Recent Updates
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Updated on: Aug 02, 2013
Measuring rotation of a wheel or other shaft using encoders
Encoders are devices for measuring the rotation of a spinning shaft. Encoders are typically used to measure the distance a wheel has turned which can be translated into the distance the robot has traveled. The distance traveled over a measured period of time represents the speed of the robot, and is another common use for encoders. Encoders can also directly measure the rate of rotation by determining the time between pulses. This article covers the use of quadrature encoders (defined below) For non-quadrature incremental encoders, see the article on counters. For absolute encoders the appropriate article will depend on the input type (most commonly analog, I2C or SPI).
Manual WPILib programming -
Updated on: Aug 02, 2013
Using Counters
Counter objects are extremely flexible elements that can count input from either a digital input signal or an analog trigger.
Manual WPILib programming -
Updated on: Jul 31, 2013
Analog inputs
The NI 9201 Analog to Digital module has a number of features not available on simpler controllers. It will automatically sample the analog channels in a round robin fashion, providing a combined sample rate of 500 ks/s (500,000 samples / second). These channels can be optionally oversampled and averaged to provide the value that is used by the program. There are raw integer and floating point voltage outputs available in addition to the averaged values. The diagram below outlines this process.
Manual WPILib programming -
Updated on: Jul 30, 2013
Measuring robot distance to a surface using Ultrasonic sensors
Ultrasonic sensors are a common way to find the distance from a robot to the nearest surface
Manual WPILib programming -
Updated on: Jul 30, 2013
Determine robot orientation with a compass
A compass uses the earth’s magnetic field to determine the heading of the robot.
Manual WPILib programming -
Updated on: Jul 30, 2013
Accelerometers - measuring acceleration and tilt
Accelerometers measure acceleration in one or more axis. One typical usage is to measure robot acceleration. Another common usage is to measure robot tilt, in this case it measures the acceleration due to gravity.
Manual WPILib programming -
Updated on: Jul 30, 2013
WPILib Sensor Overview
The WPI Robotics Library supports the sensors that are supplied in the FRC kit of parts, as well as many commonly used sensors available to FIRST teams through industrial and hobby robotics suppliers.
Manual WPILib programming -
Updated on: Jul 30, 2013
Choosing a Base Class
The base class is the framework that the robot code is constructed on top of. WPILib offers two different base classes, as well as a third option which is not technically a separate base class.
Manual WPILib programming -
Updated on: Jul 23, 2013
Your Second Program and beyond
By now you've learned how to code and deploy your first Java program. This article highlights additional resources as you look to add features and move beyond the basics presented so far.
Manual Getting started with Java -
Updated on: Jul 23, 2013
Your Second Program and beyond
By now you've learned how to code and deploy your first C++ program. This article highlights additional resources as you look to add features and move beyond the basics presented so far.
Manual Getting started with C++