Investigations made on Riding-Up of the Lap Belt of a Safety Harness System 860052
In conjunction with a program for development of vehicle seats with integrated seat-belt systems, the feasibility of employing 4-point safety harness systems was investigated as alternative to 3-paint seat belts.
As supplemental modifications to standard-production safety harnesses-employed, for example, in racing vehicles and commercially available - possible different arrangements of lap and shoulder belts were incorporated into our investigations made, and testing was performed of these modifications to assess safety-engineering effectiveness.
Sled tests revealed significant deficiencies in safety harnesses regarding protective functions offered in an actual seat. In particular, tendencies of the lap belt to ride up, under influence of the shoulder belts, produced serious submarining effects with standard-production safety harness.
Nevertheless, 4-point safety harness can in fact be considered sufficiently safe and effective if the static lap belt is tightened extremely snugly, or if pre-load devices effectively function for the lap belt in automatic retraction (ELR) versions.