The digital tachograph is a device used in road transport to monitor and control driving time. It consists of a Vehicle Unit (VU) that features a printer, display, and two slots for smart cards. The VU is connected to the vehicle’s gearbox through a secure sensor and serves as the central processing unit of the system. It can store data in its mass memory for up to 12 months, including information about driver activity, duty periods, and various types of events such as system faults, tampering attempts, and speeding incidents.
The VU also records data access by authorized personnel, such as law enforcement officers. The digital tachograph works by utilizing smart cards, which are issued to drivers, operators, calibration centres, and enforcement officers, each with their specific access rights. These cards enable the authorized parties to use and access the data stored in the VU.