The Toyota Prius, the first hybrid car to be tested by Euro NCAP, has achieved a maximum rating of five stars.
The Prius also scored highly in the new Child Protection Rating, setting a new high score for any vehicle with 43 points, achieved thanks to the standard provision of the triple-anchor CRS (Child Restraint System) ISOFIX system and Toyota’s intelligent child seat design.
The Prius’s safety kit includes eight airbags, a dual-stage seatbelt warning system and a knee protection panel. Even the fascia-mounted starting button plays a part, as it does away with the ignition key cylinder on the underside of the steering column, which can cause injuries to the driver’s legs in the event of a collision.
During development, huge numbers of computerised crash simulations were conducted to help develop a bodyshell which offers the best balance between low weight and crash protection.
Around 45 per cent of the Prius’s bodyshell is constructed from high-strength steel, and in key areas such as the B pillars, is combined with a hot-stamping manufacturing process that renders the metal 2.5 times stronger than conventional high-strength steel.
To confirm the data from the simulations, the Prius was subjected to a programme of 125 real crash tests, substantially more than are usually conducted in the development of a new model.
Impacts between different size and weight vehicles constitute the most common type of accident in Europe, so the Prius was crashed into the much larger Toyota Land Cruiser as part of the testing regime, with both vehicles moving at 50 km/h.
To cope with rear impacts, the body strength was increased, the seat back structure reinforced, and Toyota’s WIL (Whiplash Injury Lessening) seat design, that protects the passengers’ necks from whiplash effects, was also fitted. WIL seats were recognised by the German national motoring organisation ADAC as the best among 10 different whiplash protection systems.
Both the high-voltage electric circuit and the fuel tank enjoy maximum protection in an impact. The hybrid battery is mounted over the rear axle – the safest place in the event of a crash – and the Circuit Break Sensor instantly disconnects the High-Voltage Power Circuit in the event of a frontal impact, operating even before the airbags are fully deployed.
The fuel tank uses a new lightweight plastic multiplex design with maximum impact resistance. Even following a 50km/h rear impact from an SUV, the fuel tank suffers no leakage.
Active safety (those systems that help you avoid an accident in the first place), include Toyota’s ‘by-wire’ Electronically Controlled Braking (ECB2), Electric Traction Control (E-TRC) and advanced Vehicle Stability Control Plus (VSC+).
The ‘by-wire’ ECB2 braking system uses brake pedal-activated electronic sensors to communicate braking feel to the driver and control the braking hydraulics. It not only generates higher hydraulic pressures than conventional systems, but it is also 17 per cent lighter.
The Electric Traction Control (E-TRC) system controls wheel slippage via ECB2 and the high-torque electric motor element of the Hybrid Synergy Drive. E-TRC is so quick in counteracting any incipient skid that the driver often won’t even be aware of its intervention. Nor will he or she hear the tyre squealing that is often associated with wheel spin.
ECB2 and E-TRC are interconnected with Vehicle Stability Control Plus (VSC+), that works with the electric power steering system to add steering torque assistance to the conventional stability control system, helping the driver get the most out of the car’s performance potential by avoiding stability-threatening situations.