Vehicle primary safety and Heavy Goods Vehicle HGV secondary safety.

The paper describes research undertaken on car and lorry anti-lock braking, vehicle lighting and signalling and lorry front underrunguards. In the braking work, decelerations on wet and dry road surfaces under emergency braking conditions are shown for various anti-lock systems comparing performance with and without the systems connected. The effectiveness of car anti-lock in allowing cornering while braking hard is also demonstrated as is the effectiveness of the lorry systems in preventing jack-knifing and trailer swing. The past, present and future aspects of vehicle lighting and signalling are discussed. Topics covered include a random survey measuring light output from vehicles on the road and the interactive driving simulator being developed at TRRL to use computer generated drivers' eye views. Future developments considered here include ultra-violet main beam lights, high intensity discharge dipped beams and automatic switching control. Front underrun guards for lorries are shown to be effective in protecting seat belted car occupants in car front to lorry front impacts at closing speeds up to 64 km/h. It is estimated that between 50 and 80 lives each year could be saved by front guards. (A) For the covering abstract of the conference, see IRRD 840727.