EXPERIMENT No.9 DATA COLLECTION AND CALLIBRATION OF SONAR PRE LAB TASK Objectives Enable students to collect data from sonar sensor in lab view. Enable students to calibrated sonar sensor in lab view. Introduction Mechatronics engineering is a cross-disciplinary field that combines mechanical and electronic design in control systems architecture though the application of computer programming. One of the most useful topics that can be covered in an introductory mechatronics course is the understanding and application of sensors. Various sensors are used in all types of industries. For example, in the automotive industry magnetic field transducers are used for throttle, pedal, suspension, and valve position sensing. In assembly line and machine automation, optical sensors are used for non-contact position sensing and safety. Piezo film sensors are installed in packages to log vibration history of a shipment. The QNET mechatronics sensors (MECHKIT) trainer is shown in Figure 1.1. It has ten types of sensors, two types of switches, a push button, and two LEDS. This QNET module can be used to teach the physical properties of most sensors used today, and the techniques and limitations of their application. There are 12 experiments: strain gage with flexible link, pressure sensor, piezo sensor, potentiometer, However.2. encoder. A timer calculates how long it takes for the signal to return and. sonar sensors are fitted with an emitter that generates ultrasonic waves and a receiver that captures them after hitting a target. switches and LEDs. For example. The sonar ranger on the mechatronic trainer is pictured in Figure 8. the distance of the remote target is measured. in general. Often used in mobile robotics. these devices do not have good close- range measurements and their resolution can be relatively coarse.1. temperature sensor. Theory The virtual instrument used to collect data using the sonar sensor is shown in Figure 8.infrared. given the speed of sound in air. sonar. Sonar sensors are great for long-distance measurements. magnetic field. The experiments can be performed independently.3. the one mounted on mechatronic board can go up to 21 feet. optical position. . and switch debounce analysis. The virtual instrument used to calibrate sonar range data is shown in Figure 8. . . 7. Experimental procedure Collect Data 1. Open and configure the QNET MECHKIT Sonar VI as described in Section 15. 5. Begin with the target close to the sonar sensor and slowly move it upwards. . as shown in Figure 8.2. Repeat for different target positions. 3. 9. 7. that is at least 10 by 10 cm2 with a reflective colour like white or yellow.Ensure J9 is set to Sonar. such as a sturdy piece of cardboard. Run QNET_MECHKIT_Sonar. The sonar sensor is linear. The slope and intercept are generated and the fitted curve is automatically plotted.2. Once its range of operation is found. Enter your collected target distances and voltages. Capture the Sensor Readings scope as well. Get a target. 6. Enter the corresponding measured voltage from the sonar sensor in the Sensor Measurement (V) array. enter the distance between the target and the sonar sensor in the Target Range (cm) array. Make sure the correct Device is chosen. LAB SESSION Apparatus/Equipment NI ELVIS II+ Board NI ELVIS II+ Adapter NI ELVIS II+ USB Cable Quanser Qnet Mechatronic Sensor Trainer Personal Computer Lab View Precautions Follow the safety rules of lab. as shown in Figure 8. 8. 2.vi 4. when the target is 10. e. 3. Run QNET_MECHKIT_Sonar. Make sure the coefficients are correct. Calibrate Sensor 1. Select the Calibrate Sensor tab and enter Gain and Offset coefficients to correctly measure the distance of the target.10. Click on Stop button to stop the VI. Results Questions: Instructor will ask Questions from the procedure followed and the results obtained orally for the lab assessment. 4.g. Enter Gain and Offset values used in Table 8. What is the resolution and operating range of the sonar sensor? How does the resolution and range compare with the IR sensor? 11.0 inches.0 inches away then the Sonar (inch) display should read 10. . Click on Stop button to stop the VI.2.vi 2. LAB REPORT Discussion of Results Conclusion /Summary References [1]Instructor Workbook QNET Mechatronic sensors trainer for NI ELVIs Developed by Quanser 2011 Curriculum designed by: Jacob Apkarian. SC.A. Quanser Paul Karam.A. M.. Quanser Michel Lévis. SC...SC.A. M.. Quanser . Ph. Quanser Peter Martin.D. B. 54 cm . What you have observered in readings <2.Questions: 1.24cm and >15. What is the operating range of the sonar sensor? 2. Does sound travel faster through water or through air? 6. What are its industrial/defense/transportation applications? 4. unto 15. How does the range compare with the IR sensor? 3.24 cm? . What are Active and Passive Sonar Sensors? 5. Save the VI as Continuous Simulate Temperature. 3. ❑ Locate the While Loop structure in the functions palette under Programming >> Structures. Create a 100 ms iteration time. ❑ Click and drag the loop over the entire code present on the block diagram. Create the While Loop.vi in the <Exercises>\LabVIEW Exercises directory. 4. 2. ❑ Open the functions palette and go to Programming >> Timing and select the Wait Function ❑ Place the Wait Function inside the while loop ❑ Right Click on the Wait function Left Terminal and select create Constant and chage the value of the constant to 100 . Exercise 2 Continuous Temperature Simulation VI Implementation 1. Open the Simulate Temperature VI and modify the block diagram by following the steps below. ❑ Select the while loop by left clicking on it. Run the VI ❑ Notice that the Run button shows an a broken arrow indicating an error ❑ Click on the error to see what is its cause. ❑ Correct the error by right clicking on the while loops conditional terminal and selecting Create >> Control. .5.