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Pololu NCP1402 Boost Regulator??? Answered

How exactly do I hook this up?  Where does ground go?  Where does the Vin and Vout go?  This is the circuit but we're replacing the 7805 w/ the boost regulator.  Thank you!!    The pic of the circuit isn't showing up - the circuit goes: Coil /w magnet connected to diode bridge to capacitor to 7805 connected to the cell phone charger.  We're replacing the 7805 with the NCP1402 - do you know where it goes?  Thank you!

Question by mckywer    |  last reply

Pololu pushbutton power switch module control issue

Hello all: I'm using the low-voltage version of the Pololu pushbutton power switch module to power up/down an Arduino Mini project.  You can see it here: It works great, with an exception; if someone presses the single Pololu power switch while the Arduino is ON, it powers it off again. This may be normally what you want, but it isn't in my case.  I'd like the circuit to act like this: 1- wait for button press 2- push button 3- Pololu applies power to Arduino 4- Arduino boots up, loops until 30 seconds has passed.  After 30 seconds, send POWER OFF signal to Pololu. 5- Pololu powers Arduino down. 6- goto 1 It works like that, BUT if someone presses the button again during that 30 seconds, the Pololu powers the unit off right away.  I'd like to somehow disallow that, electronically. Anyone have any ideas? Thanks, Jim

Topic by jimlips  

Pololu Robotics Black Friday Sale Starts Thursday!

Hello everyone! Pololu Robotics is excited to announce our biggest Black Friday sale yet, with huge discounts on some of our most popular products.  In all, you can get up to $25 off your entire order in addition to saving up to 60% on dozens of selected items, including the 3pi and m3pi robots, Wixel wireless modules, Maestro Servo Controllers, Simple Motor Controllers, sensors, chassis, actuators, and much more!  Stock up on parts for your next DIY project and save big! Our "door-buster" deal, limited to the first 50 customers, is once again our 3pi robot for $49.95, but this time a USB AVR programmer is included (a savings of $62 off the retail price). For details, visit Happy holidays!

Topic by Pololu Robotics  

Pololu Robotics and Electronics Black Friday/Cyber Monday Sale 2014

Hi, guys. It's that time of year again: Pololu Robotics and Electronics is having its biggest Black Friday/Cyber Monday sale yet, offering huge discounts on over 600 products, along with 11% to 15% off orders over $100!  Save big on robots, programmable controllers (including A-Stars, Arduinos, Raspberry Pis, and mbeds), sensors, motor drivers, power supplies, LEDs, actuators, wheels, breadboards, wires, and more.  The first doorbuster deals go live Wednesday, November 26, and the sale runs through Cyber Monday (December 1).  For more details, please see our Black Friday/Cyber Monday Sale page. We hope these special deals bring some extra holiday joy to all you makers out there! - Ben

Topic by Pololu Robotics  

Pololu Robotics Black Friday Sale starts Thursday!

Hello everyone! Pololu Robotics is excited to announce our biggest Black Friday sale yet, with huge discounts on some of our most popular products.  In all, you can get up to $30 off your entire order in addition to saving up to 60% on dozens of selected items, including robots, sensors, motor drivers and controllers, chassis, actuators, and much more!  Stock up on parts for your next electronics DIY project and save big! For all the details, including a list of all of the sale items, visit Happy holidays!

Topic by Pololu Robotics    |  last reply

IR Reflective Sensors for Arduino?? Answered

I just ordered a bunch of reflective sensors... Similar to the sparkfun one (I've not decided digital or analog yet)...I'd like to connect them all up similar to the Pololu Arrays...  I want to hook up like ~30 and read them individually... How do you differentiate so many inputs into the Arduino? Is there some similiar code to work from? cheers!

Question by hydronics    |  last reply

I have a problem in the programming of Arduino Uno,2 motors,Qik2s9v1 and Pololu IR Beacon Transceiver. Help please!

I'm trying to make a robot like Micromouse robot.  Do not know much about Arduino. I've been trying to program, but I could not. This is my problem; I searched the programming provided by the Arduino Wed, for each of the components that constitute my robot.  When I go to work with motors and qik2s9v1, not I get the connection and the programation, for this.  Because, when I enter the programming qik2s9v1 tells me 'NewSoftSerial' does not name a type, download the codes of NewSoftSerial and fallow the problem. Well, if anyone can help me with my problem, or if you know a program similar to the components that constitute my project. I would be very grateful.

Question by Jesma_1992    |  last reply

Code writting?

I'm trying to build a line follower robot and I don't know the first thing about writing code.  I like to play with electronics but have never attempted building anything that requiered programing so I thought I would start simple.  I have an Arduino Uno R3, Pololu QTR-8 (only using 6 of the sensors) and an Ardumoto Motor Shield based on L298 H-bridge logic (not even sure what that means) Are there examples of codes existing on how to connect three componetns together?  What do I need to do next in order to connect these three parts and imput a code so it will smothly follow back tape on a white surface?

Question by bowhunter616    |  last reply

Electronics for a diy 3d printer Answered

Hello, I would like to know if these parts will be suitable for building a 3d printer without modifying the code made for 3d printer. Yes, I see modifying the code as inevitable for making the 3d printer accurate. If there are any other parts beside a powers supply, a the hot end parts I would appreciate that.. Can I use this microcontroller?;=item2a44248a77 And these step sticks?;=item4177c19222 Thanks for any help.

Question by jbaker22    |  last reply

Leadscrew stops and starts?

I'm trying to make a cnc plotter similar to this: I have changed some things though: I'm using aluminum rod with washers super glued to the end, another washer, and two nuts instead of flange bearings (brushings) and two nuts, I'm using 3/8 rod, pololu steppers (#1209), and slightly different conduit clamps.  I'm using a wooden dowel with a half-inch hole, and aluminum and nylon spacers tapped and with a setscrew to act as a motor coupler.  The problem I'm having is that as the motors rotate, even continuously in one direction, the gantry stops and starts moving.  It moves 1/16th of an inch per rotation, as it should, but within each rotation it moves quickly, probably 5/6 of the way within the first 180 degrees, then moves just the remainder in the last 180.  The motors do not stall, miss steps, or change speed, but the gantry does.  There is almost no backlash, and little play.  Any ideas whats wrong?

Question by jduffy54    |  last reply

Can I use the same ground line for 2 different DC voltage out puts?

It seemed a bit pointless to me to use an inverter to get mains voltage just to use a transformer to step it back down again to charge a lap top. This in hind sight may be the cheaper option. So I decided to build a power supply from commercially available parts this step up dc to dc device seemed to fit he bill coupled with a replacement charging lead from My problem is this, the mains power supply from HP doesn't mention that the central pin is a different voltage to the inside of the plug, as the new cable had 3 wires a stuck a multi meter on the mains adapter to check the outer is indeed negative, and the inner contact 19.5v as shown on the power supply label the unmentioned central pin is at 14.1v . I don't have any worries about running 2 step up devices in parallel from the same 12v supply. I'm a little concerned about using the same ground line for 2 separate devices even though the mains unit does. It has occurred to me that there is probably a simple way to drop the 19.5v to 14.1v for the central pin but I don't know if they run at the same current and if my understanding of electronics was up to that I probably wouldn't need to be asking what I suspect is a fairly basic question. I am pretty adept at assembling and checking out puts of  things others have designed I just don't understand the design bit.

Question by Stan1y    |  last reply

How to Solve the Problem of Stepper motor only turning in one direction

I've finally had the time to start putting together the electronics package for a CNC machine, and already need to do some debugging. ;)I'm trying to get one stepper motor going with the v2.58 board, a RPi 3, Popolu DRV8825, and one of these stepper motors.I've used the Pololu FAQs to tell me how to hook up the stepper to the RPi CNC board. On my stepper motor A is black, C is green, B is red, and D is blue. I'm getting this from examining the documentation that came with the stepper motor, and I used an LED to verify which wires were connected to each other. I examined the traces on the underside of the board to tell me how things connected to the stepper driver through the screw terminals. The green connector should go to 2B, 1B, 1A, and 2A in that order if you're looking directly at them.I can get the stepper to turn in one direction, but not the other. It acts like it's trying to move by jerking around, but doesn't actually start turning. If I move it in the other direction there's some jerkiness at the beginning, but it'll start spinning, jerk a bit more near the end, and stop. I've put a short video of this on YouTube.I've tried using another stepper driver, and gotten the same results. I've tried various different wiring options, but all I've managed to do is change the direction of the issue. I've also tried moving everything over to the Y-axis, and gotten the same result. I'm convinced this is something to do with my stepper motor wiring, but I'm needing some help on figuring out the right way to do it.Any help?

Question by ganshangkou2    |  last reply

Help for realising a linefollower tankbot

Hello, I want to realize a linefollowing tank bot. I got this following parts: - Arduino Mega 2560 - Arduino MotorShield Rev03 - Pololu QTR-8RC Array - Pololu RP5 Tankchassis (6V DC Motors) Now all parts are together and the code must be completed. Therefore I found a really nice PID-based tutorial for linefollower: I create a program, but after calibrating the sensors, the bot doesn't drive on the line. It makes no sense were it drives. Most time it do 90° turns and so on. Do you find a better solution for my code? [code] #include #include   /////////////////////////// // define constants   // /////////////////////////// #define AUTO_CALIB  false      // Autokalibrierung aktivieren #define DEBUG_ENABLE   true               // false=keine Serial Ausgaben #define NUM_SENSORS    8                  // Anzahl der verwendeten Sensoren #define TIMEOUT        2500               // waits for 2500 microseconds for sensor outputs to go low #define EMITTER_PIN    QTR_NO_EMITTER_PIN         // Default: kein Emitterpin definiert #define MOTOR_SPEED    100               // PWM Signal 0-255 (Basismotorgeschwindigkeit) #define MOTOR_MAX_SPEED 255       // PWM Signal für Maximalgeschwindigkeit #define KP     0.2                    // KP-Wert für PID Regler #define KD     5                     // KD-Wert für PID Regler ( Beachte: Kp < Kd) #define SERVO_PIN1  11       // PWM Ausgang für Servo1 #define SERVO_PIN2  12       // PWM Ausgang für Servo2 #define CALIB_LED   13       // LED Ausgang für Kalibrierungsphase ////////////////////////// // define variables     // ////////////////////////// // Zuweisung der Sensoren 0-7 an die digitalen IO's 22-29 QTRSensorsRC qtrrc((unsigned char[]) {22, 23, 24, 25, 26, 27, 28, 29}, NUM_SENSORS, TIMEOUT, EMITTER_PIN); unsigned int sensorValues[NUM_SENSORS]; int MotorLeftSpeed=3;                  // PWM pin for speed control left int MotorRightSpeed=11;                // PWM pin for speed control right int MotorLeftDirection=12;            // digital pin for direction control left int MotorRightDirection=13;            // digital pin for direction control right int MotorLeftBrake=9;                  // digital pin for brake control left int MotorRightBrake=8;                 // digital pin for brake control right int lastError = 0; ///////////////////// // Initialisierung // ///////////////////// void setup() {     // Initialisierung verschiedner IOs   pinMode(CALIB_LED, OUTPUT);    // Definiert LED Ausgang für Kalibierungsphase       // Initialisierung linker Motor   pinMode(MotorLeftDirection, OUTPUT);      // Definiert Ausgang für den linken Motor   pinMode(MotorLeftBrake, OUTPUT);          // Definiert Bremse für den linken Motor   pinMode(MotorLeftSpeed, OUTPUT);   // Definiert Geschwindigkeitsausgang für linken Motor   // Initialisierung rechter Motor   pinMode(MotorRightDirection, OUTPUT);     // Definiert Ausgang für den rechten Motor   pinMode(MotorRightBrake, OUTPUT);         // Definiert Bremse für den rechten Motor     // Initialisierung Servo Motoren   servo1.attach(SERVO_PIN1);     // Zuweisung PWM PIN für Servo1   servo2.attach(SERVO_PIN2);     // Zuweisung PWM PIN für Servo2   if (DEBUG_ENABLE)   {    Serial.begin(9600);    Serial.print("Debug Modus aktiviert:\n");     }     delay(500);     digitalWrite(CALIB_LED, HIGH);    // turn on Arduino's LED to indicate we are in calibration mode   for (int i = 0; i < 400; i++)   // make the calibration take about 10 seconds   {     qtrrc.calibrate();           // reads all sensors 10 times at 2500 us per read (i.e. ~25 ms per call)   } delay(20);      // The 20 ms delay in the calibration code is intended to make the routine take a reasonable amount of time.     digitalWrite(CALIB_LED, LOW);     // turn off Arduino's LED to indicate we are through with calibration       if (DEBUG_ENABLE)    {    // print the calibration minimum values measured when emitters were on       for (int i = 0; i < NUM_SENSORS; i++)    {   Serial.print(qtrrc.calibratedMinimumOn[i]);   Serial.print(' ');    }    Serial.println();       // print the calibration maximum values measured when emitters were on    for (int i = 0; i < NUM_SENSORS; i++)    {   Serial.print(qtrrc.calibratedMaximumOn[i]);   Serial.print(' ');    }    Serial.println();    Serial.println();   }   delay(1000);   } /////////////////// // Main Program  // /////////////////// void loop() {   // read calibrated sensor values and obtain a measure of the line position from 0 to 5000 // To get raw sensor values, call: //; instead of unsigned int position = qtrrc.readLine(sensorValues); // Variable positon zeigt die genaue Position (0-7000) an   unsigned int position = qtrrc.readLine(sensorValues); // get calibrated readings along with the line position, refer to the QTR Sensors Arduino Library for more details on line position. int error = position - 3500;  // 3500 is the desired position   if (DEBUG_ENABLE)   {    // print the sensor values as numbers from 0 to 1000, where 0 means maximum reflectance and    // 1000 means minimum reflectance, followed by the line position    for (unsigned char i = 0; i < NUM_SENSORS; i++)    {     Serial.print(sensorValues[i]);     Serial.print('\t');    }    Serial.print(position);    // comment this line out if you are using raw values   } int motorSpeed = KP * error + KD * (error - lastError); lastError = error; int rightMotorSpeed = MOTOR_SPEED + motorSpeed; int leftMotorSpeed  = MOTOR_SPEED - motorSpeed;     if (rightMotorSpeed > MOTOR_MAX_SPEED ) rightMotorSpeed = MOTOR_MAX_SPEED;    // Verhindert dass die Maximalgeschwindigkeit überschritten wird if (leftMotorSpeed > MOTOR_MAX_SPEED ) leftMotorSpeed  = MOTOR_MAX_SPEED;    // Verhindert dass die Maximalgeschwindigkeit überschritten wird if (rightMotorSpeed < 0) rightMotorSpeed  = 0;          // Verhindert einen negativen Geschwindigkeitswert if (leftMotorSpeed < 0) leftMotorSpeed   = 0;          // Verhindert einen negativen Geschwindigkeitswert   {   // Ansteuerung der Motoren durch PID Berechnung   digitalWrite(MotorRightBrake, LOW);     // Motorbremse rechts deaktivieren   digitalWrite(MotorLeftBrake, LOW);     // Motorbremse links deaktivieren   digitalWrite(MotorRightDirection, HIGH);   // Motor rechts im Uhrzeigersinn  --> fährt vorwärts   digitalWrite(MotorLeftDirection, LOW);    // Motor links gegen den Uhrzeigersinn  --> fährt vorwärts   analogWrite(MotorRightSpeed, rightMotorSpeed);  // Motorgeschwindigkeit rechts in Abhängigkeit des PID Reglers   analogWrite(MotorLeftSpeed, leftMotorSpeed);  // Motorgeschwindigkeit links in Abhängigkeit des PID Reglers }           } [/code]

Topic by julianpe    |  last reply