List the 5 components that are used for Analog to Digital conversion and describe what each one does

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List the 5 components that are used for Analog to Digital conversion and describe what each one does. [Document title] 2) (30 Points) The following part is placed under a load, F. The part has the following material properties: E=110GPa, YS=69MPa. Assume the part is brittle (i.e., will fracture near the yield strength). The attached strain gauge has a gage factor, F=20, and resistance of 100Ω with no strain. A 24-bit 5V ADC is used to sample the output. F V1 5V R2 10kΩ Rs Vo R1 100Ω F a) (3 point) What is the strain at failure? b) (3 point) What is the resistance at failure? c) (2 point) Find Vo when there is no strain on the part. [Document title] d) (2 point) Find Vo just before part failure. e) (2 point) Find Vo after part failure. f) (3 point) Design an op-amp circuit to output 0V when the strain is 0. Use a sample and hold circuit for the reference voltage. g) (3 point) Design another op-amp that takes the previous voltage output from (f) and outputs 5V after failure. [Document title] h) (4 point) What is the Quantization size, Q, of the ADC? i) (4 point) What is the resolution of the ADC over the operating range of the strain gauge before failure? (Hint: there is a voltage jump between part d. and part e. do not include this in the resolution because this is after part failure) j) (4 point) If the stress is applied at a rate of 10MPa/s, what is the maximum aperture time required by the ADC (assuming the ADC does not contain a sample and hold circuit)? (Hint: the voltage derivative may be approximated, or you may solve with MATLAB) [Document title] 3) (25 points) An evening at the beach turns into a life changing event after falling asleep on an inflatable raft. You wake up with no land in sight in any direction. Luckily, the next evening you awake to crashing waves on an uncharted island deep in the pacific. A brief investigation reveals that the island is inhabited by a society of intelligent dogs. Months pass and you learn to communicate with them in their complex language consisting of barks, winks, and nose licks. You find that of particular interest to the dogs is the topic of digital circuits and sensor systems. Over the years the dogs buried large quantities of food, wealth, and toys in various caches on the island. Unfortunately, many of these objects are bone shaped and of various sizes. Sorting these objects is obviously a challenge to creatures without hands, limited eyesight, and prone to distractions. In exchange for a handsome salary of 3 squirrels a day, they hire you to design a sorting system with the following categories: 1. Real bones 2. Toy bones 3. Gold bones (small) 4. Gold bones (large) 5. Squeaky toys (non-bone shape) List any assumptions you make to answer the following questions. Be sure to describe why each assumption is valid. You may assume the items are placed on a conveyer belt (or other delivery methods) to be sorted. You may also assume that any sensors, actuators, digital components you might need will by provided by the dogs. You may not assume that dogs will help with any of the sorting. a) (5 points) The dogs require a list of sensors necessary to perform the sorting. Develop a list of sensors and what they will be used for. b) (5 points) The dogs require a list of actuators. Provide a list below with a description of the function of each. [Document title] c) (5 points) Draw a picture of your sorting device labeling the actuators and sensors. d) (4 points) Provide a truth table relating the sensor input to actuator output. [Document title] e) (3 points) Write the Boolean expressions based on the truth table you developed above. f) (3 points) Draw the digital circuit diagrams for the expressions above to activate the actuators based on the input sensor data. [Document title] 4) (25 points) You are tasked with designing a control system for a voltage-controlled pin ball launcher. The launcher utilizes a rubber cylinder that ensures static friction when the ball comes in contact. The walls are frictionless. The ball absorbs energy while in contact with the rubber and is propelled with velocity, v. The design is shown below. ????1 = ????????????????????????????????12 ?????????????????????????22 8 8 , ????2 = , ???????????????????????????? = 0.0006????????, ????????????????????? = 0.003???????? ???????????????????? = 0.08????????, ????1 = 0.005????, ????2 = 0.01????, ???????? = 1 ?????????????? , ???????????? ???????? = 10 ?????????????? , ???????????? ???????? = 15 ????????? ???? Where kf is due to the internal friction loss of the motor, kL is due to the losses from the rubber cylinder, M is the mass of the marble, kt is the constant that relates the torque output to the input current. [Document title] The equivalent circuit for the motor is presented below. ???????? ? ????, ???? = 10????, ???? = 10????????, ???????????????? = ???????? ????, ???????? = 0.1 ????????? ???????????? a) (7 points) Derive a function that relates the voltage input to motor power output. (Hint: Ω(s) find the transfer function for ???? ????????(????) ????(????) and ???? ????????(????) then multiply them together to obtain the power) b) (7 points) Derive a transfer function that relate the voltage input to the output angle of the motor shaft. [Document title] c) (7 points) Assuming the marble is in contact with the rubber cylinder for π/3 radians. Estimate how long the marble is in contact with the rubber cylinder if the step input is V(s)=Vin/s. (Hint: check the coefficients in the denominator - some of them may be small enough to ignore when compared to the others) d) (4 points) Using the results from (a) and (c) estimate the velocity of the pin ball. You can assume all energy is converted into translational motion and Vin=5V. You can assume the motor has been operating at steady state when the ball is launched. ME330 Homework 8 Spring 2021 Directions: Answer the questions in the problem set below. Two to three questions will be randomly graded on correctness and the remaining questions will be graded on effort. In order to receive full credit on question graded on effort, a clearly honest attempt must be made. Merely restating the question or writing down non-relevant equations will result in a zero for the question. Students may collaborate on homework; however, it is highly recommended that student initially attempt homework alone prior to collaboration. 1) (3 points) Write a simplified Boolean expression and construct a truth table for the circuit below. Also complete the timing diagram for the output X (Section 6.3-6.5). 2) (1 point) Use basic Boolean algebra laws to prove the equation below (Section 6.5). (???? ? ????) + (???? ? ?????) = ???? ME330 Homework 8 Spring 2021 3) (3 points) Design a logic network given the prompt below (Section 6.6): You are tasked with designing a lock for a dog door. The door has four user settings: (1) The door opens for any animal that approaches via a motion sensor; (2) The door opens when dog approaches via a motion sensor and the dog has a proper collar RFID. This will allow only specific dogs in; (3) The door is always locked. This is useful for nighttime and vacations; (4) The door is always open unless a cat approaches via a camera system. To avoid false positives, the motion sensor must detect an animal approaching and the RFID sensor must be negative to close. This is an expensive addon for people who paranoid a cat might come in the house. a) b) c) d) Write a simplified statement for the prompt Write a Boolean expression. Draw the circuit diagram If I asked for a truth table, how many rows would it have? 4) (2 point) Write a Boolean expression for the truth table below (inputs A,B,C and output D). Simplify the expression and draw the circuit diagram. (Section 6.7). A 0 1 0 0 1 1 0 1 B 0 0 1 0 1 0 1 1 C 0 0 0 1 0 1 1 1 D 0 1 0 0 0 1 1 1 ME330 Homework 8 Spring 2021 5) (4 points) For the circuit below we would like to know the equation for Vout given Vin. Follow the steps below to obtain the solution: a) Find an equation for V1 in terms of Vin and Vout b) Find a transfer function, G2, for V2 in terms of V1 c) Find a transfer function, G3, for Vout in terms of V2 d) Draw a control system block diagram for the transfer functions above e) Now find the equation for Vout given Vin Vin R3 C2 R6 15kΩ 100mF 15kΩ U0 R1 15kΩ R2 15kΩ V1 U1 U2 V2 R5 L1 15kΩ 1mH R4 15kΩ 6) (2 points) Answer the following questions a. Explain why flip-flops are important to computing (Section 6.9). b. Discuss the differences between parallel and serial interface circuits. When is one used versus the other? (Section 6.10) Vout ME330 Homework 7 Due: 04/14/2020 Directions: Answer the questions in the problem set below. Two to three questions will be randomly graded on correctness and the remaining questions will be graded on effort. In order to receive full credit on question graded on effort, a clearly honest attempt must be made. Merely restating the question or writing down non-relevant equations will result in a zero for the question. Students may collaborate on homework; however, it is highly recommended that student initially attempt homework alone prior to collaboration. 1) ???? (????) 2) Find the transfer function ????(????) = ????????(????) for the amplifier circuit below ???? ???? (????) 3) Find the transfer function ????(????) = ????????(????) for the amplifier circuit below ???? ME330 Homework 7 Due: 04/14/2020 ???? (????) 4) Find the transfer function ????(????) = ????????(????) for the amplifier circuit below 5) Determine Vout given Vin in the circuit below. ???? Arduino Questions: These questions are intended to build your programming skills. They are graded on effort and are not subject to random grading on correctness. Note that plagiarism will result in a zero. Answer the questions in your own words. 6) Write an Arduino program which contains the following functions: a. Given 2 digital inputs output the digital OR b. Given 2 digital inputs output the digital AND c. Given 2 digital inputs output the digital NAND d. Given 2 digital inputs output the digital NOR e. Given 2 digital inputs output the digital XOR f. Call each function in the main loop and print the output with the serial monitor. ME330 Homework 8 Solutions 11/20/2020 1) 3 points ?????? ?????? (???? ???? = ?????????????????? ? ???? + ?????? ???? ? ???? ) + (???? ? ???? + ????) Apply De Morgan (????? + ????? + ????? + ????? ) + (???? ? ???? + ????) recall that ???? + ???? = ???? ???? = ????????????????????? (????? + ????? + ????? ) + (???? ? (???? + 1)) = ???? ? ???? ? ???? + (???? ? (1)) = ???? ? ???? ? ???? + ???? = ???? ? (???? ? ???? + 1) ???? = ???????????????? ???? =?????1=???? C 0 1 X 0 1 2) 1 point (???? ? ????) + (???? ? ?????) = ???? ? (???? + ?????) = ???? ? 1 = ???? 3) 3 points a) The door open if the motion sensor is true AND the code is set to 1 1 OR if the motion sensor is true AND the RFID is true AND the code is set to 0 1 OR if the code is set to 0 0 OR the camera reading is false for cats AND the code is set to 1 1 b) ME330 Homework 8 Solutions c) d) 25=32 4) 2 point (???? ? ????? ? ????? ) + (???? ? ????? ? ????) + (????? ? ???? ? ????) + (???? ? ???? ? ????) = ???? ???? ? ????? ? (????? + ????) + (???? ? ????) ? (????? + ????) = ???? A B ???? ? ????? + ???? ? ???? = ???? C D 11/20/2020 ME330 Homework 8 Solutions 11/20/2020 5) 4 points 6) 2 points a) They are used for memory. b) Parallel interface circuits store simultaneous inputs. Serial interface circuits store sequential inputs. ME 330 1) 2) 3) 4) Homework 7 Solutions Spring 2021 ME 330 Homework 7 Solutions 5) Note that frequency or time domain was not specified, so either is acceptable s Write the circuit in Laplace domain. The circuit is an inverting amplifier so: ???????????????? (????) ???? =− ???????????? (????) ???????? ???????????????? (????) = − ???? ???? (????) ???????? ???????? (Optional) transform back into the time domain: ???? ???? ???????????????? (????) = − ∫ ???????????? (????)???????? ???? 0 6) a) bool OR(pin1,pin2){ return pin1||pin2; } b) bool AND(pin1,pin2){ return pin1&&pin2; } c) bool NAND(pin1,pin2){ return !(pin1&&pin2); } d) bool NOR(pin1,pin2){ Spring 2021 ME 330 return !(pin1||pin2); } e) bool XOR(pin1,pin2){ return pin1^pin2; } f) void loop(){ bool pin1=digitalRead(1); bool pin1=digitalRead(2); Serial.println(OR(pin1,pin2)); Serial.println(AND(pin1,pin2)); Serial.println(NAND(pin1,pin2)); Serial.println(NOR(pin1,pin2)); Serial.println(XOR(pin1,pin2)); } Homework 7 Solutions Spring 2021 ME330 Homework 8 Spring 2021 Directions: Answer the questions in the problem set below. Two to three questions will be randomly graded on correctness and the remaining questions will be graded on effort. In order to receive full credit on question graded on effort, a clearly honest attempt must be made. Merely restating the question or writing down non-relevant equations will result in a zero for the question. Students may collaborate on homework; however, it is highly recommended that student initially attempt homework alone prior to collaboration. 1) (3 points) Write a simplified Boolean expression and construct a truth table for the circuit below. Also complete the timing diagram for the output X (Section 6.3-6.5). 2) (1 point) Use basic Boolean algebra laws to prove the equation below (Section 6.5). (???? ? ????) + (???? ? ?????) = ???? ME330 Homework 8 Spring 2021 3) (3 points) Design a logic network given the prompt below (Section 6.6): You are tasked with designing a lock for a dog door. The door has four user settings: (1) The door opens for any animal that approaches via a motion sensor; (2) The door opens when dog approaches via a motion sensor and the dog has a proper collar RFID. This will allow only specific dogs in; (3) The door is always locked. This is useful for nighttime and vacations; (4) The door is always open unless a cat approaches via a camera system. To avoid false positives, the motion sensor must detect an animal approaching and the RFID sensor must be negative to close. This is an expensive addon for people who paranoid a cat might come in the house. a) b) c) d) Write a simplified statement for the prompt Write a Boolean expression. Draw the circuit diagram If I asked for a truth table, how many rows would it have? 4) (2 point) Write a Boolean expression for the truth table below (inputs A,B,C and output D). Simplify the expression and draw the circuit diagram. (Section 6.7). A 0 1 0 0 1 1 0 1 B 0 0 1 0 1 0 1 1 C 0 0 0 1 0 1 1 1 D 0 1 0 0 0 1 1 1 ME330 Homework 8 Spring 2021 5) (4 points) For the circuit below we would like to know the equation for Vout given Vin. Follow the steps below to obtain the solution: a) Find an equation for V1 in terms of Vin and Vout b) Find a transfer function, G2, for V2 in terms of V1 c) Find a transfer function, G3, for Vout in terms of V2 d) Draw a control system block diagram for the transfer functions above e) Now find the equation for Vout given Vin Vin R3 C2 R6 15kΩ 100mF 15kΩ U0 R1 15kΩ R2 15kΩ V1 U1 U2 V2 R5 L1 15kΩ 1mH R4 15kΩ 6) (2 points) Answer the following questions a. Explain why flip-flops are important to computing (Section 6.9). b. Discuss the differences between parallel and serial interface circuits. When is one used versus the other? (Section 6.10) Vout ME330 Homework 7 Due: 04/14/2020 Directions: Answer the questions in the problem set below. Two to three questions will be randomly graded on correctness and the remaining questions will be graded on effort. In order to receive full credit on question graded on effort, a clearly honest attempt must be made. Merely restating the question or writing down non-relevant equations will result in a zero for the question. Students may collaborate on homework; however, it is highly recommended that student initially attempt homework alone prior to collaboration. 1) ???? (????) 2) Find the transfer function ????(????) = ????????(????) for the amplifier circuit below ???? ???? (????) 3) Find the transfer function ????(????) = ????????(????) for the amplifier circuit below ???? ME330 Homework 7 Due: 04/14/2020 ???? (????) 4) Find the transfer function ????(????) = ????????(????) for the amplifier circuit below 5) Determine Vout given Vin in the circuit below. ???? Arduino Questions: These questions are intended to build your programming skills. They are graded on effort and are not subject to random grading on correctness. Note that plagiarism will result in a zero. Answer the questions in your own words. 6) Write an Arduino program which contains the following functions: a. Given 2 digital inputs output the digital OR b. Given 2 digital inputs output the digital AND c. Given 2 digital inputs output the digital NAND d. Given 2 digital inputs output the digital NOR e. Given 2 digital inputs output the digital XOR f. Call each function in the main loop and print the output with the serial monitor. ME330 Homework 8 Solutions 11/20/2020 1) 3 points ?????? ?????? (???? ???? = ?????????????????? ? ???? + ?????? ???? ? ???? ) + (???? ? ???? + ????) Apply De Morgan (????? + ????? + ????? + ????? ) + (???? ? ???? + ????) recall that ???? + ???? = ???? ???? = ????????????????????? (????? + ????? + ????? ) + (???? ? (???? + 1)) = ???? ? ???? ? ???? + (???? ? (1)) = ???? ? ???? ? ???? + ???? = ???? ? (???? ? ???? + 1) ???? = ???????????????? ???? =?????1=???? C 0 1 X 0 1 2) 1 point (???? ? ????) + (???? ? ?????) = ???? ? (???? + ?????) = ???? ? 1 = ???? 3) 3 points a) The door open if the motion sensor is true AND the code is set to 1 1 OR if the motion sensor is true AND the RFID is true AND the code is set to 0 1 OR if the code is set to 0 0 OR the camera reading is false for cats AND the code is set to 1 1 b) ME330 Homework 8 Solutions c) d) 25=32 4) 2 point (???? ? ????? ? ????? ) + (???? ? ????? ? ????) + (????? ? ???? ? ????) + (???? ? ???? ? ????) = ???? ???? ? ????? ? (????? + ????) + (???? ? ????) ? (????? + ????) = ???? A B ???? ? ????? + ???? ? ???? = ???? C D 11/20/2020 ME330 Homework 8 Solutions 11/20/2020 5) 4 points 6) 2 points a) They are used for memory. b) Parallel interface circuits store simultaneous inputs. Serial interface circuits store sequential inputs. ME 330 1) 2) 3) 4) Homework 7 Solutions Spring 2021 ME 330 Homework 7 Solutions 5) Note that frequency or time domain was not specified, so either is acceptable s Write the circuit in Laplace domain. The circuit is an inverting amplifier so: ???????????????? (????) ???? =− ???????????? (????) ???????? ???????????????? (????) = − ???? ???? (????) ???????? ???????? (Optional) transform back into the time domain: ???? ???? ???????????????? (????) = − ∫ ???????????? (????)???????? ???? 0 6) a) bool OR(pin1,pin2){ return pin1||pin2; } b) bool AND(pin1,pin2){ return pin1&&pin2; } c) bool NAND(pin1,pin2){ return !(pin1&&pin2); } d) bool NOR(pin1,pin2){ Spring 2021 ME 330 return !(pin1||pin2); } e) bool XOR(pin1,pin2){ return pin1^pin2; } f) void loop(){ bool pin1=digitalRead(1); bool pin1=digitalRead(2); Serial.println(OR(pin1,pin2)); Serial.println(AND(pin1,pin2)); Serial.println(NAND(pin1,pin2)); Serial.println(NOR(pin1,pin2)); Serial.println(XOR(pin1,pin2)); } Homework 7 Solutions Spring 2021 ogtaain = 0 2a atfaiwn V Wot V,=0 f Rs10 V(lO) Sm V V. M- M V, M- Voet ts n wehave a tonke V,=V- Vo and is et Vaat, V (1070 1nv epouer sugh Smv 13m Vaxt,Vant-V, v- 48mV -93m Created with Scanner Pro Vnst,2r Vast,) R ( -0.098V Assupr )aotanin 1202 )stameland sizes 3 san lacatun onbelt 4 Cas ane alumim. sE Ep couctaniu Gtass weigt optic Plasttc ahamumam Cams Cam Ploctic Glass woat phto wtton Rota dleteton 1 ieur Created with Scanner Pro Vt Rea M2 Ly Va= Vmt + Re = Vut Rc d+ 4 -0 Va a5sune is v tang o N- VVrt F 1F Created with Scanner Pro b4 2 Fr 100 aF Eaxtal analA e) O A 2 0.2 del 0.v0 BL EKalrL 0, 0o1(2m) =0.002 m EEaxal=(Roo-a }p.nl) 2enM Phatca aihi A) B(stha)= V (E=o) =_20 2oa sthain-o oD fattwre 12V 1.9nV Created with Scanner Pro 1947 T S Solt un 2 Vo Vot Assue we have a anovb le power suppes tns ha powzsuf V(E=fal)»Vot(Raskona)Vost,e( failuna V(falurne)=00-12v =117mU Vat, 1 Vt 74.0 Vat 19.17- 49.17 AomV Vout G3.13 Vt, 74.20 Vgv Ta 2 -Z77 x)o Created with Scanner Pro Assumptum 3 efed PecCuhe iAgad Non-pnfet Whapped,Okay )Wanaped,Daaqed Reftuctve Paper Weget, Cordbond dousita sme Metalarn obTect, Heavy 3) Not-wiapped 4) Fmpy SWeapon OKay( No semsunneesn 2) Proxiwat(ultha kt smd) Lasvr sems0 (fhoto Pefef /Emuttn) tona Sanson 5ttaL efeetsensos Created with Scanner Pro ME330 Final Practice 1 12/08/2020 Answer the following questions as complete as possible. The initial equations for each question must be clearly specified if using software, and the final answers must be clearly stated. Include the input and output for the code. This exam must be completed individually. The exam is open book, open note, open internet. Please include any external references used. References must be from credible sources or points will docked. Any plagiarized material will result in a zero for the answer. 1) A 10ohm strain gauge of gauge factor, g, exhibits the resistance profile shown below: 10????, ???????????????????????? = 0 ????????(????????????????????????) = { 200????, ???????? ???????????????????????????? a) Design an op amp to take in Vo and output Vo,1=0 if strain=0. Rs Vo V1 5V R1 10kΩ b) Design a second op amp to take in Vo,1 and output Vo,2=5V at failure. c) What other signal conditioning should be done to Vo before amplification? Why? 2) You are tasked with designing a machine that sorts 12oz cans, plastic bottles, and glass bottles. Assume the containers are delivered on a conveyor belt and delivered one at a time. Select at least two sensors to perform the sorting. Determine the type(s) of actuators that will be used to performing the sorting. Explain how the actuators will be implemented. Draw a picture of the sorting device and explain how it works. Show the truth table relating the sensor input to actuator output. ME330 Final Practice 1 12/08/2020 3) Your favorite second cousin has been locked out of their primary domicile. You will leverage your mechatronic knowledge to help them out. Review the diagrams and descriptions below to answer the problem. ME330 Final Practice 1 12/08/2020 The cylinder lock above utilizes two pins of unequal length to validate a key. The equivalent resistance is dependent on the length and location of each pin: ???? ???? ???????? = ????1 + ????2 ???????? = ????1 ????−???? ???? ????−???? ???? + ???????? if lL ???????? = ????1 if l=L L Each pin is being pushed up by an independent voltage controlled linear actuator. a) b) c) d) Describe how the unlocked position can be detected (l=L) Design a circuit to detect when the l=L Design a circuit to store and hold the voltage for each pin Deactivate all pins simultaneously at user’s command 4) a) Design a 4-bit linear encoder using photo detector pairs. b) Design a grey code to binary output c) If the linear encoder is of length, L, what is the minimum change in length that can be detected? 5) A 100ohm strain gauge with a gauge factor of 2 measures a resistance change of 0.2ohms due to an axial stress parallel to the strain gauge on the object below. There are no other applied stresses. E=210GPa, R=10cm, L=2m ME330 Final Practice 1 a. Determine the strain on the object. b. Determine the axial displacement on the object. c. Determine the stress on the object. R L 12/08/2020 ME330 Final Exam Spring 2021 Answer the following questions as complete as possible. The initial equations for each question must be clearly specified if using software, and the final answers must be clearly stated. Include the input and output for any MATLAB code. This exam must be completed individually. The exam is open book, open note, open internet. Please include any external references used. References must be from credible sources or points will docked. Any plagiarized material will result in a zero for the answer. 1) The code below was written to cycle the brightness of an LED when a button is pressed, and the potentiometer is set to the correct values. Answer the following questions related to the Arduino code below. (15 points) a. Describe what the user must do for the print statement to occur. (5 points) b. Find at least two errors in the code that prevent it from functioning as intended. (10 points) ME330 Final Exam Spring 2021 ME330 Final Exam Spring 2021 2) You wish to read a signal from a sensor using a 12-bit ADC. The ADC maximum voltage is 5V and minimum voltage is 0V. (20 points) A 20ohm strain gauge of gauge factor, g, exhibits the resistance profile shown below: 20????, ???????????????????????? = 0 ????????(????????????????????????) = { 100????, ???????? ???????????????????????????? R1 12kΩ V1 12V Vo Rs a) Design an op-amp circuit to reduce the output voltage when the strain=0 to 0V. (7 points) b) Design a second op-amp to take the output from the first op-amp and output 5V at failure. (7 points) c) What is the maximum aperture this ADC should have, assuming it contains no sample and hold circuit, and an expected maximum input frequency of 1kHz? (6 points) ME330 Final Exam Spring 2021 3) Your engineering firm is hired by Santa Claus to sort presents and provide quality control. Upon arrival, you find that presents arrive from an interdimensional portal where you are told the elves reside. Unfortunately, the elves have also begun to manufacture weapons in the same factory for a Santa turned evil in a parallel universe. Due to the quantum nature and close proximities of the portals, some weapons are occasionally sent to (our) Santa’s workshop accidentally. The presents come in one at a time. You are required to sort them with the following criteria: (25 points) 1. Already wrapped presents 2. Presents already wrapped, but the package is damaged 3. Presents not yet wrapped 4. Empty packages 5. Potentially a weapon You can assume that all wrapped presents are in Rectangular cuboids. You can make other reasonable assumptions to aid your design (e.g. package alignment, package materials, toy materials, weapon material/size/weight, etc.). a) Select some sensors to perform the sorting. Describe how the sensors are used to sort the packages (8 points) b) Select some actuators to perform the sorting. Keep in mind that some items may be delicate depending on their category. Describe how each actuator is used (7 points). c) Draw a picture of the sorting device. Briefly explain how it works (5 points) d) Construct the truth table relating the sensor input to actuator output (5 points) ME330 Mechatronics Lecture 22 – Sensors N. A. Satterlee San Diego State University Department of Mechanical Engineering Spring 2021 SDSU ME330 1 Sensors • Readings • Ch. 9.3-9.7 SDSU ME330 2 Stress and Strain Measurement • Thin-Walled Pressure Vessel • ???????? = • ???????? = • ???????? = • ???????? = ???????? ???? ???????? 2???? ???? (???? 1−ν2 ???? ???? (???? 1−ν2 ???? ???? ???? 2???? ???? ???? ???? + ν???????? ) + ν???????? ) ???????? (???? + ν???????? ) ????(1−ν2 ) ???? 2???????? = (???? + ν???????? ) ????(1−ν2 ) ???? • ???? = ???????? = • ????= • We can determine the pressure with either gauge • Provided a thin-walled ideal vessel SDSU ME330 3 Stress and Strain Measurement • Strain Gage Rosette • How do we extract the strains from the strain gauge? • ???????? = ???????? ???????????? 2 ???????? + ???????? ????????????2 ???????? + 2???????????????????? ???????????????????? • ???????? = ???????? ???????????? 2 ???????? + ???????? ????????????2 ???????? + 2???????????????????? ???????????????????? • ???????? = ???????? ???????????? 2 ???????? + ???????? ????????????2 ???????? + 2???????????????????? ???????????????????? ???????????? 2 ???????? ???????? • ???????? = ???????????? 2 ???????? ???????? ???????????? 2 ???????? ????????????2 ???????? ????????????2 ???????? ????????????2 ???????? 2???????????????????? ???????????????????? 2???????????????????? ???????????????????? 2???????????????????? ???????????????????? SDSU ME330 ???????????? 2 ???????????? 2 ???????????? 2 ???????? ???????? ???????????? 2 4 Stress and Strain Measurement • ???????? ???????? ???????????? = 2 ???????? • ???????? = ???????????? −1 2 2 ???????????? ???????? ???????????? ???????? 2???????????????????? ???????????????????? ???????????? 2 ???????? ????????????2 ???????? 2???????????????????? ???????????????????? ???????????? 2 ???????? ????????????2 ???????? 2???????????????????? ???????????????????? −1 1 ν − 0 ???? ???? ???????? ν 1 ???????? − 0 ???? ???? ???????????? 2(ν+1) 0 0 ???? ???????? ???????? ???????? • Now we can use these stresses to find the principal stresses • Note: the book just lists solutions for typical strain gauges the above provides a more general solution SDSU ME330 5 Stress and Strain Measurement • Force Measurement with Load Cells • A flexural device containing multiple strain gauges on the surface • Depending on your application, these might be easier to implement and use SDSU ME330 6 Temperature Measurement • Temperature Conversions (Kelvin, Celsius, Fahrenheit, Rankine) • ???????? = ???????? − 273.15 • ???????? = 9 5 ???????? + 32 • ???????? = ???????? + 459.67 • Devices • • • • • Liquid-in-gas thermometer Bimetallic Strip Resistance Temperature Device Thermistor Thermocouple SDSU ME330 7 Temperature Measurement • Liquid-in-Glass Thermometer • The classic thermometer containing a working fluid which expands and contracts with temperature • The level of the fluid translates to a specific temperature determined by visual inspection • If we wanted to convert the level into a signal, how could this be accomplished? • Let’s think about the position sensors from the pervious lecture SDSU ME330 8 Temperature Measurement • Bimetallic Strip • Two metals joined together with different thermal expansions. When the strips are joined, there is no deflection, this is the reference temperature. As the temperature changes, the strip will deflect. It deflects in one direction for colder temperatures and the other direction for warmer temperatures. • The strip can also be coiled for a more compact design • If we wanted to convert the deflection into a signal, how could this be accomplished? SDSU ME330 9 Temperature measurement Electrical Resistance Thermometer • Resistance Temperature Device (RTD) • Leverages the material dependent coefficient of resistance. Typically platinum is used because of its stable resistancetemperature relationship, oxidation resistance, and high melting point. • ???? = ???????? [1 + ???? ???? − ???????? ] • Types • Thin Film elements • Wire wound elements • Coiled elements SDSU ME330 10 Temperature measurement • Thin Film elements • Metal deposited on a ceramic substrate via a deposition process. The film is then coated to protect the film. • Lower range of accuracy and limited temperature range due to internal strains incurred due to temperature changes. • Wire wound elements • Wire is wrapped around an insulating core. The coefficient of thermal expansion of the wire is matched by the core to minimize strain. • Coiled elements • A coiled wire is inserted into a bore of a ceramic tube. The coil is free to expand and contract with changing temperature so there is no associated mechanical strain. The housing is filled with a very fine ceramic powder to facilitate heat transfer. SDSU ME330 11 Temperature measurement • Thermistor • Semiconductor temperature sensor whose temperature changes exponentially with temperature. Generally, thermistor exhibit a negative temperature coefficient (NTC). So, the resistance decreases with increasing temperature. The relationship between resistance and temperature is given by • • • • • ???? 1 1 − ???? ????0 ???? = ???????? ???? ????: Characteristic Temperature – calibration constant of the material High accuracy Narrow operating range Fragile SDSU ME330 12 Temperature measurement • Thermocouple • Two dissimilar metal in contact form a thermoelectric junction that produces a voltage proportional to the temperature of the junction, known as the Seebeck effect. We can represent a thermoelectric circuit containing wires A and B forming two junctions at different temperature T1 and T2. The voltage can be computed by junction temperature difference. • ???? = ????(????1 − ????2 ) • Where ???? is the Seebeck coefficient – a temperature dependent material property SDSU ME330 13 Temperature measurement • Thermocouple • ???? = ????(????1 − ????2 ) • There is an issue here: We need a reference temperature to interpret the voltage. • The classic method is to implement an “ice bath” so the reference is always 0. But of course this is not practical. SDSU ME330 14 Temperature measurement • Thermocouple • To address the reference temperature issue, we can use a cheap temperature sensor that is accurate within the reference range. Generally this is a thermistor or silicon bandgap temperature sensor • The silicon bandgap sensor is just leveraging the temperature coefficient of a transistor. I.e. the forward current of a diode is temperature dependent. Therefore this temperature sensor is very cheap and can easily be integrated into a circuit. SDSU ME330 Temperature coefficient for a 2n2222 transistor 15 Temperature measurement • Thermocouple • The output of the thermocouple is also very low, it can be increased by placing thermocouples in serial. • We can increase the output voltage proportional to the number of thermocouples. This is called a Thermopile. SDSU ME330 16 Temperature measurement • The six more commonly used thermocouple metal pains are denoted by the letters E, J, K, R, S and T. The reference junction calibration for each of the types is nonlinear and can be approximated with a polynomial. SDSU ME330 17 Vibration and Acceleration Measurement • Accelerometer: A sensor design to measure acceleration due to motion, vibration and impact. • The inertial effects of a mass connected an object via a spring and dampener are measured by a displacement transducer. • Therefore when the object accelerates, the frequency response of the mass can be used to determine the acceleration. SDSU ME330 18 Vibration and Acceleration Measurement • This is like the problem in lecture 8, however there is no longer a force acting directly on the mass. • The relative displacement between the mass and object is • ???????? ???? = ???????? ???? − ???????? ???? • So the spring force can be expressed by • ???????? = ???????????? ???? • And the damper by • ???????? = ????????? ???? ???? • Newton’s second law • σ ???? = ????????? ???? ???? = −???????????? ???? − ????????? ???? ???? • ????(????? ???? ???? + ????? ???? ???? ) = −???????????? ???? − ????????? ???? ???? • −????????? ???? ???? = ???????????? ???? + ????????? ???? ???? + ????????? ???? ???? SDSU ME330 19 Vibration and Acceleration Measurement • Now let’s find the transfer function ???????? (????)/???????? (????) by taking the Laplace transform • −???????????? (????)???? 2 = ???????????? (????) + ???????????? ???? ???? + ???????????? (????)???? 2 • ???????? (????) ???????? (????) = −???????? 2 ???????? 2 +????????+???? = −???? 2 ???? ???? ???? 2 + ????+ ???? ???? • Recall that ???? = 2ζ???????? and ???????? = ???? for ???? ???? = • • ???? = 2ζ???????? and ???????? = ???? ???????? (????) −???? 2 = 2 ???????? (????) ???? +2ζ???????? ????+???????? 2 ???? ???? so ζ = ???? ???? 2 +????????+???? ???? 2 ???????? SDSU ME330 20 Vibration and Acceleration Measurement • To find the frequency response we simply substitute j???? for ???? and compute the magnitude • ????(????) = −????2 (????2 +2ζ???????? ????+???????? 2 ) • ???? j???? = • ???? j???? ????2 −????2 +2???????????? j????+???????? 2 = ????2 ???????? 2 = ????2 ???????? 2 ????2 ???? − 2+2???? ???? j+1 ???????? ???? 1 2 2 2 ????2 ???? 1− 2 +4???? 2 ???? ???????? ???? SDSU ME330 21 Vibration and Acceleration Measurement Suspended Mass • Example: MEMS capacitive accelerometer • Displacement is detected by changes in capacitance Contact Spring • Movement up increases capacitance in top contact • Movement down increases capacitance in bottom contact Capacitor SDSU ME330 22 Vibration and Acceleration Measurement • Piezoelectric Accelerometer • Application of an electric field to a piezoelectric causes a deformation, but the reciprocal is also true. Deformation of a piezoelectric results in charge polarization across the crystal. • Acceleration causes relative displacement between the case and the mass. • The resulting strain in the crystal causes a charge displacement that can be measured as a voltage • Requires no external power supply SDSU ME330 23 Pressure and Flow Measurement • Capacitive Pressure Sensor • Increased pressure changes results in diaphragm deflection which is measured by capacitance • Pirani Gauge • Conductive heat transfer is proportional to the density of a fluid. Therefore the rate of heat change from a heated wire will be proportional to the ambient pressure. A MEMs implementation of a capacitive pressure sensor and Pirani gauge in one package SDSU ME330 24 Pressure and Flow Measurement • Flow meters • Mechanical Flowmeters: Based on positive displacement over a period of time to determine flow rates • Pressure based Flowmeters: Rely on Bernoulli’s principle to determine flow rates • Thermal Mass Flowmeters: A heated wire is suspended in the fluid. The temperature and resistance of the wire are dependent on the amount of heat transferred. A downstream temperature sensor is used in conjunction to determine the flow • Doppler: Laser or ultrasonic – doppler effect is used to determine the fluid speed via frequency shift SDSU ME330 25 ME330 Mechatronics Lecture 24 – Actuators N. A. Satterlee San Diego State University Department of Mechanical Engineering Spring 2021 SDSU ME330 1 Actuators • Readings • Ch. 10.1-10.8 SDSU ME330 2 Course Updates 1. Project Grades • The project is intended to provide students with practical experience • The project grade will be favorably curved to ensure it does not impact student grades 2. Final Grades • If beneficial to students, the final grades will be curved, this is currently not the case SDSU ME330 3 Course Updates • Resume Updates • • • • • • • • • • Simulink Multisim Breadboarding Analog/Digital Circuit Design and Analysis Microcontrollers Arduino Some C/C++ Control Systems Mechatronics Group Project (with sentence description) • Missing anything? SDSU ME330 4 DC Motor Equations • Back emf • Motor is also a generator • Current induced opposes applied force • A simplified model is presented to the right, but the same idea applies to a permanent magnet (PM) motor • The current generated is proportional to the velocity SDSU ME330 Velocity F B B S N S N 5 DC Motor Equations 1. ???? = ???? ???????? + ???? × ???? Where: • ????: Force on electron in wire • ????: Induced electric field (battery) • ????: velocity of the electron • ????: Magnetic field • ????: Charge F Vw V B B EB S N S N 2. ???????? = ???????? × ???? • ???????? : Induced electric field (moving wire) • ???????? : velocity of wire • ????: Magnetic field SDSU ME330 Ew 6 DC Motor Equations 1. The electric field generates a force on the electrons and cause them to flow through the wire with velocity, V 2. The electrons moving through the magnetic field generate a force, F, on the wire 3. The force on the wire causes the wire to move with velocity, Vw 4. The movement of the wire through the magnetic field generates an electric field in the wire F Vw V B B EB • This electric field is in the opposite direction of the original electric field • The higher the velocity, the greater the electric field SDSU ME330 S N S N Ew 7 DC Motor Equations • From this we determine there is feedback from the velocity 1. The force linearly is proportional to the current (From Equation 1) • ???? = ???????????????? • ???? = ???????????????????? = ???????? ???????????? 2. The back EMF is linearly proportional to the velocity (From Equation 2) • ???????????????? = ???????? ???? 3. Now we just solve these two systems like normal electrical and mechanical systems Motor Equivalent Circuit Armature Equivalent Diagram SDSU ME330 8 DC Motor Equations • ???????????? = ???????????????? ???? ???????? + ???????????????? + ???????? ???? • ???????????? : current through motor • ????: winding resistance • ???????? : electrical constant of the motor (back EMF) • ???????? : the resistive loss in the magnetic circuit • Loss due to dissipation in electromagnetic energy (e.g. heat) • Generally, RL