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Arduino Reptile Pulse Proportional Thermsotat

Hi, I have kept many reptiles in the past and use this type of thermostat control with any of my non-light emitting heat sources such as ceramics, heat mats etc but these thermostats are pricey for every setup. An idea I had was to maybe incorporate an Arduino since I have one lying round to be able to control multiple input/outputs for more than one tank, but i do not know how to go about building one and what pulse proportional means. I have used Arduino before and familiar with C programming but not done much with controlling AC electrics other than either on/off using relays (ideal for simple thermostats tho like MatStats from livingearth). So would it be as easy as to find a PWM AC controller and make the Arduino change the duty cycle depending on how close the temperature actually is compared to the set point? Or would I need to use PID control? Any ideas would be great. 

Topic by rowly747    |  last reply


unfinished,5 DOF Robotic Mechanical ARM

5 DOF Robotic Mechanical ARM Required Material of project:- 1. Basic Servo Tower pro 9g*4 2. Header pins Male female*2 3. Arduino Nano*1 4.10kΩ Resistor resistance*2 5. Trimmer Potentiometer track Linear; maximum resistance 10kΩ*4 6. Tactile push button*2 7. Blank circuit board*1 8. Acrylic strips for Robot & potentiometer body*2 9. Wires, Button, Switch 10.Balsa wood, Metal, Plastic Procedure:- Arrange all necessary items.. Please go through the attached images  for better understanding.. I divide whole project in two parts 1) Servo Motor assembly 2) Potentiometer assembly 1) Servo motor assembly: – Servo motor as J1, J2, J3, J4 fix the servo motors as shown in image use 3M tape to glue servo, use thin flexible plastic strip to make griper, make hole in center of each finger tie thread in that hole pass this thread from center hole and tie knot at the other end of thread with 4th servo motor’s knob, as you stretch thread finger get close vise versa. Fix whole arrangement on strong rigid base. 2) Potentiometer assembly: – Fix potentiometer as shown in figure name potentiometer as do previous R3, R4, R5, R6 this time place R6 separately for easy access this potentiometer control gripper to pick and place. Potentiometer arrangement symmetry must be same as servo arm. Fix whole arrangement on strong rigid base. Moving a little bolt from one side to the other side:- 1. Actuators / output devices: 4 micro servos 2. Control method: controlled by a PIC16F690       assembler firmware 3. CPU: PIC16f690 micro controller 4. Operating system: self made assembler code 5. Power source: 4.8V to 6V from 4 battery cells 6. Programming language: PIC Assembler 7. Sensors / input devices: teach in system with                         4 potentiometers       Making Processer:- The Potis are standard types and are screwed to the white plastic parts with their nuts. The axles are pressed into the transparent plastic part. The handle to move the teach-in-arm is a M3-Spacer and the socket is a plastic part with is normally used to fix balloons on a stick to hold it.                     move the motor itself by hand a little force is needed due to its permanent magnets, which create a small holding force. But inside the servo a lot of gears increase the force which you have to apply. If you move the servo by hand, you have to apply a much higher force. If you overcome the motors holding force, it starts to rotate an acts as a flywheel. So moving a servo by hand needs a high torque and its not easy to turn it to the position where you want it. ( Fan control modules for engine cooling of real cars have some extra parts to clamp the voltage which is generated, when you drive at higher speeds. In that case the fan works like a windmill and creates higher voltages than normal inside the power stage of the module.) And there were also a lot of other "problems" which had to be solved using my PIC Controllers. i.e. self made electronics for a RC-Excavator which works similar to the digital system used in slot cars. To replace a lot of wires between the rotating part of the excavator and the track unit, a small PIC 12F629 reads the pulses from up to 5 channels of a RC-Receiver and leads their information via a 2 wire connection to a second PIC12F629. At the second board the power is separated from the data. The PIC is reading the data, and generates the PWM output for the 5 Servo output connector. the 2 wire connection is made with a cheap 6,3mm mono microphone plug which is also used as the axle for the rotating part. The arm of the excavator is also powered by standard servos and so it was necessary to change the control behavior from proportional to integral so that the servos move like real hydraulic cylinders which are controlled by valves. I used the same 12F629 type for that job and added some features like adjustable limit positions and starting point programmable by one jumper, and automatic return to park position when missing the pulses for some seconds. The Software is simple:- Its working like a servotester for four axis. That means, every poti is connected to an analog in of the controller and all servos are connected to GPIOs. The controller reads each poti, does some scaling, so that the angle of the poti equals to the angle of the axis and finally he creates the PWM output 1-2ms pulse every 20ms for all servos. Teach mode:- After a reset the robot arm follows the teach in arm while simple mapping the analog inputs every 25ms to the servo motors. Pressing the button stores each servo position in a array. Play mode: The sketch reads the array step by step and moves the robot arm. For cool looking movements I added a routine calculates different micro steps for each servo to have moving start and end sync on all axis. Also added a ramp for soft increase/decrease velocity. Shorter travel distances the robot does slow, longer distances with faster speed.           The program moves the servos at full speed to the next position and a short delay time after each command allows all of the servos to reach their final position. That means that it is possible to increase the speed a little bit more by doing some fine tuning of the delay times after each command. The final thing which is still not implemented is the routine which saves the "Teach In" data 5 or 10 times per second, so that the controller is able to replay it in a loop with the original speed or with a lower or higher speed. Electrical Connection:- Provide separate power supply (5V DC 1amps) to the Servo motors . Don’t forget to short ground of both power source ( arduino + servo) 5 DOF Robotic Mechanical ARM :- 1. Use of Fiber on upper side 2. wooden spoon is a part of side body 3. cable tie *12 pieces use the robotic. 4. Some pices of wires 5. use scraw*4 6. Glue 7. some small clips Because to attached body 8. small size of plastic box 9. One pieces of  square fiber stand and one pieces small & medium  circular fiber  10.  L293D Motor Driver IC+IC Base KG143 11. Generic Elementz High Quality Nickel Plated 24*18 Points Bread Board*(2 pieces) and one plastic 12. Push Button Switch. Play Mode version 1.1 The gripper input is used to set the delay (0,1,3,15,60,300 seconds) after a loop is done. The switch (it was left from the project start) pauses the robot.        Thanks you:

Topic by aarif1234  


500W electric scooter control and instrumentation with Arduino mega

1. Introduction DC 500W motor control with an Arduino mega to limit starting current and to vary the speed of the scooter. The battery is in 24V, 10A.h. The following table summarizes their characteristics: https://i58.servimg.com/u/f58/17/56/35/17/a014.jpg https://i58.servimg.com/u/f58/17/56/35/17/a111.jpg 2. Bibliography: Link download : sketch_escooter_feed_back_reel_V1.ino https://drive.google.com/file/d/0B_fB3GAsM02FSlRTWHdyRkhuUW8/view?usp=sharing escooter_ampli_SIMULINK.mdl https://drive.google.com/file/d/0B_fB3GAsM02FOW9OdmlhdDhJZGc/view?usp=sharing escooter feed back ISIS.DSN https://drive.google.com/file/d/0B_fB3GAsM02FOXdRWFN5OWRMQkE/view?usp=sharing youtube  :  "study trotinette electric e-scooter 100W et 350W, wiring"  youtube https://www.youtube.com/watch?v=QqJ2-YiE8Tg&index;=75&list;=PLfZunVn_gcq7EOurXuWU2sRFmh6CbiUiL Article: «Study of electric scooters 100W and 500W (Arduino), Revue 3EI 2017» Pdf? Book «I realize my electric vehicle» at DUNOD 3. Open loop program To test the programming, we simulate the program in ISIS, as can be seen in the following figure. In addition, we have an LCD display to display data (duty cycle corresponding to the PWM at 32Khz, motor current, motor voltage, action on the pushbuttons, 4 push buttons are used. BP1 to manually increment the duty cycle, BP2 decrement it. BP3 set the duty cycle to 0, corresponding to the brake contact. The speed of the motor is practically proportional to the duty cycle https://i58.servimg.com/u/f58/17/56/35/17/a211.jpg We made our own current amplifier called a step-down chopper but it is possible to buy a shield There are many cards for Arduino to control DC motors especially of low powers and also of great powers as can be observed on the following links.http://www.robotpower.com/products/MegaMotoPlus_info.html http://www.robotshop.com/en/dc-motor-driver-2-15a.html https://www.pololu.com/file/0J51/vnh3sp30.pdf https://i58.servimg.com/u/f58/17/56/35/17/a310.jpg But all these chopper shields measure the current internally but there is no current limitation. In order to have a current limitation, an analog current loop is required using specialized AOP or IC or a fast digital current loop. But what should be the value of the limitation current? The choice of the current value is normally for the 1-hour operation service in order to be able to carry out relatively long climbs without reaching the critical temperature of the engine. In our case, the limitation current must be Limiting motor = Power / Upper battery = 500W / 24V = 20A In addition, the power transistor of the chopper can only support 50A in our case. But in open loop, it has no current regulation, so as not to exceed the maximum current, a ramp of the duty cycle will be used. A 0.1 second interruption routine will be used to measure the voltage of the current (sample measurement, sample). This sampling time is arbitrary but does not allow to be faster than the rise time of the current because the electric time constant of the motor is L / R = 1.5 ms. Open loop operation with a 25.5s (8bit) ramp and 0.1s interrupt routine provides a good understanding of the operation of a DC motor drive. The display will only be done every 0.2s to have a stability of the digits on the screen. In addition, a digital filtering will be done on the current and the voltage on 4 values therefore on 0.4s. [b] Algo open loop [/b] Interrupt Routine All 0.1S Read voltage and current Loop loop (push button scan) If BP1 = 1 then increment PWM If BP2 = 1 then decrement PWM If BP3 = 1 then PWM = 0 Displaying variables every 0.2s Code: [Select] // include the library code: #include #include #include #define SERIAL_PORT_LOG_ENABLE 1 #define Led     13       // 13 for the yellow led on the map #define BP1     30       // 30 BP1 #define BP2     31       // 31 BP2           #define BP3     32       // 32 BP3 #define LEDV    33       // 33 led #define LEDJ    34       // 34 led #define LEDR    35       // 35 led #define relay   36       // 36 relay #define PWM10    10      //11   timer2    LiquidCrystal lcd(27, 28, 25, 24, 23, 22); // RS=12, Enable=11, D4=5, D5=4, D6= 3, D7=2, BPpoussoir=26 // Configuring variables unsigned   int UmoteurF = 0;  // variable to store the value coming from the sensor unsigned   int Umoteur = 0; unsigned   int Umoteur2 = 0; unsigned   int Umoteur3 = 0; unsigned   int Umoteur4 = 0; unsigned   int ImoteurF = 0;  unsigned   int Imoteur = 0; unsigned   int Imoteur2 = 0; unsigned   int Imoteur3 = 0; unsigned   int Imoteur4 = 0;            byte Rcy=0 ;    // 8bit duty cycle unsigned    int temps; // the setup function runs once when you press reset or power the board void setup() {   pinMode(Led, OUTPUT);   // Arduino card   pinMode(LEDV, OUTPUT);   pinMode(LEDR, OUTPUT);   pinMode(LEDJ, OUTPUT);   pinMode (PWM10,OUTPUT);     // Pin (10) output timer2   //  digitalWrite(LEDV,LOW);   Timer1.initialize(100000);         // initialize timer1, and set a 0,1 second period =>  100 000   Timer1.attachInterrupt(callback);  // attaches callback() as a timer overflow interrupt   lcd.begin(20, 4);    Serial1.begin(9600);   TCCR2B = (TCCR2B & 0b11111000) | 0x01;         //pin 10  32khz    http://playground.arduino.cc/Main/TimerPWMCheatsheet                                                   //http://www.pobot.org/Modifier-la-frequence-d-un-PWM.html   //   analogWriteResolution(bits)      https://www.arduino.cc/en/Reference/AnalogWriteResolution lcd.setCursor(0,1); lcd.print("Rcy"); lcd.setCursor(10,1); lcd.print("Um"); lcd.setCursor(5,1); lcd.print("Im"); lcd.setCursor(10,1); lcd.print("Um"); lcd.setCursor(20,1); // 4 lines display * 20 characters lcd.print("BP1+"); lcd.setCursor(25,1); lcd.print("BP2-"); lcd.setCursor(29,1); lcd.print("BP3=0"); } // Interruptions  tous les 0.1s void callback()  { temps++; //toogle state ledv for check   if ( digitalRead(LEDV)== 1 ) {digitalWrite(LEDV,LOW);}     else {digitalWrite(LEDV,HIGH);}     analogWrite(PWM10,Rcy);   // frequency Umoteur=analogRead(A0); Imoteur=analogRead(A1); Imoteur2=Imoteur; Imoteur3=Imoteur2; Imoteur4=Imoteur3; ImoteurF=(Imoteur4+Imoteur3+Imoteur2+Imoteur)/4 ; Umoteur2=Umoteur; Umoteur3=Umoteur2; Umoteur4=Umoteur3; UmoteurF=(Umoteur4+Umoteur3+Umoteur2+Umoteur)/4 ;   }// End routine // Loop corresponding to main function void loop() {    // BP + LED   if ((digitalRead(BP1))==1) {     lcd.setCursor(20,0);      // Column line     lcd.print("BP1");     digitalWrite(LEDR, LOW);        digitalWrite(LEDJ, LOW);     Rcy++;                        // PWM incrementation     if ( Rcy>254)  {Rcy=254;}     delay(100);               //8bits * 100ms = 25S increment 25ssecond slope     }        if ((digitalRead(BP2))==1) {     lcd.setCursor(20,0);     lcd.print("BP2");             Rcy--;      if ( Rcy<2)  {Rcy=2;}  // PWM almost at 0, engine stop         delay(100);      digitalWrite(LEDR, HIGH);     digitalWrite(LEDJ, HIGH);     }   if ((digitalRead(BP3))==1) {     lcd.setCursor(20,0);     lcd.print("BP3");      Rcy=2;               // PWM almost at 0, engine stop     } if (temps>=2)  { lcd.setCursor(0,0); lcd.print("                "); // Erase line lcd.setCursor(0,0);     lcd.print(Rcy); lcd.setCursor(5,0); ImoteurF=(ImoteurF)/20;     //resistance (5/1024)*(10/0.25ohm) si ACS712 66mV/A                            // For resistance 1ohm (ImoteurF) / 20; Simulation 5/25 lcd.print(ImoteurF); lcd.setCursor(10,0); UmoteurF=UmoteurF*10/38;                              //10/38   10/30 simula if (Umoteur>ImoteurF){UmoteurF=UmoteurF-ImoteurF;  }  //U-R*I lcd.print(UmoteurF); temps=0; }// End if time    } // End loop https://i58.servimg.com/u/f58/17/56/35/17/dsc_0614.jpg Since there is a limit of 9000 characters in the forum below Open loop program feature previous The interrupt routine lasts only 250 microseconds, the loop of the main program which scans the action of push buttons is 13micros and the display time of all data is 11ms. Thus, it is possible to improve the sampling period and thus the speed of the regulation of the current. The Arduino makes it possible to make the instrumentation of the scooter so to know the power, the consumption in Ah and Wh, to measure the speed, to know the consumption according to Wh / km, to measure the temperature of the engine, Have a safe operation. But for now we will see how to limit the current 4. Closed loop program, limited current control The sampling period will increase to 0.01 seconds (interrupt routine) If the current is less than the desired value, then the duty cycle can be increased or decreased to the desired value which is the setpoint. On the other hand, if the motor current is greater than the limiting value, there is a rapid decrease in the duty cycle. So as not to exceed the value of the duty cycle if it is saturated to 254 maximum and to the minimum value 6. Code: [Select] if (Imoteur<4000)                    // No current limitation at (20A * 10) * 20 = 4000   {if (consigne>Rcy)   {Rcy=Rcy+1;}   // Pwm ramp + 1 * 0.01second pure integrator    if (consigne    if ( Rcy>254)  {Rcy=254;}           // Limitation of duty cycle    analogWrite(PWM10,Rcy);   // Frequency 32kHz timer2}         } if (Imoteur>4000)  { Rcy=Rcy-5;              // No current filtering, to be faster                     if ( Rcy<6)  {Rcy=5;}       // Rcy is not signed, nor the PWM therefore Rcy minimum must not be less than 6                   analogWrite(PWM10,Rcy);   // Frequency 32kHz timer2}                        } 5. Closed Loop Program, Limited Current Control with Acceleration Handle An acceleration handle provides a 0.8V voltage when not operated and a 4.5V voltage when the handle is fully engaged. Instead of using pushbuttons to increase or decrease the speed setpoint, an acceleration handle will be used Code: [Select] Upoignee=analogRead(A3); // The relation in Upoign and the setpoint which corresponds to the duty cycle corresponds to if (Upoignee>100) { consigne=(Upoignee/2);     //0=a*200+b    et 255=a*800+b                      consigne= consigne-100;                   }                            else { consigne=0;   }               if (Upoignee<100) { consigne=0;  }     // redundancy     6. Temperature and safety program of the motor with the current measurement The outdoor temperature measurement can be easily performed by the LM35 component which charges 0.01V by degrees Celsius Code: [Select] temperature=analogRead(A2); //lm35 0.01V/°C temperature=temperature/2;       // Temperature coefficient lcd.setCursor(5,2); lcd.print("      "); lcd.setCursor(5,2); lcd.print(temperature);   // Display in ° C lcd.setCursor(9,2);      // Erasing secu display lcd.print("     ");   if (temperature>80 ) {lcd.setCursor(9,2);         // If motor external temperature is above 80 ° C                      lcd.print("secuT");                       Rcy=0;} In addition, thermal safety by measuring the motor current will be added. If the limitation current is greater than 10s then the motor will no longer be powered for 30s. A "secu" display will appear on the LCD display. This safety makes it possible to cut the motor on slope too high and when blocking the engine but it would be necessary to add the measurement of the speed in the latter case Code: [Select] if (timesecurite>=10000 ) {flagarret=1;      // If limitation current for a current of more than 10s                               timerepos=0;                               consigne=0;                               Rcy=0;                                 timesecurite=0;}       //   Then stop engine during a downtime    if (flagarret==1 ) {lcd.setCursor(9,2);         // If limiting current for a current of more than 20s                      lcd.print("secU");  }     //   Then stopping the motor for a stop time and display                                                     if (timerepos>=30000 &&  flagarret==1) {flagarret=0;                                           lcd.setCursor(9,2);      // After a rest time here of 30s                                            lcd.print("       ");   }   The display can be observed if the temperature is above 80 ° C https://i58.servimg.com/u/f58/17/56/35/17/a017.jpg Thermal safety by measuring the motor current (digital thermal relay) which allows to know the image of the internal temperature of the engine would be ideal. But for this, it is necessary to know well the thermal modeling of the motor. 7. Measurement of the energy capacity of the battery The energy capacity of a battery is in A.H, we will display the value in mA.H to have a high accuracy. The capacity will be in A.Second in the following equation. So to have in mA.H, it will be divided by capacity by3600. Capacity (A.s) n = I * Te + Cn-1 with Te = 0.01s and I multiplied by 10 So in the interrupt routine Code: [Select] capacity=ImoteurF+capacity ; And in the display Code: [Select] lcd.setCursor(0,3); // Display of energy capacity lcd.print("C mA.h="); capacity1=capacity/(18000);   //18000=3600*5  5=> Current measurement coefficient lcd.print(capacity1); To check a current of 10A with an adjustable resistor and after 30s, the capacity must be 83mA.H 8. Power and modeling with SIMULINK Modeling helps to understand the vehicle and its control. In addition, it is possible to compile the control part directly into the Arduino program from simulation under Simulink. But it will not be possible to simulate the instrumentation with the LCD display. In the following figure, we can observe the simulation of the programming of the chopper with the current limitation with Simulink. In the following figure, the green box shows the duty cycle control to vary the speed and the red border the current limitation. The controller of the control is here a simple integrator but it is possible to carry out a multitude of control. https://i58.servimg.com/u/f58/17/56/35/17/azub_c15.jpg In the previous figure, it can be observed that the current is well limited to 25A from 2s to 9.5s. Then, the current reaches 10.8A under established speed regime at 22.5km / h. The dynamics are similar to the tests carried out. With a slope of 5%, the cyclic ratio reaches only 100% as can be seen in the following figure. The speed will reach painfully 19km / h with a current of 24A and a motor power of 580W. See article: Study of electric scooters 100W and 500W (Arduino), 9. First conclusion It is easy to control a 500W DC motor with an Arduino and some components So repair many scooters that are in DC motors. But it takes some knowledge (automatic, engine) to know how to properly manage the engine and limit its current so as not to damage it The display of the speed, the distance, the operating time to know the Watt.km / km can also be realized with a menu 2. The .ino program as an attached file, But it is not possible to put an attached file in ISIS electronic labcenter? What is this forum? It would be desirable that the compiler could generate the.cof to debug in Isis and test the program line by line .... Arduino still has to make a lot of effort to be on the same level as other microcontrollers 10. speed measurement (tachometer) Velocity measurement is carried out using a hall effect sensor SS495 or A1324 which counts each revolution of the wheel. It is enough to enter the perimeter of the wheel of the scooter (130mm of radius therefore 0.816m in the case To have the speed, it is enough just to divide the number of turn of wheel on an arbitrary time of 1s to have a minimum speed of 0.81m / s therefore of 2.93 km / h. In addition, an average filter with 3 values will be used to display the speed. At 25km / h, there will be 8.5 laps. To count the turns, an external interrupt routine will be used on input INT0 21 of the mega card. http://www.locoduino.org/spip.php?article64 To simulate the speed, a pulse on input 21 will be used with a duty cycle of 10%. https://i58.servimg.com/u/f58/17/56/35/17/a018.jpg Code: [Select] void INT0b21() {   Tspeed++;   // External interruption to count the number of turns } // In the set up declare the interrupt routine when the 5V edge of the magnet detection is done   attachInterrupt(digitalPinToInterrupt(21), INT0b21, RISING );  // External interruption // In loop if (temps09>=5)  {        // 1 second loop lcd.setCursor(13,2);      // Erasing speed lcd.print("kph     "); lcd.setCursor(16,2); speed1=Tspeed*2937;      //1tour*816*3.6/1s=2.937km/h speed2=speed1;           //Tspeed (rate/seconde) speed3=speed2; speedF=(speed1+speed2+speed3)/3000;   // To put in kph lcd.print(speedF,1);    // Display to the nearest tenth Tspeed=0;   // Reset counter temps09=0;  //reset time } To improve the accuracy of the velocity measurement, it is possible that the sampling time of the velocity measurement is dependent on the velocity. For example: For speeds less than 10km / h sample at 1second, but above 10km / h sample at 2 seconds. 11. Distance measurement for autonomy The distance corresponds to the total number of turns of the wheel multiplied by the perimeter of the wheel. So do not set the number of turns to 0 for each sample. On the other hand, the reset of the distance will be done when pressing the reset of the Arduino Mega. The distance display will be displayed to the nearest second. At 32km / h, it will take 2 minutes to do 1km as can be seen in the following figure: https://i58.servimg.com/u/f58/17/56/35/17/a019.jpg Code: [Select] void INT0b21() {   Tspeed++;   // External interruption to count speed   nbrRate++; } lcd.setCursor(13,4);      lcd.print("km      ");  // distance=(nbrRate*816)/1000;  //distance m distance=distance/1000;  //distance km lcd.setCursor(15,4);      lcd.print(distance,1);  You can observe the electrical installation with the chopper, the arduino, and the display when the program is set up https://i58.servimg.com/u/f58/17/56/35/17/dsc_0613.jpg 12. Synthesis The RAM space is used only at 4% and ROM space at 3%, for an Arduino mega. So we could take an arduino a little smaller. But, there are 8 Lipo cells to make the 24V power supply to power the engine via the chopper. Therefore, the voltage measurement of each element will be on the Arduino with a JST connector. This measurement makes it possible to know if a cell with an internal resistance which begins to pose a problem and to know if the balancing of each cell has indeed been carried out. It is possible to switch to 36V with 12 cells also with the arduino mega without using an external shield that multiplex 24 analog inputs on input A0 It is possible to send all data to a smartphone via Bluetooth HC06 via pins 20, 21, RX1 and TX1. But the application under android realized under JAVA Studio can not be shared on this forum. This part will not be explained. After having made the instrumentation of this scooter, a study should be carried out on the precision of the measurements, it is possible to read "Instrumentation of a low-power electrical motor vehicle" eco marathon "type Revue 3EI N ° 81, July 2015 http://www.fichier-pdf.fr/2015/09/07/instrumentation-vehicule-faible-consommation-eco-marathon/

Topic by Iutgeiisoissons