RESTRAINT SYSTEM ANALYSIS FOR THE ARMORED FIGHTING VEHICLE TO REDUCE THE OCCUPANT INJURY RISK

• Main Author: Gilang Pribadi Putra P, Mikhael
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/52121
• Institution: Institut Teknologi Bandung

Mines attack and improvised explosive device is a serious threat to military personnel deployed in conflict zone. This kind of attack could cause injuries to occupants in an armored vehicle. To avoid fatalities, occupant safety had to be taken into consideration. In this research, additional pretensioner is added into restraint system in existing seat design utilized on amored vehicle with hypothesis of pretensioner addition could reduce level of occupant’s injuries. The focuses of this research are the effect of footrest height, effect of pretensioner addition in lap belt, effect of pretensioner addition in shoulder belt, and the combination between both kind of the pretensioners. The benchmark of this research in this reserch is Injury Assessment Reference Value (IARV) which evaluate the quantification of injuries. IARV used in this research is published in Allied Engineering Publication (AEP) 55 volume 5. The blast load used in this research is equivalent of 8 kg TNT which placed below the middle part of the vehicle to emulate NATO STANAG 4569 level 3b condition. Numerical model utilized Anthropomorphic Test Device (ATD) Hybrid III 50th percentile to represent the occupant. This research is segmented into four part which are (1) References study, (2) baseline model numerical analysis, (3) pretensioner addition numerical analysis, and (4) model modification to satisfy IARV on NATO STANAG 4569 level 3b condition. Footrest heights studied in this research are 100 mm, 120 mm, 140 mm, and 160 mm. Pretensioner pull lengths or Lfed studied are 20 mm, 40 mm, 60 mm, 80 mm, and 100 mm. Pretensioner triggered on 10 ms while retractor locked on 1 ms. The research shows that lap belt pretensioner could reduce HIC up to 94.49% while the effect is varied on tibia injuries between -18.8% to +14.6% but could not substitute for footrest height addition. So far, Lfed have varied result on the injury criteria. Shoulder belt pretensioner could reduce HIC up to 69.7% but not enough to pass IARV. Shoulder belt pretensioner could reduce neck compression (Fz-) for up to 25% but could also increased them. Shoulder belt pretensioner could reduce tibia compression at footrest height of 160 mm to value below IARV while relative constant when Lfed increased. In general, the combination between the two kind of pretensioner have negative effects on lap belt pretensioner effectiveness but could limitedly reduce neck compression. According to this research, it is recommended to change the footrest height to 160 mm for improved ergonomic and adding retractor-pretensioner for shoulder belt to fulfill tibia IARV requirement. to change the footrest height to 160 mm for improved ergonomic and adding retractor-pretensioner for shoulder belt to fulfill tibia IARV requirement.