Vermes
Advanced Member level 4
It is a linefollower of own construction. Elements which were used in this construction are typical for that kind of robots.
Electronics:
The main element of the robot is microcontroller Atmega8 clocked by an external oscillator 8MHz. Sensors CNY70 are responsible for detecting the lines to follow. Those sensors are connected with the comparators LM339. Engines are controlled by PWM signal via a two-channel bridge L298. There are also 7 LEDs on the PCB which indicate the state of sensors. It is also equipped with gates NOT and NAND. Everything is powered by a LiPol accumulator (11,1V 800mAh, which is enough for 10 minutes of continuous operation at medium fulfillment of PWM). Voltage is stabilized by LM7805 and filtered by a few capacitors.
Mechanics:
The construction of robot is based on two-sided board made in thermal transfer method. There are two wheels in the rear, driven by microengines Pololu (30:1). On the front there is a ball caster 3/8 inch. Heat sink made of a piece of aluminum is used for removing the heat from the bridge and stabilizer.
Program:
Program was written in C. Socket placed next to the microcontroller is used for programming.
Control:
The robot is controlled using a standard program. It checks the sensors all the time and determines the corresponding PWM values.
Pictures:
Link to original thread (useful attachment and video)– Nimbus2000 Linefollower