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ECE 100 Fundamentals of LabVIEW Programming MATHEMATICAL FUNCTIONS in LABVIEW Activity No. 3 I. INTENDED LEARNING OUTCOMES At the end of this activity, the student shall be able to: 1. Enumerate the Mathematical Functions in LabVIEW and discuss its functions. 2. Use the Mathematical Functions of LabVIEW to analyze set of data according to set criteria. 3. Apply mathematical functions in LabVIEW to create a useful VI. II. BACKGROUND INFORMATION The previous activity has focused in the development of LabVIEW program using basic arithmetic, comparison and Boolean functions. This activity is a one-level higher continuation of Activity No. 2 which will be focusing on the use of elementary mathematical functions of LabVIEW. The elementary and special functions in LabVIEW include trigonometric, exponential, hyperbolic functions but not limited to discrete mathematics, Bessel functions, linear algebra, curve fitting, interpolation, extrapolation and optimization. LabVIEW can be used to interpret data that require the use and application of higher mathematical operations. A number of engineering design and analysis depends on how data will be treated. Say for instance, a set of data coming from a controlled experiment is tabulated and then plotted against the x and y axes. The programmer then noticed that the data points obtained are scattered everywhere in the plane. Mathematically, these data are remained untreated such that they cannot be evaluated directly by modelling the behaviour of experiment as a mathematical equation. To easily interpret these data, curve fitting may be employed. This means that the scattered data points may be represented closely by a geometric function including linear, polynomial and cubic function. Another application that a LabVIEW platform can administer is optimization. This technique is used to select the best possible elements in a group of data depending on a given criteria. For example, a metal can factory wants to design a can for preserved foods. Using the optimization techniques in LabVIEW the company can decide on how much dimensions of the can will give them the minimum cost of production with maximum capacity as much as possible. LabVIEW also offers tools for statistics. It includes measures of central tendency like mean, median and mode. Might as well, LabVIEW has the ability to interpret complex function, mathematical functions containing real and imaginary elements. To access the above functions, right-click anywhere in the block diagram windowMathematics. All functions that are not mentioned previously are located in that menu. To use the said functions, everyone should have a strong foundation in Engineering Mathematics including Algebra, Geometry, Calculus, Differential Equations, Advanced Engineering Mathematics, Probability and Statistics, Linear Algebra and Discrete Mathematics.

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ECE 100 Fundamentals of LabVIEW Programming III. LEARNING ACTIVITIES ACTIVITY 3.1: TRIGONOMETRIC FUNCTIONS 1. Open LabVIEW 2012 and let the Front Panel and Block Diagram windows appear. On the Block diagram window, right-click anywhere in the empty space and choose MathematicsElementaryTrigonometric and drag and drop the six basic trigonometric functions sin, cos, tan, csc, sec and cot. 2. On the Front Panel window, drag and drop a Knob control and connect the Knob control output node to the input nodes of the trigonometric functions. Change the scale of the Knob control from 0 (minimum) to 3.5 (maximum). Put Numeric Indicators for the output of the corresponding trigonometric function. Save your VI as Act3_1_1.VI

3. Click on the Run Continuously button and adjust the control knob as follows: a. 1.25 c. 1.57 b. 0.56 d. 3.13 Question: Explain how the VI works?

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ECE 100 Fundamentals of LabVIEW Programming 4. Consider the table below. Record the values of the six trigonometric functions for the given values below: Input values 0.00 0.50 1.00 1.50 2.00 2.50 3.00

SIN

COS

TAN

CSC

SEC

COT

5. Verify using your scientific calculator in DEGREE mode the values recorded on the table above. Question: Compare the results of the values tabulated above with the values you have computed using your scientific calculator. Is there any difference in the value? If there is a difference, why do you think so?

6. Modify the VI such that the value on your program and scientific calculator matches without omitting the values of control knob. Save the modified VI as Act3_1_2.VI. SCREEN-CAPTURE the Front Panel and Block Diagram for this procedure and include it in your activity report. ACTIVITY 3.2: EXPONENTIAL FUNCTIONS 1. Clear the Front Panel and the Block Diagram from the previous activity done. Create a Front Panel VI as shown below: Save VI as Act3_2_1.VI 2. On the Block Diagram Window, drag and drop Exponential functions. RightClick anywhere in an empty Space, go to Mathematics ElementaryExponential And drag and drop the ff: a. Exponential b. Exponential Arg (-1) c. Power of 10 d. Power of 2 e. Logarithm Base-10 f. Natural Logarithm Page 23

ECE 100 Fundamentals of LabVIEW Programming 3. Connect the Exponential function to Numeric Indicator labelled as Output 1. Connect Exponential Arg (-1) to Numeric Indicator labelled as Output 2. Connect the other functions in their respective indicators following the sequence from c to f in the previous page. 4. Consider the table below. Record the values for the given values below: Input values Exponential

Exp Arg (-1)

Power of 10

Power of 2

Log Base 10

Natural Logarithm

0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 6.00 6.50 7.00 7.50 8.00 8.50 9.00 9.50 10.00 Question: Explain each functions used in the calculation of the tables given above.

Question: What are the other functions under Exponential and explain each function?

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ECE 100 Fundamentals of LabVIEW Programming ACTIVITY 3.3: EXPONENTIAL FUNCTIONS 1. Clear the Front Panel and the Block Diagram from the previous activity done. Create a Front Panel VI as shown below:

2. On the Block Diagram, drag and drop the six hyperbolic functions and connect to its numeric indicator labeled Output 1 to Output 6 respectively. The hyperbolic functions in sequence should be sinh, cosh, tanh, sech, csch, coth respectively. Save your VI as Act3_3_1.VI 3. Consider the table below. Record the values for the given values below: Input values sinh cosh tanh csch 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 6.00 6.50 7.00

sech

tanh

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ECE 100 Fundamentals of LabVIEW Programming 7.50 8.00 8.50 9.00 9.50 10.00 Question: Explain each functions used in the calculation of the tables given above.

Question: What are the other functions under Hyperbolic Functions and explain each function?

IV. MACHINE PROBLEM 1. Given the following equations for a catenary Where s is half of the rope length, a is the parameter related to the mass of the rope and the acceleration due to gravity, and L is half the distance of the posts supporting the rope. The sag of the rope is given as:

Create a VI that will allow to compute the value of “d” for each of the given “s” and “L” from 0 to 1000. Use a dedicated control knob and customize your VI. Save your VI as MacPro3_1.VI 2. The Taylor Series expansion for the hyperbolic sine function is given as: ∑ While for the hyperbolic cosine is: ∑ Where n is the number of terms to be added to the series. Create a VI that would compute the sum of the first ten terms of the Taylor Series expansion for the hyperbolic sine and hyperbolic cosine of an input x, calling this VI as HypTaylor.VI Page 26

ECE 100 Fundamentals of LabVIEW Programming V. ASSESSMENT TASKS 1. What are the other Mathematics functions in LabVIEW apart from Trigonometric, Exponential and Inverse Hyperbolic functions? Enumerate their functions and define when they can be used?

2. What is the importance of having Mathematical functions in creating a program using LabVIEW?

3. When using a trigonometric function such that you want to compute for the six trigonometric functions of a given angle, how does LabVIEW interpret your input value?

4. Can we use the Mathematical functions of LabVIEW in the operation of an external device from the platform itself? How and why?

VI. CONCLUSION VII. RUBRICS FOR LABORATORY PERFORMANCE

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