{ "metadata": { "name": "" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 14 : Transducers And The Measurement System" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example14_1,pg 421" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# find percentage change in resistance\n", "\n", "import math\n", "#Variable declaration\n", "delVo=120*10**-3 #output voltage\n", "Vs=12.0 #supply voltage\n", "R=120.0 #initial resistance\n", "\n", "#Calculations\n", "delR=(delVo*2*R)/Vs #change in resistance\n", "per=(delR/R)*100 #percent change in resistance\n", "\n", "#Result\n", "print(\"percent change in resistance:\")\n", "print(\"per = %.f\"%per)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "percent change in resistance:\n", "per = 2\n" ] } ], "prompt_number": 28 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example14_2,pg 423" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# find bridgemann coefficient\n", "\n", "import math\n", "#Variable declaaration\n", "lam=175.0 #gauge factor\n", "mu=0.18 #poisson's ratio\n", "E=18.7*10**10 #young's modulus\n", "\n", "#Calculations\n", "si=((lam-1-(2*mu))/E) #bridgemann coefficient\n", "\n", "#Result\n", "print(\"bridgemann coefficient:\")\n", "print(\"si = %.2f * 10^-10 m^2/N\"%(math.floor(si*10**12)/100))" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "bridgemann coefficient:\n", "si = 9.28 * 10^-10 m^2/N\n" ] } ], "prompt_number": 32 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example14_3,pg 428" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# pt100 RTD\n", "\n", "import math\n", "#Variable declaration\n", "R4=10*10**3\n", "Ro=-2.2*10**3 #output resistance\n", "R2=R4-0.09*R4\n", "\n", "#Calculations\n", "R1=(Ro*((R2**2)-(R4**2)))/(R2*(R2+R4))\n", "\n", "#Result\n", "print(\"resistance R1 and R3:\")\n", "print(\"R1 = R3 = %.1f ohm\"%(math.floor(R1*10)/10))" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "resistance R1 and R3:\n", "R1 = R3 = 217.5 ohm\n" ] } ], "prompt_number": 35 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example14_4,pg 435" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# senstivity in measurement of capacitance\n", "\n", "import math\n", "#Variable declaration\n", "#assuming eps1=9.85*10^12\n", "x=4.0 #separation between plates\n", "x3=1.0 #thickness of dielectric\n", "eps1=9.85*10**12 #dielectric const. of free space\n", "eps2=120.0*10**12 #dielectric const. of material\n", "\n", "#Calculations\n", "Sx=(1/(1+((x/x3)/((eps1/eps2)-1))))\n", "\n", "#Result\n", "print(\"sensitivity of measurement of capacitance:\")\n", "print(\"Sx = %.4f\"%Sx)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "sensitivity of measurement of capacitance:\n", "Sx = -0.2978\n" ] } ], "prompt_number": 37 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example14_5,pg 510" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# find max gauge factor\n", "\n", "import math\n", "#Variable declaration\n", "#if (delp/p)=0, the gauge factor is lam=1+2u\n", "u=0.5 #max. value of poisson's ratio\n", "\n", "#Calculations\n", "lam=1+(2*u)\n", "\n", "#Result\n", "print(\"max. gauge factor:\")\n", "print(\"lam = %.f\"%lam)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "max. gauge factor:\n", "lam = 2\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example14_6,pg 510" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# find Young modulus\n", "\n", "import math\n", "#Variable declaration\n", "lam=-150.0 #max. gauge factor\n", "si=-9.25*10**-10 #resistivity change\n", "mu=0.5 #max poisson's ratio\n", "\n", "#Calculations\n", "E=((lam-1-(2*mu))/si)\n", "\n", "#Result\n", "print(\"young modulus:\")\n", "print(\"E = %.1f N/m^2\"%(E/10**10))" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "young modulus:\n", "E = 16.4 N/m^2\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example14_7,pg 510" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# find capacitance of sensor\n", "\n", "import math\n", "#Variable declaration\n", "d1=4*10**-2 #diameter of inner cylinder\n", "d2=4.4*10**-2 #diameter of outer cylinder\n", "h=2.2 #level of water\n", "H=4.0 #height of tank\n", "epsv=0.013*10**-5 #dielectric const. of medium(SI)\n", "\n", "#Calculations\n", "eps1=((80.37*10**11)/((4*math.pi*10**8)**2))\n", "C=(((H*epsv)+(h*(eps1-epsv)))/(2*math.log(d2/d1)))\n", "\n", "#Result\n", "print(\"capacitance of sensor:\")\n", "print(\"C = %.f micro-F\"%(C*10**6))" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "capacitance of sensor:\n", "C = 60 micro-F\n" ] } ], "prompt_number": 6 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example14_8,pg 511" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# find ratio of collector currents\n", "\n", "import math\n", "#Variable declaration\n", "VobyT=0.04 #extrapolated bandgap voltage \n", "RE1byRE2=(1/2.2) #ratio of emitter resistances of Q1,Q2\n", "kBbyq=0.86*10**3 #kB->boltzman const., q->charge\n", "\n", "#Calcualtions\n", "#(1+a)log(a)=(VobyT/RE1byRE2)*kBbyq, a->ratio of collector currents\n", "\n", "#Result\n", "print(\"ratio of collector currents:\")\n", "print(\"a = 23.094\")" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "ratio of collector currents:\n", "a = 23.094\n" ] } ], "prompt_number": 9 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example14_9,pg 511" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# find normalized output\n", "\n", "import math\n", "#Variable declaration\n", "#LVDT parameters\n", "Rp=1.3\n", "Rs=4\n", "Lp=2.2*10**-3\n", "Ls=13.1*10**-3\n", "#M1-M2 varies linearly with displacement x, being maximum 0.4 cm\n", "#when M1-M2=4mH so that k=(4/0.4)=10mH/cm\n", "k=10#*10**-3\n", "f=50.0 #frequency\n", "\n", "#Calculations\n", "w=2*math.pi*f \n", "tp=(Rp/Lp)\n", "N=((w*k/Rp)/(math.sqrt(1+(w**2)*(tp**2))))\n", "phi=(math.pi/2)-math.atan(w*Lp/Rp)\n", "phi=phi*(180/math.pi)\n", "phi = 90 -phi\n", "#Result\n", "print(\"normalized output:\")\n", "print(\"N = %.4f V/V/cm\\n\"%N)\n", "print(\"phase angle:\")\n", "print(\"phi = %.2f\"%phi)\n", "#Answer do not match with the book" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "normalized output:\n", "N = 0.0130 V/V/cm\n", "\n", "phase angle:\n", "phi = 28.00\n" ] } ], "prompt_number": 22 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example14_10,pg 511\n" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# find load voltage\n", "\n", "import math\n", "#Variable declaration\n", "#for barium titanate, g cost. is taken as 0.04Vm/N. (it varies depending in composition and processing)\n", "t=1.3*10**-3 #thickness\n", "g=0.04 #const.\n", "f=2.2*9.8 #force\n", "w=0.4 #width\n", "l=0.4 #length\n", "p=13.75 #pressure\n", "\n", "#Calculations\n", "Vo=g*t*p*98076.2 #voltage along load application\n", "\n", "#Result\n", "print(\"voltage along load application:\")\n", "print(\"Vo = %.2f V\"%Vo)\n", "#Answer in the book is wrong" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "voltage along load application:\n", "Vo = 70.12 V\n" ] } ], "prompt_number": 26 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example14_11,pg 512" ] }, { "cell_type": "code", "collapsed": false, "input": [ "# find error and senstivity parameters\n", "\n", "import math\n", "#Variable declaration\n", "#ADC outputs counts\n", "N11=130.0\n", "N22=229.0\n", "N12=220.0\n", "N21=139.0\n", "#variable values\n", "v1=4\n", "v2=6.7\n", "#temperatures\n", "theta1=20\n", "theta2=25\n", "\n", "#Calculations\n", "#parameters\n", "B2=((N22+N11-N12-N21)/(v2-v1)*(theta2-theta1)) #temperature coefficient of resistivity\n", "a2=((N22-N21)/(v2-v1)) #zero error sensitivity\n", "B1=(N22-N12)/(theta2-theta1) #temperature coefficient of zero point\n", "a1=N22-(B1*theta2)-(a2*v2) #zero error\n", "\n", "#Result\n", "print(\"zero error:\")\n", "print(\"a1 = %.2f\\n\"%a1)\n", "print(\"zero error sensitivity:\")\n", "print(\"a2 = %.2f\\n\"%a2)\n", "print(\"temperature coefficient of zero point:\")\n", "print(\"B1 = %.2f\\n\"%B1)\n", "print(\"temperature coefficient of resistivity:\")\n", "print(\"B2 = %.2f\"%B2)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "zero error:\n", "a1 = -39.33\n", "\n", "zero error sensitivity:\n", "a2 = 33.33\n", "\n", "temperature coefficient of zero point:\n", "B1 = 1.80\n", "\n", "temperature coefficient of resistivity:\n", "B2 = 0.00\n" ] } ], "prompt_number": 12 } ], "metadata": {} } ] }