Hello

I am trying to build a segway, I know how I am going to make it, but I have been struggling to get the motorcontroller to work for days now.

I attached an accelerometer and a motorcontroller to an arduino uno. When I tilt the accelerometer 2 indicatorlights on the motorcontroller change, so this signal must be right. But when I measure the voltage at the motor output I get only 10-60 mV.

I tried using more and using less Volt (5-15 V) on the m.c. board itself. (I attached it to an old model train transformator)

Please Help

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The hardware that went into this Arduino gaming console is just fine. But the coding that produced this game called Twisted SNAKE is beyond compare. [Rodot] has programmed several games for the hardware, which uses an Arduino, 160×168 TFT screen, a 3 axis accelerometer, and two input buttons. If you’re interested, there is a forum thread in which he talks a bit more about the hardware design. But you’re not going to want to pass up either of the two videos embedded after the break.

The first clip shows off a bouncing-ball platforming game. The accelerometer moves the ball back and forth, and the top scrolling level brings more ledges into play. This in itself is a great game. But the Twisted SNAKE game shown off in the second video makes our own ARM-based Snake game look like a 3-year-old programmed it. [Rodot] filled up all of the program memory of the ATmega328 chip to  make this happen. There’s a menu system which allows for color themes and difficulty selection. The game play itself lets the snake travel anywhere it wishes with the tail following behind in graceful curves. Wow!

One of the people that I asked to look over the course notes and give me suggestions suggested another lab that would likely appeal to bioengineers:

another cheap experiment, accelerometers from Sparkfun to measure gait patterns or detect falls.  If really ambitious, you can teach chaos theory here with analyzing chaos levels in gait patterns—they are different for men and women.

I’ve used accelerometers before, both the analog output ADXL335 and the I²C MQA8452Q. The ADXL335 breakout board was from Adafruit Industries, the MQA8452Q from Sparkfun.  Although I personally prefer the I²C interface, since it takes up only 2 Arduino pins, programming is outside the scope of this class.

This lab sounds like fun, and it would be good for the bioengineers to think of accelerometers as cheap sensors that are easily used, rather than as magic that comes in cell phones, I’m not sure how we would get a circuits lab out of this. Even the analog-output accelerometer just needs to have its XYZ pins connected to analog inputs on the Arduino.  Anything interesting you do with the accelerometer is in either the mechanical mounting or in the software analyzing the data, not in electronic circuits.

We have several constraints in selecting labs for this circuits course:

• Lab must teach something useful to the students.
• Lab must seem interesting (or at least useful) to bioengineering students.
• Lab must not be dangerous (either to students or to equipment).
• Lab must be doable in one 3-hour lab session (we can afford at most 2 labs that are 2-session labs).
• Lab cannot require students to be able to program computers.
• Lab cannot require knowledge of electronics beyond what is taught in the course.
• Lab should support the teaching of traditional linear circuits.
• Lab should involve student design and not just analysis of existing designs.

The accelerometer lab fails on two points: any design component would have to be software and there is no support for teaching linear circuits in the lab.  That’s too bad, because it is otherwise a cool lab idea.

The Hackaday staff isn’t in agreement on 3d printers. Some of us are very enthusiastic, some are indifferent, and some wonder what if they’re as widely useful as the hype makes them sound. But we think [Jason Dorweiler's] self balancing robot is as strong a case as any that 3d printing should be for everyone!

Don’t get us wrong. We love the robot project just for being a cool self-balancer. Seeing the thing stand on its own (video after the break) using an Arduino with accelerometer and gyroscope sensors is pure win. But whenever we see these we always think of all the mechanical fabrication that goes into it. But look at the thing. It’s just printed parts and some wooden dowels! How easy is that?

Sure, sure, you’ve got to have access to the printer, it needs to be well calibrated, and then you’ve got to make the designs to be printed out. But these hurdles are getting easier to overcome every day. After all, there’s no shortage of people to befriend who want nothing more than to show off their Makerbot/RepRap/etc.

ArduSat, which stands for “Arduino satellite”, is a recently kickstarted project that aims at developing an open platform usable to emulate space scientists:

Once launched, the ArduSat will be the first open platform allowing the general public to design and run their own space-based applications, games and experiments, steer the onboard cameras to take pictures on-demand, and even broadcast personalized messages back to Earth.

ArduSat will be equipped with several sensors (such as cameras, gyros, accelerometers, GPS and more) packed inside a small cube (the side will be approximately 10 cm long) that can be accessed through a set of Arduinos.

Once in orbit, the ArduSat will be accessible from the ground to flash the required firmware for the experiments and for getting back all the collected information. People interested in performing space experiments will have access to a ground replica of ArduSat explotable to test and debug their code before the actual deployment.

The project is very ambitious, and it is expected that such an open accessible space platform will have a considerable impact on how simple space experiments will be carried out in the forthcoming years, in the case of fundraising success.

You may find the Kickstarter page of the project here.

[Via: Hack A Day and Kickstarter]

Researchers from Centro de Automática y Robótica (Universidad Politécnica de Madrid) and from Brown University carried out a very deep research about the specific behavior of bat flight, whose ultimate goal is to replicate the capabilities of bat’s wings by means of an ad-hoc designed micro aerial vehicle (MAV).

From the home page of the project:

[...] this research is oriented towards the development of a biological inspired bat robot platform, that allows to reproduce the amazing maneuverability of these flying mammals. The highly maneuverability is achieved by reproducing the flapping and morphing capabilities of their wing-skeleton structure. This structure is composed by several joints and a membrane that generates the required lift forces to fly.

To mimmic the muscular system that moves the joints of the wing-bones, Shape Memory Alloys (SMA) NiTi wires are used as artificial-muscles. Several challenges in controlling this SMA-based actuation system are regarded in this research.

A lot of research work has already been carried out (see here for a list of publications) and a bat-like MAV prototype has been designed and implemented to both evaluate and validate the research outcomes. Among the other stuff, the core onboard electronic is made up of an arduino-based board, an IMU, a radio transceiver and a rechargeable LiPo battery.

More details on this project can be found here.

[Via: BaTboT project homepage]

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:

Using an Arduino board with a data logging shield that holds an SD card for storage, an accelerometer on the front fork and some method of recording wheel speed, it’s possible to collect data about your bike ride. Then, when at home, a Python script captures the data dump and graphs it.

Wdm006 also says:

I’m in the process of building an ABS and active suspension system for mountain bikes. The first task after initial modeling and design work was to gather a lot of data for more specific design.

Original post can be read here.

Via:[Hackaday]

If you want to see what kind of abuse you’re causing your body when out on those single-track rides this system is just the thing. It’s an Arduino data logger that [Wdm006] takes along on the rides with him. When he gets back home, a Python scripts captures the data dump and graphs it. It may sound like a neat trick, but he’s got something planned for that information.

The enclosure mounts to the stem of his bike. It houses an Arduino board with a data logging shield of his own design. That shield holds an SD card for storage, and breaks the other pins out as screw terminals. Right now there’s an accelerometer on the front fork, and some method of recording wheel speed. This is the research phase of an anti-lock brake system (ABS) he plans to build for mountain biking. No word on what hardware he’ll use for that, but we can’t wait to see how it comes out.