Questions tagged [pwm]
Pulse-width modulation (PWM) is varying the duty cycle of a rectangle wave, usually with a constant frequency.
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How to: implementation problem with Position control on a 3 Wheels robot (2 motorized) with velocity profile of trapezoid
I'm trying to apply position control in a wheeled robot, controlled by an arduino mega.
The robot has two wheels powered by two dc motors (1 motor for each wheel) and one castor wheel.
In order to ...
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H bridge duty cycle vs maximum voltage
I've just burnt out an L298n H bridge, not surprising, but I thought it'd be ok for low load testing. Apparently not.
I'm considering ordering these to replace them - Hilitand DC 5-12V Motor ...
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How to control a dc motor
I have 2 of these 12v motors and a 12v battery
http://www.enigmaindustries.com/Motors/Bosch_EV_Warrior.htm
I would like to know what the best solution for controlling this motor with an Arduino Uno ...
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Quadcopter force/torques duty cycle conversion
after having been determined my control loops for my quadcopter project, I'm going to determine the motor commands (PWM duty cycle) from the motor forces/torques. I was following the guidelines of ...
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Robotic arm simulation in MikroC
I am supposed to control a robotic arm with a servo motor. The angle of rotation of the servo motor depends on the voltage of a potentiometer.
A0 can read analog inputs and C2 can hold a PWM signal.
...
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How to handle motor stall zones in differential drive point-forward go to goal algorithm?
I am implementing the Go To Goal algorithm for a differential drive robot as described here and in this video. The issue I have is that there is a large dead zone in pwm values where the motors are ...
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Impact of using PID Output as a Change (Delta) vs Absolute
I am trying to control speed of a motor using PID. It seems like I have two approaches.
Using PID to calculate the absolute duty cycle value of the PWM
Using PID to calculate the change needed in the ...
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are mg996r servo failures common?
I am new to the small servo area.
I bought a eBay 6DOF Robotic Arm, and 12 mg996r servos to go with it.
Using an arduino and I2C PCA9685 16 X PWM board, with the example code from adafruit, I set up ...
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Feed-forward controller with lookup table
does anyone have experience in implementing a feed-forward controller for a hydraulic cylinder?
Often, when a hydraulic cylinder is controlled with PWM values, people (https://drive.google.com/file/d/...
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Controlling digital servos
Many websites say that analog servo motors work on 50Hz and digital servo motors work on 300Hz. My question is, does this difference apply only to the inner control loop of the servo or does the user ...
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What network protocol/control units are motor-based robots controlled with?
I know most vehicles are controlled via CAN (Controlled Area Network) protocol through an ECU (Electronic Control Unit) which send/receives data using this protocol and then sends/receives Amps/Volts ...
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What is the noise in this PWM signal?
I'm in the process of calibrating servos while constructing a new hobbyist robot arm. When testing the base rotation servo I noticed some unexpected noise in the PWM signal while the servo is in ...
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PID control brushed motors via PWM using Encoder Clicks at SetPoints/Measurements
I've read numerous posts (1 , 2, 3 ) about using PID to control motors. All examples I've seen deal with the control signal being in the same units as the measurement signal. For example, use PID to ...
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Quadcopter PID Algorithm
I'm trying to implement a PID control on my quadcopter using the Tiva C series microcontroller but I have trouble making the PID stabilize the system.
While I was testing the PID, I noticed slow or ...
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Encoder based speed control for Rover 5
I am trying to get precise control over the speed of rover 5 based robot. It has four PWM controlled motors and 4 Optical Quadrature Encoders. I am using 4-channel motor controller with rover 5 ...
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How to control the speed of servo?
I am using FPGA board and servo, I read that with PWM I can control where the servo will rotate. If the duty cycle in PWM is 1.5 ms it goes to the center, if it is 2 ms it goes to clockwise and if it ...
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Motor driver PWM frequency
What can happen to the motor driver if I give input PWM frequency more than the rated(capacity)?
I'm using Maxon motor with specifications:
Operating on 24V
Speed: 600 RPM
Nominal Torque: 21 Kg-cm
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Serial command receiving failure with Arduino and Adafruit shield from C# desktop application
For a long time I use Arduino Uno controller and Adafruit Servo Shield with 6.3V 1000 uF capacitor, powered with 6V 8Amp adapter to control 8 digital servo motors ...
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Relation between PWM frequency and torque
I am using Pololu G2 18v15 to drive a maxon motor. The motor is supposed to drive a load in a sinusoidal trajectory against gravity with maximum torque of 0.0634 NM with max speed of 5 rpm.
I am using ...
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Should I use an arduino to control my balancing robot's motors?
I'm building a 2-wheel balancing robot from old parts. DC motors from an old printer, wheels from a BBQ, bodywork from an old optical drive etc.
The brain of the robot is a Raspberry Pi 3. I'm using ...
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Pulse Position Modulation as used in RC controls
How are several channels multiplexed down to a single physical wire? If two channels are transmitting the same value in the same frame, wont there be an overlap of the pulses?
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how to normalize PWM if the value exceeds the maximum speed limit
I have implemented inverse kinematics for nonholonomic mobile wheeled robots, and the RPM range of the motor that I used is -50 to 50, while for PWM is from 1300 to 1700. But in certain cases, the RPM ...
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Raspberry Pi Robot Car won't drive straight, right wheel is faster [duplicate]
My Raspberry Pi car bot will not drive straight at all.
After examining and listening to the two motors, I noticed that the right wheel is a lot faster. I have matching wheels and the same code ...
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Will a change of motor driver improve motor performance?
I have this motor, from datasheet it works on the 6-12V range and has a no load current of 0.52A, and a stall current of 20A. I want to test the motor before buying an expensive motor driver.
I have ...
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BBC Micro bit PWM link to CC3D quad controller
I am trying to create the following set up as a project in education:
QAV250 quad with CC3D controller
2xBBC Micro:bits used as the receiver, giving out 50 Hz PWM signals to the CC3D controller - one ...
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What do the commutation waveforms look like for a brushless motor?
I have seen waveforms for driving a brushless motor.
I guess this is the waveform used for the simpler block commutation. But if I want to do sinusoidal waveforms, what does the PWM signal look like ...
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how to sync the timer in control system with ROS?
To simulate a system, a global timer will be set and all submodules will be synchronized with that timer to work together. such as PID controller, kalman filter, PWM module etc.
How do you sync the ...
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Why do my ESCs stop working?
I'm new to robotics and this is my first time building a quadcopter. I'm unable to work out why I keep losing ESCs.
Most recently in testing, I've managed to calibrate all 4 ESCs and accurately ...
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Arduino output SPWM using Matlab
I have Arduino and Matlab which has hardware support package for Arduino.
I want to create SPWM signal (sinusoidal pulse width modulation) to be the output of the Arduino board.
I could generate the ...
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Where I can learn algorithms or and find examples of code for controlling a rover? [closed]
I am a programmer by profession and new to Robotics. I have studied ECE, so know electronics, but not very familiar with mechanical aspects of robotics. I am working on a learning project with Dagu ...
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Alternative to BeagleBone Black for Node.js based remote control project?
I am working on a remote control project that involves using Node.js and Socket.io to transmit joystick data from a webpage to my BeagleBone Black.
However, I am somewhat disappointed with the ...
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Change PWM values according to encoder output
I have a motor with an encoder. When I set the speed of the motor it should change its speed so that encoder readings per second should fit an equation $y = ax^2 + bx + c$ where ...
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How can I increase the resolution of a PWM signal?
Say I have a motor and I want it to spin at exactly 2042.8878 revolutions per minute. Say I have a very precise sensor to detect the RPM of the motor to a resolution of 1/1000th of a revolution per ...
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How to use specific ESC,BLDC motor through Arduino Uno R3?
Attempt to clean up:
I'm trying to use this motor with this ESC and an Arduino Uno R3.
Typically, I used the PWM pins when I use the Arduino and an ESC, but I can't control the motor even if I use ...
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Drive motor voltage / other specifications of Roomba 650
I salvaged some parts off my dead Roomba 650, and I'm trying to use the drive motor assembly . I got the pinout of the connector but I don't know what voltage / PWM / other specifications are there ...
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Quadcopter Throttle and PID mixing to Motor Speed
I've been writing some quad copter software and I am not sure what the best way is to map the throttle and PID inputs to ESC power.
My throttle range is 0-1 and my PID outputs are 0-1. My ESC's have ...
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PWM PID control for small 2 watts brushed DC motor
It is "good enough" for PID output directly controls, without further modelling, the PWM duty cycle?
Logic behind the question is,
In case of pure resistance heater, PWM duty cycle percentage ...
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Motors response different with high-frequency PWM
We are making a junior soccer robot and we just got our brilliant motors from Maxon.
Setting the PWM timer to low-frequencies (around 39kHz or 156 kHz ) the robot acts as expected. But this produces ...
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Outputting a precise voltage in millivolts on Arduino Mega
So I need to output a varying voltage off an Arduino Mega in a range of 17 to 32 millivolts, which I've attempted to do by sending a PWM signal off the board into a low-pass filter which steps down ...
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Reducing motor speed without jamming up
So I built three little bots so far.
One with a raspberry-pi, (6V motors), one with an arduino (12V motors), and another with an arduino but a hacked remote car (7ish, volt motors):
The problem I ...
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Limits of PWM, Timers and Interrupts?
I have a robot with two wheels/motors and each has a quadrature encoder for odometry. Using the wheel/motor/encoder combo from Pololu, I get 48 transition changes per rotation and my motors give me a ...
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Dropping PWM on Ardrone Parrot 2.0
I am having some issues with the ARDrone Parrot 2.0 and hope someone else may be running into the same thing.
While hovering, the drone is (seemingly) randomly losing altitude then recovering . It is ...
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How do I interface a TLC5947 with small motors?
This is a follow-up to this question: Prototyping a device with 25-100 small DC 3.0V motors, is Arduino a good fit?
I've decided based on the answer that sending the control signals through multiple ...
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How do I model a robot?
The answers I received to the question on training a line following robot using reinforcement learning techniques, got me to think on how to train a robot. I believe there are essentially two ways -
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