3d printed rotary table quotation

Along 3 years I have been trying several leg mechanism, at first I decided to do a simple desing with tibial motor where placed on femur joint.This design had several problems, like it wasn"t very robust and the most importat is that having the motor (with big mass) that far from the rotating axis, caused that in some movements it generate unwanted dynamics to the robot body, making controlability worse.New version have both motors of femur/tibial limb at coxa frame, this ends with a very simple setup and at the same time, the heaviest masses of the mechanism are centered to the rotating axis of coxa limb, so even though the leg do fast movements, inertias won"t be strong enough to affect the hole robot mass, achieving more agility.Inverse Kinematics of the mechanismAfter building it I notice that this mechanism was very special for another reason, at the domain the leg normally moves, it acts as a diferential mecanism, this means that torque is almost all the time shared between both motor of the longer limbs. That was an improvent since with the old mechanism tibial motor had to hold most of the weight and it was more forced than the one for femur.To visualize this, for the same movement, we can see how tibial motor must travel more arc of angel that the one on the new version.In order to solve this mechanism, just some trigonometry is needed. Combining both cosine and sine laws, we can obtain desired angle (the one between femur and tibia) with respect to the angle the motor must achieve.Observing these equations, with can notice that this angle (the one between femur and tibia) depends on both servos angles, which means both motors are contributing to the movement of the tibia.Calibration of servosAnother useful thing to do if we want to control servo precisely is to print a calibration tool for our set up. As shown in the image below, in order to know where real angles are located, angle protactor is placer just in the origin of the rotating joint, and choosing 2 know angles we can match PWM signal to the real angles we want to manipulate simply doing a lineal relation between angles and PWM pulse length.Then a simple program in the serial console can be wrtten to let the user move the motor to the desired angle. This way the calibration process is only about placing motor at certain position and everything is done and we won"t need to manually introduce random values that can be a very tedious task.With this I have achieved very good calibrations on motors, which cause the robot to be very simetrial making the hole system more predictable. Also the calibration procedure now is very easy to do, as all calculations are done automatically. Check Section 1 for the example code for calibration.More about this can be seen in the video below, where all the building process is shown as well as the new leg in action.SECTION 1:In the example code below, you can see how calibration protocol works, it is just a function called calibrationSecuence() which do all the work until calibration is finished. So you only need to call it one time to enter calibration loop, for example by sending a "c" character thought the serial console.Also some useful function are used, like moving motor directly with analogWrite functions which all the calculations involved, this is a good point since no interrupts are used.This code also have the feature to calibrate the potentiometer coming from each motor.#define MAX_PULSE 2500 #define MIN_PULSE 560 /*---------------SERVO PIN DEFINITION------------------------*/ int m1 = 6;//FR int m2 = 5; int m3 = 4; int m4 = 28;//FL int m5 = 29; int m6 = 36; int m7 = 3;//BR int m8 = 2; int m9 = 1; int m10 = 7;//BL int m11 = 24; int m12 = 25; int m13 = 0;//BODY /*----------------- CALIBRATION PARAMETERS OF EACH SERVO -----------------*/ double lowLim[13] = {50, 30, 30, 50, 30, 30, 50, 30, 30, 50, 30, 30, 70}; double highLim[13] = {130, 150, 150, 130, 150, 150, 130, 150, 150, 130, 150, 150, 110}; double a[13] = { -1.08333, -1.06667, -1.07778, //FR -1.03333, 0.97778, 1.01111, //FL 1.03333, 1.05556, 1.07778, //BR 1.07500, -1.07778, -1.00000, //BL 1.06250 }; double b[13] = {179.0, 192.0, 194.5, //FR 193.0, 5.5, -7.5, //FL 7.0, -17.0, -16.0, //BR -13.5, 191.5, 157.0, //BL -0.875 }; double ae[13] = {0.20292, 0.20317, 0.19904 , 0.21256, -0.22492, -0.21321, -0.21047, -0.20355, -0.20095, -0.20265, 0.19904, 0.20337, -0.20226 }; double be[13] = { -18.59717, -5.70512, -2.51697, -5.75856, 197.29411, 202.72169, 185.96931, 204.11902, 199.38663, 197.89534, -5.33768, -32.23424, 187.48058 }; /*--------Corresponding angles you want to meassure at in your system-----------*/ double x1[13] = {120, 135, 90, 60, 135 , 90, 120, 135, 90, 60, 135, 90, 110}; //this will be the first angle you will meassure double x2[13] = {60, 90, 135, 120, 90, 135, 60, 90, 135, 120, 90, 135, 70};//this will be the second angle you will meassure for calibration /*--------You can define a motor tag for each servo--------*/ String motorTag[13] = {"FR coxa", "FR femur", "FR tibia", "FL coxa", "FL femur", "FL tibia", "BR coxa", "BR femur", "BR tibia", "BL coxa", "BL femur", "BL tibia", "Body angle" }; double ang1[13] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}; double ang2[13] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}; float xi[500]; float yi[500]; float fineAngle; float fineL; float fineH; int motorPin; int motor = 0; float calibrationAngle; float res = 1.0; float ares = 0.5; float bres = 1.0; float cres = 4.0; float rawAngle; float orawAngle; char cm; char answer; bool interp = false; bool question = true; bool swing = false; int i; double eang; int freq = 100; // PWM frecuency can be choosen here. void connectServos() { analogWriteFrequency(m1, freq); //FR coxa digitalWrite(m1, LOW); pinMode(m1, OUTPUT); analogWriteFrequency(m2, freq); //femur digitalWrite(m2, LOW); pinMode(m2, OUTPUT); analogWriteFrequency(m3, freq); //tibia digitalWrite(m3, LOW); pinMode(m3, OUTPUT); analogWriteFrequency(m4, freq); //FL coxa digitalWrite(m4, LOW); pinMode(m4, OUTPUT); analogWriteFrequency(m5, freq); //femur digitalWrite(m5, LOW); pinMode(m5, OUTPUT); analogWriteFrequency(m6, freq); //tibia digitalWrite(m6, LOW); pinMode(m6, OUTPUT); analogWriteFrequency(m7, freq); //FR coxa digitalWrite(m7, LOW); pinMode(m7, OUTPUT); analogWriteFrequency(m8, freq); //femur digitalWrite(m8, LOW); pinMode(m8, OUTPUT); analogWriteFrequency(m9, freq); //tibia digitalWrite(m9, LOW); pinMode(m9, OUTPUT); analogWriteFrequency(m10, freq); //FR coxa digitalWrite(m10, LOW); pinMode(m10, OUTPUT); analogWriteFrequency(m11, freq); //femur digitalWrite(m11, LOW); pinMode(m11, OUTPUT); analogWriteFrequency(m12, freq); //tibia digitalWrite(m12, LOW); pinMode(m12, OUTPUT); analogWriteFrequency(m13, freq); //body digitalWrite(m13, LOW); pinMode(m13, OUTPUT); } void servoWrite(int pin , double angle) { float T = 1000000.0f / freq; float usec = float(MAX_PULSE - MIN_PULSE) * (angle / 180.0) + (float)MIN_PULSE; uint32_t duty = int(usec / T * 4096.0f); analogWrite(pin , duty); } double checkLimits(double angle , double lowLim , double highLim) { if ( angle >= highLim ) { angle = highLim; } if ( angle <= lowLim ) { angle = lowLim; } return angle; } int motorInfo(int i) { enc1 , enc2 , enc3 , enc4 , enc5 , enc6 , enc7 , enc8 , enc9 , enc10 , enc11 , enc12 , enc13 = readEncoders(); if (i == 0) { rawAngle = enc1; motorPin = m1; } else if (i == 1) { rawAngle = enc2; motorPin = m2; } else if (i == 2) { rawAngle = enc3; motorPin = m3; } else if (i == 3) { rawAngle = enc4; motorPin = m4; } else if (i == 4) { rawAngle = enc5; motorPin = m5; } else if (i == 5) { rawAngle = enc6; motorPin = m6; } else if (i == 6) { rawAngle = enc7; motorPin = m7; } else if (i == 7) { rawAngle = enc8; motorPin = m8; } else if (i == 8) { rawAngle = enc9; motorPin = m9; } else if (i == 9) { rawAngle = enc10; motorPin = m10; } else if (i == 10) { rawAngle = enc11; motorPin = m11; } else if (i == 11) { rawAngle = enc12; motorPin = m12; } else if (i == 12) { rawAngle = enc13; motorPin = m13; } return rawAngle , motorPin; } void moveServos(double angleBody , struct vector anglesServoFR , struct vector anglesServoFL , struct vector anglesServoBR , struct vector anglesServoBL) { //FR anglesServoFR.tetta = checkLimits(anglesServoFR.tetta , lowLim[0] , highLim[0]); fineAngle = a[0] * anglesServoFR.tetta + b[0]; servoWrite(m1 , fineAngle); anglesServoFR.alpha = checkLimits(anglesServoFR.alpha , lowLim[1] , highLim[1]); fineAngle = a[1] * anglesServoFR.alpha + b[1]; servoWrite(m2 , fineAngle); anglesServoFR.gamma = checkLimits(anglesServoFR.gamma , lowLim[2] , highLim[2]); fineAngle = a[2] * anglesServoFR.gamma + b[2]; servoWrite(m3 , fineAngle); //FL anglesServoFL.tetta = checkLimits(anglesServoFL.tetta , lowLim[3] , highLim[3]); fineAngle = a[3] * anglesServoFL.tetta + b[3]; servoWrite(m4 , fineAngle); anglesServoFL.alpha = checkLimits(anglesServoFL.alpha , lowLim[4] , highLim[4]); fineAngle = a[4] * anglesServoFL.alpha + b[4]; servoWrite(m5 , fineAngle); anglesServoFL.gamma = checkLimits(anglesServoFL.gamma , lowLim[5] , highLim[5]); fineAngle = a[5] * anglesServoFL.gamma + b[5]; servoWrite(m6 , fineAngle); //BR anglesServoBR.tetta = checkLimits(anglesServoBR.tetta , lowLim[6] , highLim[6]); fineAngle = a[6] * anglesServoBR.tetta + b[6]; servoWrite(m7 , fineAngle); anglesServoBR.alpha = checkLimits(anglesServoBR.alpha , lowLim[7] , highLim[7]); fineAngle = a[7] * anglesServoBR.alpha + b[7]; servoWrite(m8 , fineAngle); anglesServoBR.gamma = checkLimits(anglesServoBR.gamma , lowLim[8] , highLim[8]); fineAngle = a[8] * anglesServoBR.gamma + b[8]; servoWrite(m9 , fineAngle); //BL anglesServoBL.tetta = checkLimits(anglesServoBL.tetta , lowLim[9] , highLim[9]); fineAngle = a[9] * anglesServoBL.tetta + b[9]; servoWrite(m10 , fineAngle); anglesServoBL.alpha = checkLimits(anglesServoBL.alpha , lowLim[10] , highLim[10]); fineAngle = a[10] * anglesServoBL.alpha + b[10]; servoWrite(m11 , fineAngle); anglesServoBL.gamma = checkLimits(anglesServoBL.gamma , lowLim[11] , highLim[11]); fineAngle = a[11] * anglesServoBL.gamma + b[11]; servoWrite(m12 , fineAngle); //BODY angleBody = checkLimits(angleBody , lowLim[12] , highLim[12]); fineAngle = a[12] * angleBody + b[12]; servoWrite(m13 , fineAngle); } double readEncoderAngles() { enc1 , enc2 , enc3 , enc4 , enc5 , enc6 , enc7 , enc8 , enc9 , enc10 , enc11 , enc12 , enc13 = readEncoders(); eang1 = ae[0] * enc1 + be[0]; eang2 = ae[1] * enc2 + be[1]; eang3 = ae[2] * enc3 + be[2]; eang4 = ae[3] * enc4 + be[3]; eang5 = ae[4] * enc5 + be[4]; eang6 = ae[5] * enc6 + be[5]; eang7 = ae[6] * enc7 + be[6]; eang8 = ae[7] * enc8 + be[7]; eang9 = ae[8] * enc9 + be[8]; eang10 = ae[9] * enc10 + be[9]; eang11 = ae[10] * enc11 + be[10]; eang12 = ae[11] * enc12 + be[11]; eang13 = ae[12] * enc13 + be[12]; return eang1 , eang2 , eang3 , eang4 , eang5 , eang6 , eang7 , eang8 , eang9 , eang10 , eang11 , eang12 , eang13; } void calibrationSecuence( ) { //set servos at their middle position at firstt for (int i = 0; i <= 12; i++) { rawAngle , motorPin = motorInfo(i); servoWrite(motorPin , 90); } // sensorOffset0 = calibrateContacts(); Serial.println(" "); Serial.println("_________________________________SERVO CALIBRATION ROUTINE_________________________________"); Serial.println("___________________________________________________________________________________________"); Serial.println("(*) Don"t send several caracter at the same time."); delay(500); Serial.println(" "); Serial.println("Keyboard: "x"-> EXIT CALIBRATION. "c"-> ENTER CALIBRATION."); Serial.println(" "i"-> PRINT INFORMATION. "); Serial.println(" "); Serial.println(" "n"-> CHANGE MOTOR (+). "b" -> CHANGE MOTOR (-)."); Serial.println(" "m"-> START CALIBRATION."); Serial.println(" "q"-> STOP CALIBRATION."); Serial.println(" "); Serial.println(" "r"-> CHANGE RESOLUTION."); Serial.println(" "p"-> ADD ANGLE. "o"-> SUBTRACT ANGLE. "); Serial.println(" "s"-> SAVE ANGLE."); delay(500); Serial.println(" "); Serial.println("---------------------------------------------------------------------------------------------------"); Serial.print("SELECTED MOTOR: "); Serial.print(motorTag[motor]); Serial.print(". SELECTED RESOLUTION: "); Serial.println(res); while (CAL == true) { if (Serial.available() > 0) { cm = Serial.read(); if (cm == "x") { Serial.println("Closing CALIBRATION program..."); CAL = false; secuence = false; startDisplay(PAGE); angleBody = 90; anglesIKFR.tetta = 0.0; anglesIKFR.alpha = -45.0; anglesIKFR.gamma = 90.0; anglesIKFL.tetta = 0.0; anglesIKFL.alpha = -45.0; anglesIKFL.gamma = 90.0; anglesIKBR.tetta = 0.0; anglesIKBR.alpha = 45.0; anglesIKBR.gamma = -90.0; anglesIKBL.tetta = 0.0; anglesIKBL.alpha = 45.0; anglesIKBL.gamma = -90.0; } else if (cm == "i") { // + Serial.println(" "); Serial.println("---------------------------------------------------------------------------------------------------"); Serial.println("---------------------------------------------------------------------------------------------------"); Serial.println("(*) Don"t send several caracter at the same time."); delay(500); Serial.println(" "); Serial.println("Keyboard: "x"-> EXIT CALIBRATION. "c"-> ENTER CALIBRATION."); Serial.println(" "i"-> PRINT INFORMATION. "); Serial.println(" "); Serial.println(" "n"-> CHANGE MOTOR (+). "b" -> CHANGE MOTOR (-)."); Serial.println(" "m"-> START CALIBRATION."); Serial.println(" "q"-> STOP CALIBRATION."); Serial.println(" "); Serial.println(" "r"-> CHANGE RESOLUTION."); Serial.println(" "p"-> ADD ANGLE. "o"-> SUBTRACT ANGLE. "s"-> SAVE ANGLE."); Serial.println(" "); delay(500); Serial.println(" "); Serial.println("---------------------------------------------------------------------------------------------------"); Serial.println(" "); Serial.print("SELECTED MOTOR: "); Serial.print(motorTag[motor]); Serial.print(". SELECTED RESOLUTION: "); Serial.println(res); Serial.println("Actual parameters of the motor: "); Serial.print("High limit: "); Serial.print(highLim[motor]); Serial.print(" Low limit: "); Serial.print(lowLim[motor]); Serial.print(" Angle 1: "); Serial.print(ang1[motor]); Serial.print(" Angle 2: "); Serial.println(ang2[motor]); Serial.println("---------------------------------------------------------------------------------------------------"); } else if (cm == "m") { // + secuence = true; } else if (cm == "s") { // + } else if (cm == "n") { // + motor++; if (motor >= 13) { motor = 0; } Serial.print("SELECTED MOTOR: "); Serial.println(motorTag[motor]); } else if (cm == "b") { // + motor--; if (motor < 0) { motor = 13 - 1; } Serial.print("SELECTED MOTOR: "); Serial.println(motorTag[motor]); } else if (cm == "r") { // + if (res == ares) { res = bres; } else if (res == bres) { res = cres; } else if (res == cres) { res = ares; } Serial.print("SELECTED RESOLUTION: "); Serial.println(res); } } if (secuence == true) { Serial.print("Starting secuence for motor: "); Serial.println(motorTag[motor]); for (int i = 0; i <= 30; i++) { delay(20); Serial.print("."); } Serial.println("."); while (question == true) { unsigned long currentMicros = micros(); if (currentMicros - previousMicros >= 100000) { previousMicros = currentMicros; if (Serial.available() > 0) { answer = Serial.read(); if (answer == "y") { question = false; interp = true; secuence = true; } else if (answer == "n") { question = false; interp = false; secuence = true; } else { Serial.println("Please, select Yes(y) or No(n)."); } } } } answer = "t"; question = true; if (interp == false) { Serial.println("___"); Serial.println(" | Place motor at 1ts position and save angle"); Serial.println(" | This position can be the higher one"); rawAngle , motorPin = motorInfo(motor); calibrationAngle = 90; //start calibration at aproximate middle position of the servo. while (secuence == true) { /* find first calibration angle */ if (Serial.available() > 0) { cm = Serial.read(); if (cm == "p") { // + Serial.print(" | +"); Serial.print(res); Serial.print(" : "); calibrationAngle = calibrationAngle + res; servoWrite(motorPin , calibrationAngle); Serial.println(calibrationAngle); } else if (cm == "o") { // - Serial.print(" | -"); Serial.print(res); Serial.print(" : "); calibrationAngle = calibrationAngle - res; servoWrite(motorPin , calibrationAngle); Serial.println(calibrationAngle); } else if (cm == "r") { // + if (res == ares) { res = bres; } else if (res == bres) { res = cres; } else if (res == cres) { res = ares; } Serial.print("SELECTED RESOLUTION: "); Serial.println(res); } else if (cm == "q") { // quit secuence secuence = false; Serial.println(" | Calibration interrupted!!"); } else if (cm == "s") { // save angle ang1[motor] = calibrationAngle; secuence = false; Serial.print(" | Angle saved at "); Serial.println(calibrationAngle); } } } if (cm == "q") { Serial.println(" |"); } else { secuence = true; Serial.println("___"); Serial.println(" | Place motor at 2nd position and save angle"); Serial.println(" | This position can be the lower one"); } while (secuence == true) { /* find second calibration angle */ if (Serial.available() > 0) { cm = Serial.read(); if (cm == "p") { // + Serial.print(" | +"); Serial.print(res); Serial.print(" : "); calibrationAngle = calibrationAngle + res; servoWrite(motorPin , calibrationAngle); Serial.println(calibrationAngle); } else if (cm == "o") { // - Serial.print(" | -"); Serial.print(res); Serial.print(" : "); calibrationAngle = calibrationAngle - res; servoWrite(motorPin , calibrationAngle); Serial.println(calibrationAngle); } else if (cm == "r") { // + if (res == ares) { res = bres; } else if (res == bres) { res = cres; } else if (res == cres) { res = ares; } Serial.print("SELECTED RESOLUTION: "); Serial.println(res); } else if (cm == "q") { // quit secuence secuence = false; Serial.println(" | Calibration interrupted!!"); } else if (cm == "s") { // save angle ang2[motor] = calibrationAngle; secuence = false; Serial.print(" | Angle saved at "); Serial.println(calibrationAngle); } } } /*--------------------start calibration calculations------------------*/ if (cm == "q") { Serial.println("___|"); Serial.println("Calibration finished unespected."); Serial.println(" Select another motor."); Serial.print("SELECTED MOTOR: "); Serial.print(motorTag[motor]); Serial.print(". SELECTED RESOLUTION: "); Serial.println(res); } else { Serial.println("___"); Serial.println(" |___"); Serial.print( " | | Interpolating for motor: "); Serial.println(motorTag[motor]); secuence = true; //real angle is calculated interpolating both angles to a linear relation. a[motor] = (ang2[motor] - ang1[motor]) / (x2[motor] - x1[motor]); b[motor] = ang1[motor] - x1[motor] * (ang2[motor] - ang1[motor]) / (x2[motor] - x1[motor]); Serial.println(" | |"); } interp = true; } /*---------------------------make swing movement to interpolate motor encoder-----*/ if (interp == true and secuence == true) { delay(200); double x; int k = 0; int stp = 180; swing = true; i = 0; orawAngle , motorPin = motorInfo(motor); previousMicros = 0; while (swing == true) { // FIRST unsigned long currentMicros = micros(); if (currentMicros - previousMicros >= 10000) { // save the last time you blinked the LED previousMicros = currentMicros; x = x2[motor]; calibrationAngle = a[motor] * x + b[motor]; servoWrite(motorPin , calibrationAngle); rawAngle , motorPin = motorInfo(motor); if ((i % 3) == 0) { yi[k+1] = x; xi[k] = rawAngle; Serial.print(" | | Real ang: "); Serial.print(x); Serial.print(" -> Servo ang: "); Serial.print(calibrationAngle); Serial.print(" Enc: "); Serial.println(rawAngle); k++; } if (i >= stp) { swing = false; } i++; } } swing = true; i = 0; while (swing == true) { // moving unsigned long currentMicros = micros(); if (currentMicros - previousMicros >= 10000) { // save the last time you blinked the LED previousMicros = currentMicros; x = x2[motor] + float(i) * (x1[motor] - x2[motor]) / stp; calibrationAngle = a[motor] * x + b[motor]; servoWrite(motorPin , calibrationAngle); rawAngle , motorPin = motorInfo(motor); if ((i % 6) == 0) { yi[k+1] = x; xi[k] = rawAngle; Serial.print(" | | Real ang: "); Serial.print(x); Serial.print(" -> Servo ang: "); Serial.print(calibrationAngle); Serial.print(" Enc: "); Serial.println(rawAngle); k++; } if (i >= stp) { swing = false; } i++; } } swing = true; i = 0; while (swing == true) { // SECOND unsigned long currentMicros = micros(); if (currentMicros - previousMicros >= 10000) { // save the last time you blinked the LED previousMicros = currentMicros; x = x1[motor]; calibrationAngle = a[motor] * x + b[motor]; servoWrite(motorPin , calibrationAngle); rawAngle , motorPin = motorInfo(motor); if ((i % 3) == 0) { yi[k+1] = x; xi[k] = rawAngle; Serial.print(" | | Real ang: "); Serial.print(x); Serial.print(" -> Servo ang: "); Serial.print(calibrationAngle); Serial.print(" Enc: "); Serial.println(rawAngle); k++; } if (i >= stp) { swing = false; } i++; } } swing = true; i = 0; while (swing == true) { // moving unsigned long currentMicros = micros(); if (currentMicros - previousMicros >= 10000) { // save the last time you blinked the LED previousMicros = currentMicros; x = x1[motor] + float(i) * (x2[motor] - x1[motor]) / stp; calibrationAngle = a[motor] * x + b[motor]; servoWrite(motorPin , calibrationAngle); rawAngle , motorPin = motorInfo(motor); if ((i % 6) == 0) { yi[k+1] = x; xi[k] = rawAngle; Serial.print(" | | Real ang: "); Serial.print(x); Serial.print(" -> Servo ang: "); Serial.print(calibrationAngle); Serial.print(" Enc: "); Serial.println(rawAngle); k++; } if (i >= stp) { swing = false; } i++; } } swing = true; i = 0; while (swing == true) { // FIRST unsigned long currentMicros = micros(); if (currentMicros - previousMicros >= 10000) { // save the last time you blinked the LED previousMicros = currentMicros; x = x2[motor]; calibrationAngle = a[motor] * x + b[motor]; servoWrite(motorPin , calibrationAngle); rawAngle , motorPin = motorInfo(motor); if ((i % 3) == 0) { yi[k+1] = x; xi[k] = rawAngle; Serial.print(" | | Real ang: "); Serial.print(x); Serial.print(" -> Servo ang: "); Serial.print(calibrationAngle); Serial.print(" Enc: "); Serial.println(rawAngle); k++; } if (i >= stp) { swing = false; } i++; } } swing = true; i = 0; while (swing == true) { // moving unsigned long currentMicros = micros(); if (currentMicros - previousMicros >= 10000) { // save the last time you blinked the LED previousMicros = currentMicros; x = x2[motor] + float(i) * (x1[motor] - x2[motor]) / stp; calibrationAngle = a[motor] * x + b[motor]; servoWrite(motorPin , calibrationAngle); rawAngle , motorPin = motorInfo(motor); if ((i % 6) == 0) { yi[k+1] = x; xi[k] = rawAngle; Serial.print(" | | Real ang: "); Serial.print(x); Serial.print(" -> Servo ang: "); Serial.print(calibrationAngle); Serial.print(" Enc: "); Serial.println(rawAngle); k++; } if (i >= stp) { swing = false; } i++; } } swing = true; i = 0; while (swing == true) { // SECOND unsigned long currentMicros = micros(); if (currentMicros - previousMicros >= 10000) { // save the last time you blinked the LED previousMicros = currentMicros; x = x1[motor]; calibrationAngle = a[motor] * x + b[motor]; servoWrite(motorPin , calibrationAngle); rawAngle , motorPin = motorInfo(motor); if ((i % 3) == 0) { yi[k+1] = x; xi[k] = rawAngle; Serial.print(" | | Real ang: "); Serial.print(x); Serial.print(" -> Servo ang: "); Serial.print(calibrationAngle); Serial.print(" Enc: "); Serial.println(rawAngle); k++; } if (i >= stp) { swing = false; } i++; } } Serial.println(" | | Interpolation finished!"); /*-------Calculate linear interpolation of the encoder from 60 meassures done in swing------*/ double sx = 0; double sy = 0; double sx2 = 0; double sy2 = 0; double sxy = 0; double xmean = 0; double ymean = 0; int n = 300; for (int i = 0 ; i < n ; i++) { sx += xi[i+10]; sy += yi[i+10]; sx2 += xi[i+10] * xi[i+10]; sy2 += yi[i+10] * yi[i+10]; sxy += xi[i+10] * yi[i+10]; } ae[motor] = (n * sxy - sx * sy) / (n * sx2 - sx * sx); //sxy / sx2; // be[motor] = (sy - ae[motor] * sx) / n; //ymean - ae[motor] * xmean; Serial.println(" | | Moving back to ZERO position."); // turn the motor back to middle position swing = true; i = 0; while (swing == true) { unsigned long currentMicros = micros(); if (currentMicros - previousMicros >= 10000) { // save the last time you blinked the LED previousMicros = currentMicros; x = x1[motor] + float(i) * (90 - x1[motor]) / 60; calibrationAngle = a[motor] * x + b[motor]; servoWrite(motorPin , calibrationAngle); rawAngle , motorPin = motorInfo(motor); eang = ae[motor] * rawAngle + be[motor]; if ((i % 4) == 0) { Serial.print(" | | Servo ang: "); Serial.print(calibrationAngle); Serial.print(" -> Real ang: "); Serial.print(x); Serial.print(" -> Encoder ang: "); Serial.println(eang); } if (i >= 60) { swing = false; } i++; } } Serial.println("___|___|"); Serial.println(" | "); Serial.println("___"); Serial.println(" | Calibration finished satisfactory. Results data:"); Serial.print(" | HIGH lim: "); Serial.print(highLim[motor]); Serial.print(" LOW lim: "); Serial.println(lowLim[motor]); Serial.print(" | angle 1: "); Serial.print(ang1[motor]); Serial.print(" angle 2 "); Serial.println(ang2[motor]); Serial.print(" | Regression Motor a: "); Serial.print(a[motor], 5); Serial.print(" b: "); Serial.println(b[motor], 5); Serial.print(" | Regression Encoder a: "); Serial.print(ae[motor], 5); Serial.print(" b: "); Serial.println(be[motor], 5); Serial.println(" |"); Serial.println(" | ______________________________________________________________"); Serial.println(" | | |"); Serial.println(" | | This code won"t be able to save the updated parameters |"); Serial.println(" | | once the robot is shutted down. |"); Serial.println(" | | |"); Serial.println(" | | Please, write down the results |"); Serial.println(" | | and save them in the definition of each variable. |"); Serial.println(" | |_____________________________________________________________|"); Serial.println(" |"); Serial.println("___|"); Serial.println(" Select another motor."); Serial.print("SELECTED MOTOR: "); Serial.print(motorTag[motor]); Serial.print(". SELECTED RESOLUTION: "); Serial.println(res); } interp = false; secuence = false; } } SAFE = false; Serial.println("Calibration killed"); } // END OF CALIBRATION

Furniture industry: various types of doors, windows, cabinets, shelves, tables, chairs, sofas, couches, stools, benches, beds, desks, night stands, bunks, cupboard, tea boards.

Decoration industry: door frames, handrails, building columns, pillars, table legs, chair legs, photo frames, mirror frames, screens, lights, holiday decorations.

Craft industry: artworks, gifts, souvenirs, clock frames, stamps, badges, medals, trophies, holiday ornaments Advertising industry: advertising signs, logos, labels, 3D letters and numbers, double color boards, acrylic nameplates, company names, LED lights Mold industry: wood mold, foam mold and metal mold

Musical instrument industry: 3D surface carving, shape cutting, guitar, bass, violin, viola, violoncello, erhu, and other string instrument Other: printed circuit boards, isolated materials, engraving or routing of home appliance enclosures, EVA packages of tools and devices, engraving or routing of the lining material of medical equipment, electronics or other containers.

Using the right calibration board to calibrate the scanner for accuracy ensures you get the best scanning results for a particular scanning volume. Calibration boards are optimized to work with FlexScan3D.

* pL SOLUTIONS Shanghai Co. Ltd is part of a network of locally owned, independent representatives and service specialists dedicated exclusively to the sales, service, and support of CNC rotary tables designed and manufactured by the Swiss firm Peter Lehmann AG (pL)

* pL SOLUTIONS India/SEAis part of a network of locally owned, independent distributors and service specialists dedicated exclusively to the sales, service, and support of CNC rotary tables designed and manufactured by the Swiss firm Peter Lehmann AG (pL)

* pL SOLUTIONS Italia is part of a network of locally owned, independent distributors and service specialists dedicated exclusively to the sales, service, and support of CNC rotary tables designed and manufactured by the Swiss firm Peter Lehmann AG (pL)

* pL SOLUTIONS Japan is part of a network of locally owned, independent distributors and service specialists dedicated exclusively to the sales, service, and support of CNC rotary tables designed and manufactured by the Swiss firm Peter Lehmann AG (pL)

* pL SOLUTIONS USAis part of a network of locally owned, independent distributors and service specialists dedicated exclusively to the sales, service, and support of CNC rotary tables designed and manufactured by the Swiss firm Peter Lehmann AG (pL)

* pL SOLUTIONS India/SEA is part of a network of locally owned, independent distributors and service specialists dedicated exclusively to the sales, service, and support of CNC rotary tables designed and manufactured by the Swiss firm Peter Lehmann AG (pL)

* pL SOLUTIONS USA is part of a network of locally owned, independent distributors and service specialists dedicated exclusively to the sales, service, and support of CNC rotary tables designed and manufactured by the Swiss firm Peter Lehmann AG (pL)

* pL SOLUTIONS India/SEAis part of a network of locally owned, independent distributors and service specialists dedicated exclusively to the sales, service, and support of CNC rotary tables designed and manufactured by the Swiss firm Peter Lehmann AG (pL)

* pL SOLUTIONS South Korea is part of a network of locally owned, independent distributors and service specialists dedicated exclusively to the sales, service, and support of CNC rotary tables designed and manufactured by the Swiss firm Peter Lehmann AG (pL)

* pL SOLUTIONS India/SEA is part of a network of locally owned, independent distributors and service specialists dedicated exclusively to the sales, service, and support of CNC rotary tables designed and manufactured by the Swiss firm Peter Lehmann AG (pL)

* pL SOLUTIONS USAis part of a network of locally owned, independent distributors and service specialists dedicated exclusively to the sales, service, and support of CNC rotary tables designed and manufactured by the Swiss firm Peter Lehmann AG (pL)

* pL SOLUTIONS India/SEAis part of a network of locally owned, independent distributors and service specialists dedicated exclusively to the sales, service, and support of CNC rotary tables designed and manufactured by the Swiss firm Peter Lehmann AG (pL)

pL ADDITIVE is a division of pL LEHMANN. With over 50 years" experience in machining production and as a manufacturer of CNC rotary tables for over 40 years, we are closely familiar with the demands placed on industrial production processes. The need for a zero-point clamping system was inspired by the fact that many workpieces made by LPBF technology need to be post-machined for mating surfaces, threads, surfaces or other precision contours. This synergy will allow the user not only to produce the 3D-printed workpieces, but also to post-machine and finish it in an efficient, precise and reliably manner. Here we focus mainly on the following post-processing methods:

Together with a well-known manufacturer, the development for a suitable zero point positioning clamping system AM-LOCK was started. It soon became clear that the installation space itself (construction shaft, construction platform) presents unresolved challenges for the manufacturers and the users. Also in this specific environment, pL ADDITIVE has acquired expertise in order to be able to advise you in the best possible way.

A digital caliper has many applications in 3D printing. It’s useful for checking the precision of your prints, and you can also use it to dimension parts to replicate in CAD software. Calipers are also handy for checking filament measurements – as filaments aren’t often manufactured to exact measurements. Simply measure it at a few different positions, average the readings, then adjust the filament diameter in your slicing software if necessary.

It’s a good idea to have a selection of sandpaper in a variety of different grits. These will all prove useful when you’re post-processing your 3D prints. Our recommendation? Have a selection from coarse (220 grit) to fine (1000 grit), and invest in well-known brands such as 3M, as they’re likely to last you longer than cheaper, inferior types.

Most people already own a good selection of screwdrivers and hex keys. If you don’t, it’s worthwhile getting some, as you’ll periodically need to re-tighten the gantry screws and the stepper motors of your 3D printer. Hex nuts and bolts are widely used in 3D printer assembly, so it’s also a wise idea to have a set of hex key screwdrivers and wrenches.