Pedestrian collision protection system and collision site detecting apparatus for use in vehicle

A collision site detecting apparatus for a vehicle, comprising:

• a line sensor including at least two conductive lines fixedly secured to one of a front surface and a rear surface of said vehicle and placed to extend in lateral directions of said vehicle in a state separated from each other by a predetermined spacing;
• and
• a detection circuit unit for detecting a quantity of electricity related to an impedance between predetermined positions of both said conductive lines,
• wherein at least one of both said conductive lines is made of a resistive material having a predetermined resistivity, and when a collision against a body occurs, the spacing between both said conductive lines is locally elastically reduced at a position of the collision and its vicinities so as to be restorable, and said impedance varies according to the collision position.

A collision position detecting apparatus for a vehicle, comprising:

• a line sensor including first and second conductive lines fixedly secured onto a front surface or rear surface of said vehicle to extend in lateral directions of said vehicle and placed to be separated from each other by a predetermined spacing in longitudinal directions of said vehicle, with at least one of said conductive lines being elastically deformed at a position of a collision against a body to be restorable to make an electrical connection with the other conductive line;
• a power supply source for applying a voltage to a predetermined position of said first conductive line;
• a pair of voltage drop detection resistive elements individually connected between both end portions of said second conductive line and a predetermined constant-potential source;
• and
• a collision position detection circuit unit for discriminating a collision position obtained on the basis of voltage drops across both said resistive elements through the use of an n-bit digital signal,
• wherein, when an electrical resistance value per unit distance of said first conductive line in said lateral directions is taken as R1, an electrical resistance value per unit distance of said second conductive line in said lateral directions is taken as R2, an electrical resistance value of both said resistive elements is taken as R3, R3/R1 is expressed as S, a constant (required resolution/sensor installation width) is taken as dx, and a maximum allowable resistance ratio is taken as T, a resistance ratio (R2/R1) is set to be below T given by the following equation. 0 < R2 R1 < ( dx + S ) ⁢ { 2 n ⁢ dxS - ( 1 - dx ) - 2 ⁢ S - S 2 } ( 1 + 2 n ⁢ S ) ⁢ ( 1 + 2 ⁢ S ) ⁢ dx = T S = R3 R1
• where dx:
• required resolution/sensor installation width
• n:
• voltage read resolution multiplier (number of bits).

A collision position detecting apparatus for a vehicle, comprising:

• a line sensor including first and second conductive lines fixedly secured onto a front surface or rear surface of said vehicle to extend in lateral directions of said vehicle and placed to be separated from each other by a predetermined spacing in longitudinal directions of said vehicle, with at least one of said conductive lines being elastically deformed at a position of a collision against a body to be restorable to make an electrical connection with the other conductive line;
• a power supply source for applying a voltage to a predetermined position of said first conductive line;
• constant current circuit units individually connected between end portions of said second conductive line and a predetermined constant-potential source;
• and
• a collision position detection circuit unit for determining a collision position on the basis of voltage drops across said constant current circuit units.