The system supporting the work of kart track

This project was designed for the kart track in order to automate the detection system and measuring the time to end of the ride. The assumption was that nine gokarts can move on the track at once, so there was a need to countdown three times independently.
Functions:

• modular construction and ability to add new modules
• time measurement regardless for each vehicle
• signaling the end of ride by red light
• the ability to set any time for each vehicle separately
• group starts – the simultaneous release of a group of vehicles and the group set of times
• clock
• deleting times
• remote read of the remaining time on an extra panel

The system consists of four modules, two of which are identical. Central module is equipped with a keyboard, LCD display, RTC and buzzer. Table module consists of 27 relays which control the LEDs in three colours. Control box module has 9 LCD displays, four boxes each. The displays are controlled in the following way: all 36 cathodes are connected in four groups switched ULN2003 and the individual anodes are controlled from registers 4094. The modules are linked together using computer twisted pair and RS485 bus, additionally the remaining cables distribute power to the system's components.
Boards were made by thermal transfer method on one-sided laminate. Supply is an old AT power supply and a separate transformer 24V for the relays. The keyboard was made of the buttons of PC keyboard.



Link to original thread (useful attachment) – Układ wspomagający pracę toru kartingowego