2.Select the SQUARE WAVE by pushing the WAVEbutton to choose the waveform of the output signal. 3.Press the 1 andkHzbutton to choose the frequency of the output signal. 4.Connect the probe that will be used as the input of the oscilloscope. 5.Push the Powerbutton to turn on the power supply of the oscilloscope. 6.Push the CH1button to display signal only from channel 1. (Make sure that any other buttons in this group must be pushed to OFF.) 7.Tune the POSITIONknob to the ground position of channel 1, where the horizontal bright line on the monitor is on the middle guideline. 8.Set the VOLTS/DIVknob to 500 mV/div. 9.Set the SEC/DIVknob to 0.5 ms/div. 10.Connect the probe to the output of the function generator by matching the red and black line. Question 1. Answer and record the following: The wave length of the signal: ______________________ division(s). The Vp-p of the signal: ____________________________ division (s). Convert the wave length to time: ____________________ seconds. Convert the wave length to frequency: ________________ Hz. Convert the Vp-p of the signal to volts: ______________ volts. 11.Change the output waveform to the SINUSOIDAL WAVEand the frequency to 2 kHzof the Function Generator and record the effect. 12.Change VOLTS/DIVto 1V/div and SEC/DIVto 1ms/div of the oscilloscope and record the effect. 13.Ask the TA for credit. (The TA will request each person in the group to show how to use Function Generator and Oscilloscope) (2 points) Typical question asked:Setup function generator to produce a 3 kHz sawtooth wave. Monitor the waveform by the oscilloscope to measure the corresponding Vp-p and frequency. Task 3. Generating PWM signal using function generator to drive the EV3 motorNow that you know the function of each wire in the EV3 connector, you should be able to use the function generator to generate the PWM signal required to run the EV3 motor. Follow the steps below to drive the EV3 motor. (Here, we define the high value of the PWM as 1and the low/ground value as 01.Switch on the function generator and set the voltage output to a square ware.(adjust the OFFSETto make peak-peak betweem 0v and 9v) )
ECE 456/556 Mechatronics Actuator – Lego EV3 Motor Lab Question Task TA Timed Exercise Page 5/11 2. Switch on the power supply and set the voltage output to Vcc = 4.5V and I = 1A. 3. Connect 1 siganl and Vcc to the two separate red pins in the breadboard and 0 signal to the ground pin in the breadboard. 4. Use the EV3 connector and wires to set up the breadboard to power up the EV3 motor. 5. When the motor is on, use the oscilloscope to probe the encoder output pin (pin #5 or #6) from the motor. Do not forget to connect the ground to the ground in the breadboard. Ask the TA to check your circuit set-up. 6. A PWM signal can be used to vary the motor speed. The average voltage and current of a PWM signal can be adjusted by modifying the duty cycle of the signal. Adjust the PWM siganl to drive the motor in diffferent speed. Fill in Table II according to different PWM settings. (Note: in order to change the duty cycle, you need to press SHIFT and DUTY and use the knob to change, the range would be 20% to 80%) Note: Encoder wheel and enclosure back parts. We have 12 slits in the encoder,
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- Resistor, TA, Pulse-width modulation, Lego EV3 motor