Every so often you can find yourself unable to take a picture, because human reflexes can’t always handle the timing required in some circumstances. From wildlife photos of animals or lightning to various fast moving objects like bullets or even splashes or balloons popping, one can encounter many situations where hand-eye coordination or shooting skills just aren’t enough to get the job done. And here is where something like the Camera Axe comes into play.
This is an open source project, both hardware and software, that controls a camera or a flash, activating it at just the right time. The brain of the device is the ATmega328 microcontroller with Arduino Bootloader. The Camera Axe possesses a Flash Trigger to activate the flash with, a Camera Trigger for the camera itself, a Sound Sensor and a Light Sensor. The sound sensor is built using an electret microphone and its sensitivity can be adjusted with the potentiometer on the PCB. The light sensor is made with a photo transistor that detects both visible light and IR. The Camera Axe also has a RF receiver so it can be triggered remotely from about 200ft.
I have a lot of respect for open source stuff and this project makes no exception. You can find a detailed component list, schematics, pictures of the PCB, the enclosure and more pictures taken using the Camera Axe, as well as code and information about getting the board in the link below. The part list has detailed pricing for every component used, from voltage regulator and microcontroller to bolts and nuts and the whole thing costs about 120 dollars for a single Camera Axe, which is really cheap for what it can do.
A very interesting, fun, useful and detailed project, the Open Source Camera Axe is another tool for the photography enthusiast that is worth every penny. A demo video is also available in the link.
Open Source Camera Axe: [Link] – [via]
Open Source Camera Axe
As the modern day motor vehicles grow in complexity, the need for measuring various locomotion parameters is something that all manufacturers approach, regardless of the purpose, size or price of the vehicle. Motorcycles make no exception, especially with the need for speed of most bike enthusiasts.
A project for all motorcycle-loving geeks out there, the Arduino Control Panel for Motorcycles is still in the prototype phase, but it seems to be working flawlessly. It currently has a speedometer and a tachometer which are very accurate and also a gear indicator . It uses a standard Arduino, a small LCD and Bluetooth and it is powered by the motorcycle battery.
The device is connected to the electrical system of the bike, receiving pulses from the tachometer circuit and using a reed switch for wheel rotation. It calculates the wheel speed in RPM and divides it into most recent engine RPM, obtaining a unique ratio for each gear. This is done by counting how many times the engine turns while the wheel turns once and the answer is somewhere between 4 and 12 for 5th gear and 1st gear, respectively. An interesting aspect of the coding is the interrupt handling, which is done by logging every 10th one.
As with all prototypes, this is not the final version of the project. The designer plans to make the device smaller and to incorporate it into the tank console and also to enhance it with more functions, like wind resistance. Not sure about the usefulness of the whole thing, as all bike producers install similar equipment, especially on newer models. Still, an interesting project that could be further developed.
Arduino Control Panel for Motorcycles: [Link] – [Via]
The Braitenberg vehicles, an idea developed by cyberneticist Valentino Braitenberg, are autonomous vehicles that move around using wheels and light sensors connected to them. Motion is acquired using only the interaction between the vehicle and its environment, without information processing or internal memory of any kind. Still, the Braitenberg vehicles appear to have intelligent behavior because they react to their surroundings, changing speed or direction accordingly. For that, they are regarded as the simplest form of behavior based artificial intelligence.
These vehicles can exhibit various types of behavior, similar to “aggression” or even “love”. Yes, that’s right, this is a tiny car that loves light. It follows the light source, turning after it and stopping when the light is powerful enough. The motors run at full speed if it’s dark and when light is detected by one of the sensors, the motor on that side is slowed down, so the vehicle changes its direction towards the light. When the light is bright enough, both motors are stopped and the vehicle remains still. If the light source is moved, the vehicle will start moving towards it as soon as the sensors detect the change of light intensity.
As most of these vehicles, this light-loving car is rather simple in design and hardware, using an Arduino Mini Pro on a 170 tie points Mini Breadboard, both from Sparkfun. For locomotion, the vehicle uses 2 HXT500 mini servos working at 3.7V from Hobbycity and 2 GM10 wheels from Solarbotics. Seeing is provided by 2 Light Dependant Resistors. Finally, the vehicle is powered by a 3.7V LiPo cell with 800 mAh from Sparkfun, which is enough for the Arduino Mini Pro working at 3.3V.
This has got to be one of the cutest cars I’ve seen, you can check out the demonstration video in the link.
Loving Little Braitenberg Vehicle: [Link]
Earlier I presented a project on how to measure temperature with a LM35 and an Atmega8 microcontroller and display it on LCD. In the current project an Arduino board is used and the temperature reading is sent to a PC. A software is written for PC to display the data received on USB from the Arduino. It shows temperature value both in Celsius and Fahrenheit, numerical and as a bar-graph and a histogram with 100 data points.
The sensor is connected to one of the analog inputs of the Arduino. The code for microcontroller is very simple since all it does is convert the analog output of the sensor to digital and send it to PC and it does that every second.
The PC software is written in Processing, all code is available in the link.
Arduino Thermometer: [Link]
Keyless entry has been used for quite some time in automotive industry by most car manufacturers even though such a system may not be in their standard package. The owner receives a card or a small device, much like a remote control, and just by approaching the car, no buttons pushed, the car senses the master and opens its doors.
In this project is presented a method to build your own keyless entry system. Your RFID will be a Nike footpod which will send the secret code to its iPod receiver. This receiver communicates with an Arduino Pro Mini through an iPod Serial Board. The Arduino listens for the right code from the RFID and gives lock/unlock commands.
You can give these commands to your car’s fob or adapt it to the internal wiring of the door’s lock/unlock mechanism. This can be pretty tricky for there are several systems used for door locking. In some European cars like Volkswagen, Seat, Skoda the command for lock/unlock is given on a single wire. For example if on this wire the computer sees a firm ground then it will unlock if it sees a resistance to ground then it will lock or the other way around. In these case you will need to use diodes or relays.
Asian cars usually have two wires, one for lock one for unlock. You will need negative or ground to control these wires. Things complicate however with the more expensive cars as they use vacuum systems or sophisticated computers inside the door. Usually these cars when equipped with a factory keyless entry system have a sensor behind the door handle that must be triggered in order for the doors to unlock, even if the car senses its owner nearby.
Powering our keyless system requires that you find a permanent 12V supply in your car. Look at fuse box, under the driver’s kick panel behind the steering wheel for thick wires and use a multimeter to measure the voltage. Do not trust thin wires as their 12V can disappear after car’s computer falls asleep. Usually that happens between 15 to 30 minutes after locking the car. Be careful with this because serious damage can be caused.
Other difficulty you can experience, as the project’s author did, is the car’s door locking settings. If you unlock the door but do not open it the car might lock it again after a short period of time. You can change these settings from the car’s computer with a diagnosis tool.
RFID Keyless Entry: [Link]
