×

Method and device for measuring jump-lengths on a ski-jump

  • US 4,089,057 A
  • Filed: 01/17/1977
  • Issued: 05/09/1978
  • Est. Priority Date: 01/17/1977
  • Status: Expired due to Term
First Claim
Patent Images

1. A method for measuring the jump-length of a skier who moves on skis along a ski-jump to land along a course at ground level, the skier having shock sensitive radio transmission means mounted to one of his skis, stationery radio receiver means located along the course for receipt of signals from said radio transmission means, said course including at least first and second spaced optical units adapted to emit respective optical beams across said course normal to the direction of travel of the skier along the ground after a jump has been made, each optical unit having a separate identification code, an electronic unit including time determination means, means for measuring the skier'"'"'s speed of travel along the course, said electronic unit and said means for measuring the skier'"'"'s speed being interconnected to said optical units and said radio receiver and a display unit connected to said electronic unit, said method comprising the steps of:

  • (a) initiating a radio transmission pulse from said shock sensitive transmission means upon impact of the skier'"'"'s ski on the ground;

    (b) recording the elasped time from the initiation of said radio transmission pulse until interruption by the skier of the beam emitted by said first optical unit,(c) calculating the ski-jump length from data including, the number of pulses received from the shock sensitive transmission means after impact of the skier'"'"'s ski on the ground until the skier interrupts the beam of the first optical unit, the number of pulses received between interruption by the skier of the beam of the first optical unit and interruption of the beam of the second optical unit, the number of pulses between impact of the skier'"'"'s leg which first touches the ground until interruption of the beam emitted by the first optical unit, the number of pulses between the impact of the skier'"'"'s leg which next touches the ground until interruption of the beam of the first optical unit, said calculation being made in accordance with the formula ##EQU2## where r = reference measure for the distance between the beginning of the ski jump course and the first optical unit,nx = number of pulses between the impact of the first leg of the skier on the ground and interruption of the beam from the first optical unit by that leg,nk = the number of pulses between the landing of the skier'"'"'s leg which next touches ground and interruption of the beam of the first optical unit by that leg,ns = number of pulses between the interruption of beams of the first and second optical units respectively,N = figure calculated from the identification code from the optical unit first passed,L = jump length of skier,s = distance between two subsequent optical units;

    (d) displaying the ski jump length on a display unit.

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×