Types of Transducers and the Sensors that Make Up The Sensor Kit - Coursework Example

Assignment, Engineering and Construction Types of Transducers Introduction Transducers are instruments or devices that convert energy from one form to another. For example, a transducer can change energy from thermal to electrical, electrical to mechanical or mechanical to thermal. This study investigates various types of transducers as well as the sensors that make up the sensor kit. This is to assist in the study of interfaces between sensors and microprocessors, to develop real time closed systems. This study further involves comparison of diagrams of different transducers and the characteristic or behavior of their sensors. The transducers of interest to this project are inductive transducer, Hall Effect transducer, tacho generator, strain gauge transducer and reflective opto transducer. 2. Characteristics of Transducers 2.1. Inductive Transducer Inductive transducers work on the idea of variation between the self-inductance of an electromagnetic coil or of mutual inductance of an electric circuit. The variation of the inductance is set by altering porousness of the core in the coil. The second way of creating the variation is by increasing or reducing the number of windings of the coil that allows the current to flow. These are passive transducers requiring power supply and the output is analog in nature. Figure 1: Circuit Diagram for Inductive Transducer 2.2. Hall Effect Transducer A Hall Effect transducer or sensor has a way of varying the output voltages inside a magnetic field. The se transducers are used whenever it is necessary to change the distances and the position of the magnetic field, sensing current and speed of movement. It runs an analog sensor to produce a certain amount of voltages. The distance is detected by the use of the magnetic field, whose strength varies depending on the current. It is connected to a permanent magnetic core material, which covers the conductor being calibrated. Figure 2: Diagram for Hall Effect Generator 2.3. Tacho Generator This is an electromechanical device, which is able to produce electrical energy from mechanical sources of energy by turning a shaft. It produces voltages that are in proportion to the speed of turning the shaft when it is not joined to the load resistance. Figure 3: Circuit Diagram for Tachometer The voltage produced can also determine the rotational speed of the shaft. The common range for voltage signal is from zero to ten volts. 2.4. Strain Gauge Transducer This is a long set of electric conductor in a zigzag arrangement, that adds resistance upon stretching. This transducer is arranged in a similar direction to that of the strain. Figure 4: Circuit Diagram for Strain Gauge Transducer Figure 5: Circuit Characteristics when R2 and R4 stretched Figure 6: Circuit Characteristics when R1 and R3 Stretched Is there is a downward bend, it stretches the top gauges and compresses the bottom gauge. The transducer has a diaphragm that the pressure deforms. 2.5. Reflective Opto Transducer The reflective opto transducer consists of a Light Emitter Diode (infrared) and a phototransistor. In this transducer, the elements ordered in such a way that it reflect the beam back when a reflective surface is positioned at the right distance away from the LED. When the beam is directed to a non-reflective surface, it breaks the beam. Figure 7: Top view of Reflective opto Transducer Figure 8: Side view of reflective opto transducer The reflective surface is made of the Gray-coded disc. This disc is fixed very close to the transducers, about 4 millimeters away. The output emitter (phototransistor) becomes very low when the beam is not reflected. When there is a reflection of the beam, there is a high output. 3. Discussion The transducers displayed unique results with various input variables for each type of a transducer. 3.1. Results The general circuit diagram for the Reflective Opto Transducer. The transducers display certain characteristics in the transfer function following the data that was collected from the laboratory demonstration. The table below contains the data for displacement, amplitude of input voltage and output voltage. DISPLACEMENT (d) AMPLITUDE OF INPUT VOLTAGE (IV) AMPLITUDE OF OUTPUT VOLTAGE (OV) Input Gradient (IV / d) Output Gradient (OV / d) 0 100 14.6448 #DIV / 0! #DIV / 0! 0.001 100 0.459 100000 459 0.002 100 0.2331 50000 116.55 0.003 100 0.1562 33333.33 52.06667 0.004 100 0.1175 25000 29.375 0.005 100 0.0941 20000 18.82 0.006 100 0.0785 16666.67 13.08333 0.007 100 0.0674 14285.71 9.628571 0.008 100 0.059 12500 7.375 0.009 100 0.0525 11111.11 5.833333 0.01 100 0.0472 10000 4.72 0.011 100 0.0429 9090.909 3.9 0.012 100 0.0394 8333.333 3.283333 0.013 100 0.0364 7692.308 2.8 0.014 100 0.0338 7142.857 2.414286 0.015 100 0.0315 6666.667 2.1 0.016 100 0.0295 6250 1.84375 0.017 100 0.0278 5882.353 1.635294 0.018 100 0.0263 5555.556 1.461111 0.019 100 0.0249 5263.158 1.310526 0.02 100 0.0236 5000 1.18 17988.7 36.91901 Table 1: Input voltage and output voltage for the reflective opto transducer Figure 9: Amplitude of Voltage against Displacement Results for Inductive Transducer Displacement (d) Output Volt (V) Gradient (V / d) 0.00 0.097 #DIV/0! 0.005 0.08 16 0.010 0.06 6 0.015 0.042 2.8 0.020 0.03 1.5 0.025 0.025 1 Average Gradient 5.46 Table 2: Results for Inductive Transducers The following graph represents the results for inductive transducer. Figure 10: Output and input for Inductive Transducer Results for Strain Gauge Transducer: The process: The experiment was carried out by increasing the load on the beam and recording the voltage applied on the bridge. The next step was to prepare a table of the load, the bridge voltage and the theoretical stain. The table appeared as shown below: APPLIED LOAD (g) = L THEORETICAL STAIN (MS) = S BRIDGE VOLTAGE (mV) = V Theoretical Stain Gradient (S / L) Bridge Voltage Gradient (V / L) 0 0 0.1 #DIV/0! #DIV/0! 100 0.36 0.5 0.004 0.005 200 0.72 0.8 0.004 0.004 300 109 1.2 0.363 0.004 400 146 1.6 0.365 0.004 500 182 2 0.364 0.004 600 219 2.4 0.365 0.004 700 256 2.8 0.366 0.004 800 294 3.2 0.368 0.004 900 332 3.5 0.369 0.0039 1000 369 3.9 0.369 0.0039 0.294 0.00408 Table 3: Results for Strain Gauge Transducer Figure 11: The results or Strain Gauge Transducer The table below shows the data for bridge voltage against the theoretical stain. THEORETICAL STAIN (MS)= S BRIDGE VOLTAGE (mV) = bv Bridge Voltage Gradient (bv / S) 0 0.1 #DIV / 0! 0.36 0.5 1.3889 0.72 0.8 1.1111 109 1.2 0.0110 146 1.6 0.0110 182 2 0.0110 219 2.4 0.0110 256 2.8 0.0109 294 3.2 0.0109 332 3.5 0.0105 369 3.9 0.0106 Average 0.2587 Table 4: Theoretical Strain against Bridge Voltage Figure 12: Results for Bridge Voltage against Theoretical Stain 4. Results for Tacho Generator The table below contains the results for Tacho-Generator Speed of Rotation (S) Voltage Produced (V) Gradient for Voltage Produced (S / V) 100 0.645 0.0065 200 1.29 0.0065 300 1.935 0.0065 400 2.58 0.0065 500 3.22 0.0064 600 3.87 0.0065 700 4.515 0.0065 800 5.16 0.0065 900 5.8 0.0064 1000 6.45 0.0065 1100 7.09 0.0064 1200 7.74 0.0065 1300 8.385 0.0065 1400 9.03 0.0065 1500 9.675 0.0065 1600 10.32 0.0065 1700 10.965 0.0065 1800 11.61 0.0065 1900 12.255 0.0065 2000 12.9 0.0065 2100 13.545 0.0065 2200 14.19 0.0065 2300 14.835 0.0065 2400 15.48 0.0065 2500 16.125 0.0065 2600 16.77 0.0065 2700 17.415 0.0065 2800 18.06 0.0065 2900 18.705 0.0065 3000 19.35 0.0065 3100 19.995 0.0065 3200 20.64 0.0065 3300 21.285 0.0065 3400 21.93 0.0065 3500 22.575 0.0065 3600 23.22 0.0065 Average gradient 0.0065 Table 5: Voltage produced versus the speed of rotation For Tacho Transducer Figure 13: Results for voltage Produced against the speed of rotation Results for Hall Effect Transducer The following table contains the results for Hall Effect transducer: Current Through a Wire (I) Magnetic Field for the wire (MF) Magnetic Field Gradient (MF / I) Output Voltage From the Amplifier (OV) Output Voltage Gradient (OV / I) 0.1 0.00001 0.0001 0.04 0.4 0.2 0.00002 0.0001 0.08 0.4 0.3 0.00003 0.0001 0.12 0.4 0.4 0.00004 0.0001 0.16 0.4 0.5 0.00005 0.0001 0.19 0.38 0.6 0.00006 0.0001 0.23 0.383 0.7 0.00007 0.0001 0.27 0.38571 0.8 0.00008 0.0001 0.31 0.3875 0.9 0.00009 0.0001 0.35 0.388888889 1 0.0001 0.0001 0.39 0.39 1.1 0.00011 0.0001 0.43 0.390909091 1.2 0.00012 0.0001 0.47 0.391666667 1.3 0.00013 0.0001 0.51 0.392307692 1.4 0.00014 0.0001 0.54 0.385714286 1.5 0.00015 0.0001 0.58 0.386666667 1.6 0.00016 0.0001 0.62 0.3875 1.7 0.00017 0.0001 0.66 0.388235294 1.8 0.00018 0.0001 0.7 0.388888889 1.9 0.00019 0.0001 0.74 0.389473684 2 0.0002 0.0001 0.78 0.39 2.1 0.00021 0.0001 0.82 0.39047619 2.2 0.00022 0.0001 0.86 0.390909091 2.3 0.00023 0.0001 0.89 0.386956522 2.4 0.00024 0.0001 0.93 0.3875 2.5 0.00025 0.0001 0.97 0.388 2.6 0.00026 0.0001 1.01 0.388461538 2.7 0.00027 0.0001 1.05 0.388888889 2.8 0.00028 0.0001 1.09 0.389285714 2.9 0.00029 0.0001 1.13 0.389655172 3 0.0003 0.0001 1.17 0.39 3.1 0.00031 0.0001 1.21 0.390322581 3.2 0.00032 0.0001 1.24 0.3875 3.3 0.00033 0.0001 1.28 0.387878788 3.4 0.00034 0.0001 1.32 0.388235294 3.5 0.00035 0.0001 1.36 0.388571429 3.6 0.00036 0.0001 1.4 0.388888889 3.7 0.00037 0.0001 1.44 0.389189189 3.8 0.00038 0.0001 1.48 0.389473684 3.9 0.00039 0.0001 1.52 0.38974359 4 0.0004 0.0001 1.56 0.39 4.1 0.00041 0.0001 1.59 0.387804878 4.2 0.00042 0.0001 1.63 0.388095238 4.3 0.00043 0.0001 1.67 0.388372093 4.4 0.00044 0.0001 1.71 0.388636364 4.5 0.00045 0.0001 1.75 0.388888889 4.6 0.00046 0.0001 1.79 0.389130435 4.7 0.00047 0.0001 1.83 0.389361702 4.8 0.00048 0.0001 1.87 0.389583333 4.9 0.00049 0.0001 1.91 0.389795918 5 0.0005 0.0001 1.94 0.388 Average 0.0001 0.389488084 Table 6: Hall Effect Transducer Figure 14: Magnetic Field Versus Current Passing Through a wire Figure 15: Output Voltage Versus Current Passing through a wire. 3.2. Analysis The graphical representation of the characteristics of transducers reflects different gradients. Each of the tables measured the average gradient of the graphs with different input parameters. The experiment followed a similar process in which the measurements for the inputs were taken for each transducer and the output results were generated through computation of relevant models. 3.2.1. Inductive Transducer For the Inductive Transducer, the input parameter was the displacement of the coil material. The output parameters were the voltage produced and the gradient of the voltage against the displacement. From the analysis of the output, the average gradient of the graph was found to be a positive gradient of 5.46. This means that the greater the displacement, the higher the voltage that was generated. 3.2.2. Hall Effect Transducer For the Hall Effect Transducer, the input parameter was the current passing through the wire. The output results were the Magnetic Field for the wire (Tesla), the Magnetic Field Gradient, the Output Voltage from the Amplifier and the Output Voltage Gradient. The average gradient for the magnetic field against the current was found to be 0.0001. The analysis further found the average gradient for the output voltage to be a positive gradient of 0.3895. This meant that the greater the current that flowed through the wire, the stronger was the magnetic field that it created. The analysis finally discovered that the greater the greater the current, the stronger was the magnetic field produced. 3.2.3. Tacho Generator / Tachometer Tacho Generator (Tachometer) used the input variables as the Speed of Rotation of the shaft. The output results were the output voltage produced and the gradient of the voltage against the speed of rotation. The faster the shaft rotated, the greater the voltage that was measured. The analysis measured the average gradient of the graph as a positive value of 0.0064. In this regard, the voltage was found to be directly proportional to the speed of rotation. 3.2.4. Strain Gauge Transducer For the Stain Gauge Transducer, the only input variable was the load applied to the cantilever. The output results were the Theoretical stain (in MS), the bridge voltage (in mV), the Theoretical Stain Gradient and the Bridge Voltage Gradient. The theoretical Stain Gradient was found t be a positive value of 0.294 while the Bridge Voltage Gradient was a positive value of 0.00408. 3.2.5. Reflective opto transducer For the reflective opto transducer, the input variables were the displacement and the amplitude of the input voltage. The output variables were the amplitude of output voltage, the input gradient and the output voltage. The average gradient of the input voltage was found to be a positive value of 17988.69829. The average gradient of the output voltage variable was found to be a positive value of 36.92. The conclusion on this analysis was that greater the displacement and the amplitude of the input voltage the higher output voltage and the output variable. 3.2. Other Results of Reflective Opto Transducer The table below contains web Results for reflective opto transducer. Displacement (d) Input Volts IV Output Volts OV Input Gradient (IV / d) Output Gradient (OV / d) 0.05 50 0.59 1000 11.8 0.1 100 0.331 1000 3.31 0.15 150 0.2562 1000 1.708 0.2 200 0.2175 1000 1.0875 0.25 250 0.1941 1000 0.7764 0.3 300 0.1785 1000 0.595 0.35 350 0.1674 1000 0.47828571 0.4 400 0.159 1000 0.3975 0.45 450 0.1525 1000 0.33888889 0.5 500 0.1472 1000 0.2944 0.55 550 0.1429 1000 0.25981818 0.6 600 0.1394 1000 0.23233333 0.65 650 0.1364 1000 0.20984615 0.7 700 0.138 1000 0.19714286 0.75 750 0.1315 1000 0.17533333 0.8 800 0.1295 1000 0.161875 0.85 850 0.1278 1000 0.15035294 0.9 900 0.1263 1000 0.14033333 0.95 950 0.1249 1000 0.13147368 1 1000 0.1236 1000 0.1236   Average   1000 1.12840417 1. Conclusion Read More