Inflatable curtain

A method for determining a pressure to which to inflate an inflatable vehicle occupant protection device inflatable between the side structure of a vehicle and a vehicle occupant, said method comprising the steps of:

• determining a velocity at or below which it is desired to prevent-a head having a given mass from striking the side structure through a thickness of the inflatable vehicle occupant protection device;
• selecting a plurality of sample inflated thicknesses;
• determining for each of said sample inflated thicknesses a corresponding required inflation pressure, said required inflation pressure being just sufficient to prevent a head travelling at or below said determined velocity from striking the side structure through an inflatable vehicle occupant protection device having said sample inflated thickness;
• determining an equation that expresses pressure as a function of thickness, said equation being determined such that said equation when solved for each of said sample inflated thicknesses provides a corresponding one of said required inflation pressures;
• and
• using said equation to determine the pressure to which to inflate the inflatable vehicle occupant protection device as a function of said thickness.

A method for determining a pressure to which to inflate an inflatable vehicle occupant protection device inflatable between the side structure of a vehicle and a vehicle occupant, said method comprising the steps of:

• determining a velocity at or below which it is desired to prevent a head having a given mass from striking the side structure through a thickness of the inflatable vehicle occupant protection device;
• selecting a plurality of sample inflated thicknesses;
• determining for each of said sample inflated thicknesses a corresponding inflation pressure, said required inflation pressure being just sufficient to prevent a head travelling at or below said determined velocity from striking the side structure through an inflatable vehicle occupant protection device having said sample inflated thickness;
• generating a plot that plots each of said sample inflated thicknesses versus its respective required inflation pressure;
• fitting a curve to said plot;
• and
• determining the pressure to which to inflate said inflatable vehicle occupant protection device using said curve.

A method for helping to protect an occupant of a vehicle that has a side structure and a roof, said method comprising the steps of:

• providing an inflatable vehicle occupant protection device that is inflatable away from the vehicle roof into a position between the side structure of the vehicle and a vehicle occupant, said inflatable vehicle occupant protection device comprising overlying panels that are interconnected to define an inflatable volume of said inflatable vehicle occupant protection device;
• determining a pressure to which to inflate said inflatable vehicle occupant protection device;
• providing an inflation fluid source for providing inflation fluid to said inflatable volume to inflate said inflatable vehicle occupant protection device to at least said pressure;
• and
• determining a thickness for said inflatable vehicle occupant protection device as a function of said pressure and of a velocity at which a head having a given mass may impact said inflatable vehicle occupant protection device, said thickness being measured between overlying points on said overlying panels when said inflatable vehicle occupant protection device is inflated at a location where a head may contact said inflatable vehicle occupant protection device, said thickness being sufficient to prevent the head from striking the side structure through said inflatable vehicle occupant protection device when said inflatable vehicle occupant protection device is inflated to said pressure and the head impacts said inflatable vehicle occupant protection device at or below said velocity.

A method for determining a thickness for an inflatable vehicle occupant protection device inflatable between the side structure of a vehicle and a vehicle occupant to a given pressure, said method comprising the steps of:

• determining a velocity at or below which it is desired to prevent a head having a given mass from striking the side structure through the thickness of the inflatable vehicle occupant protection device;
• selecting a plurality of sample inflated thicknesses;
• determining for each of said sample inflated thicknesses a corresponding required inflation pressure, said required inflation pressure being just sufficient to prevent a head travelling at or below said determined velocity from striking the side structure through an inflatable vehicle occupant protection device having said sample inflated thickness;
• determining an equation that expresses pressure as a function of thickness, said equation being determined such that said equation when solved for each of said sample inflated thicknesses provides a corresponding one of said required inflation pressures;
• and
• using said equation to determine the thickness to which to inflate the inflatable vehicle occupant protection device as a function of the given pressure.

A method for determining a thickness for an inflatable vehicle occupant protection device inflatable between the side structure of a vehicle and a vehicle occupant to a given pressure, said method comprising the steps of:

• determining a velocity at or below which it is desired to prevent a head having a given mass from striking the side structure through the thickness of the inflatable vehicle occupant protection device;
• selecting a plurality of sample inflated thicknesses;
• determining for each of said sample inflated thicknesses a corresponding required inflation pressure, said required inflation pressure being just sufficient to prevent a head travelling at or below said determined velocity from striking the side structure through an inflatable vehicle occupant protection device having said sample inflated thickness;
• generating a plot that plots each of said sample inflated thicknesses versus its respective required inflation pressure;
• fitting a curve to said plot;
• and
• determining said thickness for said inflatable vehicle occupant protection device using said curve.