Here’s proof that you can build cool stuff with simple tools. This self-balancing unicycle uses an Arduino and a five degree of freedom IMU from Sparkfun to keep the rider upright. Well, it’ll keep you upright as long as you have good side-to-side balance. But that’s true of any unicycle, right?

The Raptor was built by [Nick Thatcker] who is no stranger to self-balancing transportation. A few years back he built a Segway clone and the same type of geared motor used in that project also went into this one. I connects to the wheel with a chain, allowing him to keep the motor hidden in the saddle. He gets between 90 and 120 minutes of used on one charge with a top speed of 10 MPH. The motor could move you along faster but he has limited this in firmware to ensure it has enough power to ‘catch up’ if you lean too far forward.

Don’t miss the demo after the break. If you like this unicycle there are several others worth looking at.

[Willy Wampa] is showing off his self-balancing robot. What strikes us about the build is how well tuned his feedback loop seems to be. In the video after the break you will see that there is absolutely no visible oscillation used to keep its balance.

The parts used are quite easy to obtain. The acrylic mounting plates are his wife’s design and were custom cut through the Pololu service. They were also the source of the gear motors. He’s using a SparkFun IMU with an Arduino and a motor shield. He first posted about the build about a month ago, but the new revision switches to a Pololu motor driver shield which he says works much better, and adds control via a wireless Wii Nunchuck.

The PID loop which gives it that remarkably solid upright stance is from a library written by [Brett Beauregard]. Once again the concept of open source lets us build great things by standing on the shoulders of others.

[via Reddit]

I'm building a balancing robot using Arduino Uno & a MPU6050 IMU.

I've never programed anything before so naturally I'm struggling a bit.

I've got some code that calculates an angle from the accelerometer reading & I need to do the same for the gyro reading to feed into a complimentary filter. However it's not working & I haven't figured out why. (I've used the lirbray built by Jeff Rowberg and some of his code too).

Please have a look at the code attached & see if you can help me out a little.

read more

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I'm building a balancing robot using Arduino Uno & a MPU6050 IMU.

I've never programed anything before so naturally I'm struggling a bit.

I've got some code that calculates an angle from the accelerometer reading & I need to do the same for the gyro reading to feed into a complimentary filter. However it's not working & I haven't figured out why. (I've used the lirbray built by Jeff Rowberg and some of his code too).

Please have a look at the code attached & see if you can help me out a little. 

read more

At this point we’re beginning to think that building a self-balancing robot is one of the rights of passage alongside blinking some LEDs and writing Hello World on an LCD screen. We’re not saying it’s easy to pull off a build like this one. But the project makes you learn a lot about a wide range of topics, and really pushes your skills to the next level. This latest offering comes from [Sebastian Nilsson]. He used three different microcontrollers to get the two-wheeler to stand on its own.

He used our favorite quick-fabrication materials of threaded rod and acrylic. The body is much taller than what we’re used to seeing and to help guard against the inevitable fall he used some foam packing material to protect the top level. Three different Arduino boards are working together. One monitors the speed and direction of each wheel. Another monitors the IMU board for position and motion feedback, and the final board combines data from the others and takes care of the balancing. Two PID algorithms provide predictive correction, first by analyzing the wheel motion, then feeding that data into the second which uses the IMU feedback. It balances very well, and can even be jostled without falling. See for yourself in the clip after the break.

There are many Quadrotor Projects out there. But, they require a hobbyist to deal with the Frame Designing (Mechanical), a bit of Microcontroller knowledge as well as dealing with the Motor Control (Power Electronics). You may purchase a commercial Radio and a readymade Kit for flying. But, to Do-It-Yourself, is an achievement in itself.

Here is a picture of a Quadrotor designed by Shane Colton using Arduino Pro mini as its flying brain. Shane is a Ph.D Student at Massachusetts Institute of Technology. On being asked about the Project, he replied:

I heard about Arduino some time in 2007/2008 and have used it for a few projects since then. I built the quadrotor for fun / hobby (not related to research). I wanted to build my own (quadrotor) from scratch because I could integrate all the parts onto a single circuit board, and because I like designing the control system myself.

When he says he build the quad from scratch, he literally did it. Neither did he use any commercially available Radio Control, nor did he use any Electronic Speed Controllers (ESCs). Instead he went for creating his own Brushless DC Motor Controller, that too, on the same PCB which acts as the Quadrotor’s Frame.

He spent a lot of time researching about propellor balancing as well as vibrations in the PCB. Here is a video:

Now, that is called a hobby. In a detailed Instructable, he shows how you too can build a Quadrotor on a PCB. He has a project blog at http://scolton.blogspot.com with documentation on most of his projects.

Enjoy the ride:

Makers need to familiarize themselves with the core concepts and the theory involved in creating applications such as Motion Sensing and Face Tracking. As the technology is churning out new hardware day and night, DIYers need to work hard to keep up and always be in touch with the latest technology around them.

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For example, anyone working with Accelerometers/ Gyroscopes or Inertial Measurement Units needs to understand the theory of Vectors, Force, Gravity and be able to work out complex mathematical problems. They may easily get an Arduino Board and an Accelerometer Breakout or an IMU Board and use a library instead of writing their own code but to truly understand the theory behind it; how the device actually works, is not for the faint of heart.

One such problem is the Face Tracking Application. Unless you know the real theory behind how the Algorithm actually works, you can only wonder about that robot which follows its master. Greg Borenstein had an idea of creating a website dedicated to this issue. Makematics – Math for Makers.

In an introductory post, Greg writes:

” I hope to show that a normal programmer with no special academic training can grapple with these areas of research and find a way in to understanding them. And as I go I aim to create material that will help others do the same. If I can do it, there’s no reason you can’t.”

More and more people should step forward and create or compile a good amount of research data to help fellow makers and DIYers in solving complex mathematical problems.