If you are into Radio Control Models or robotics chances are that you have an old RC transmitter laying around. This article describes how to create a motion control module for your RC transmitter, that will allow you to control your model or robot by simply tilting the transmitter case. That's right not sticks!
Posts Tagged ‘accelerometer’
Quadcopter Prototype using Acc_Gyro and a PIC
For anyone following this site, here is what I've been up to lately – building a quadcopter based on the Acc_Gyro 5DOF IMU sensor and a 16bit PIC. Although it's still a work in progress I decided to start putting together an article placeholder and build it up as project evolves. It's going to be a long one !
The source code will be Open-Source and will be hosted here:
http://code.google.com/p/picquadcontroller/source/browse/#svn/trunk
As usual I like to start with a video demo, it's basically me controlling the tilt of the quad using a RC controller:
Play PC games the iPad style – Using a PIC with USB, accelerometer and optional Gyroscope
The iPad is finally out – one feature that might caught your attention is the built-in accelerometer and the ability to control a game by tilting the device. For more than a year I was working on a similar idea for the PC Notebook market based on my original motion gamepad project that would allow playing a game by tilting the laptop/netbook. Now that iPad is out I hope that the notebook/netbook manufactures will catch up by incorporating MEMS sensor into their devices. Here is the result of my prototype , it is a USB attached device, but ideally I think this should be embedded into the laptop.
Demo:
Exploring a digital I2C/SPI accelerometer (MMA7456L) with Bus Pirate
Bus Pirate is a great tool for exploring new chips using your PC , without the need to integrate the chip into a MCU project. Once I received my unit, i decided to put it to the test by exploring an accelerometer with I2C/SPI interface – the MMA7456L from Freescale. I am writing this in hope that it will help other people get started with BusPirate and I2C protocol in particular. I will only describe the I2C interface in this article but BusPirate is capable of so much more !
The setup of BusPirate was simple. Simply plug it to your USB port, install the FDTI driver (if necessary). After that it will appear as a virtual COM port on you computer. You then can use your terminal of choice to interact with it. Here is sample session in Termite (my choice of terminal software):
Arduino code for simplified Kalman filter. Using a 5DOF IMU (accelerometer and gyroscope combo)
This article introduces an implementation of a simplified filtering algorithm that was inspired by Kalman filter. The Arduino code is tested using a 5DOF IMU unit from GadgetGangster – Acc_Gyro . The theory behind this algorithm was first introduced in my Imu Guide article.
The Acc_Gyro is mounted on a regular proto-shield on top of an Arduino Duemilanove board.
A Guide To using IMU (Accelerometer and Gyroscope Devices) in Embedded Applications.
Introduction
This guide is intended to everyone interested in inertial MEMS (Micro-Electro-Mechanical Systems) sensors, in particular Accelerometers and Gyroscopes as well as combination IMU devices (Inertial Measurement Unit).
I'll try try to cover few basic but important topics in this article:
- what does an accelerometer measure
- what does a gyroscope (aka gyro) measure
- how to convert analog-to-digital (ADC) readings that you get from these sensor to physical units (those would be g for accelerometer, deg/s for gyroscope)
- how to combine accelerometer and gyroscope readings in order to obtain accurate information about the inclination of your device relative to the ground plane
Accelerometers reviewed and tested. Part 1: DE-ACCM2G (ADXL322), LIS244AL, Pololu MMA7260QT
In the process of developing my usb motion gamepad I got a chance to work with different accelerometers. In search of the perfect device I wish there was a place where I can go and compare them side by side. The problem is that different manufactures have different methods of testing the noise parameters so the only way to get it right is to have them tested by a third party. I will start by analyzing 3 accelerometers I have in my possession, and hope to review more as I get my hands on them.
The accelerometers I will test are:
1) Dimension Engineering DE-ACCM2G (this is the older model based on Analog Devices ADXL322 chip datasheet ). It is now being replaced by a different model DE-ACCM2G2 based on LIS244ALH chip from ST). This is a quality product that unlike other break-out boards has a built-in amplifier.
2) Second device is a bare-bone LIS244AL , a self-mounted using reverse mounting method (yes it still works ! 
).
3) Finally is one of the cheapest accelerometer break-out boards out there the Pololu MMA7260QT.
Recently I completed my Gamepad Configuration Utility and decided to put to use for something it was not necessarily built for. I connected 3 accelerometers (to precize their X axis output) to the analog ports of PIC18F4550 (one of my gamepad prototypes "The Brick").
New and Updated Motion USB Gamepad: wide accelerometer and gyroscope support, configuration utility software
I have received some feedback from my readers regarding my first usb gamepad project , so for the past few weeks I was working on a new imrpoved design. There are plenty of new improvements that I hope will address many of your requests.
