressure transducer; support your answer with drawings:

-Pressure Range: 70 – 1000 kPa; Temperature Range: -54ËšC to +120ËšC

-Full Range Output: 40 mV Supply Voltage: 10 V DC

-Non-linearity and Hysteresis Error: ±0.5% Full Range Output

-Thermal Zero Drift: 0.03 % Full Range Output /°C

1.4Define the calibration process, and discus how you can calibrate a throttle position sensor (TPS); support your answer with drawings and charts to show the dynamic response of the sensor when it is subjected to a unit step input; comment on the sensor response. What is the effect of temperature on the sensor output?

1.5A thermometer is initially at a temperature of 0ËšC and suddenly placed in a liquid at temperature of 80ËšC, which is maintained at this temperature. The thermometer has a 'time constant' of 1 second. What is the temperature value that the thermometer is expected to indicate after this time interval (1 second)? What is the time required to get the reading more than 99.3% from the step input?

2.1State/ draw the following for strain measurement using wire strain gauge (WSG):

A.WSG common resistance values.

B.Steps of the WSG installation.

C.Factors that could affect the WSG measurements.

D.Can USB-6003 NI DAQ used in Strain Gauge measurement?

2.2The Wheatstone bridge is used to measure the minute resistance changes in strain gauges when measuring strain. Explain briefly the advantages of using the Wheatstone bridge; use mathematical equations and sketches to illustrate your answer.

2.3For the Vehicle Scale shown, draw a suitable strain gauge arrangement (Full Bridge) to measure the weight of the vehicle and compensate for temperature and and bending strain, and find the maximum weight that can be measured using that scale. If WSG resistance is 350 Ω calculate the change in the gauge resistance at the maximum weight.

Given: the beam in the base is made from a square cross-section of 50x50 cm (as shown in Figure 3), the gauge factor S for each of the gauges is 2, the maximum output signal from the bridge Vo is limited to 100 mV and the supply voltage Vs is 10V.

You have been asked as an instrumentation engineer to develop a measurement system that can be used to evaluate Displacement and temperature sensors. For the task requested, provide the following:

3.1Develop a measurement software program using the NI LabVIEW software to provide the liquid level measurement, indicate (using LED) the liquid levels when it is less than 20% or over 80%, and log the measurement data; the LabVIEW software program file and logged data file should be sent by email to at the end of the assessment

- Available devices: NI Data Acquisition (DAQ) card, sensors kit- LED.

Explain how the type of the Analog-to-digital converter (ADC) can affect the DAQ output (support your answer with examples)? What is the type of the ADC that used in NI DAQ cards?

If your DAQ card has a maximum sampling rate of 300kS/s, what is the maximum analogue signal frequency that can be acquired? With the aid of drawing, discuss the aliasing problem that may occur during sampling of an analogue signal and mention how it can be avoided. (5 marks)

Given the PIC16F877A microcontroller and LCD (shown in Figure 2 below), provide a hardware design for a liquid level and temperature measurement system. Use the displacement sensor and thermocouple temperature sensor provided in your sensors kit. Include any other required electronic components.