Remember the Loving Little Braitenberg Vehicle I wrote about last month? Well, it seems that it has an even smaller little brother that only weighs 17 grams. And besides being in love with light, this itty-bitty Braitenberg vehicle can also show a different behaviour – being ‘aggressive’ towards it.
The vehicle has its own custom PCB and has the ATtiny25V from Atmel as its brain. Motion is acquired using two pager motors that run in one direction only, so the vehicle can only move forward. The parts list also include the MPC1700 3.3V voltage regulator, 2 light dependant resistors (LDRs), 2 2N3904 transistors, two 1N4148 diodes, rubber tubes that are used as wheels and a few resistors and capacitors. The whole device is powered by a small Lithium-polymer 3.7 V with 100mAh battery.
The Braitenberg vehicle is controlled using two inputs provided by the light sensors and PWM signal. The microcontroller was programmed removing the resistors, a rather unorthodox method, but it seems to be working. The vehicle being so small and its wheels even smaller, it should be tested on a clean surface. Also, if the surface diffuses the light you may experience some problems because the light sensors might be tricked by this.
All in all, another little Braitenberg Vehicle that is… well, adorable :). Schematics and demo video available in the link below.
Miniature Braitenberg Vehicle: [Link] – [via]
Here is a good project for those who want to start with robotics. Fairly simple and if you are using a breadboard there is no soldering involved. It is a vehicle that follows a light source using two LDRs, two servo motors, two wheels and an Arduino as its brain. The two LDRs are placed one on the left and one on the right side of the vehicle and each one controls the motor from the opposite side.
Although this project can be done using discrete components alone, using an Arduino allows you to further develop the project. Light is detected by the two LDRs. Each LDR is connected in series with a resistor between Vcc and ground forming a voltage divider. The joint point between the LDR and the resistor is connected to one of the Arduino’s analog inputs.
You will need to play a little bit with the values of the resistor so that you get the right sensitivity for light detection. A variable resistor could be very handy. The motors who spin the wheels are two hacked servo motors. Since servo motors don’t spin 360 degrees there is a way explained in the project to transform them into gear motors.
Servo motors are however pretty easy to control with the microcontroller. You have a center value which will make the motor stand still and if you add or subtract from that value it will make it go forward or reverse. You will need to run a few tests to determine these values and to adjust the light sensors.
Braitenberg robot with Arduino: [Link]