## 1 Introduction  
Under-body blast (UBB) events caused by buried landmines or improvised explosive devices (IEDs) can produce rapid vertical accelerations transmitted through the vehicle floor into the occupant's lower limbs, pelvis, and ultimately the spine, resulting in complex and severe loading of the head-neck system. The vertical accelerations can result in compressive axial loads and inertial bending moments in the cervical spine, increasing the risk of skull base fractures, cervical vertebral damage, and traumatic brain injury (TBI). Non-penetrative occupant injuries represent the common casualty pattern in armored vehicles surviving mine detonations, where hull integrity remains preserved. In this scenario, the blast wave fails to penetrate the vehicle hull to directly injure occupants. Primary injury mechanisms originate from vehicle transmissibility, generating traumatic impacts through structural vibration. The simulation and analysis of selected blast scenarios have been the focus of several studies. [PERSON] [1] developed a blast buck (Accelerative Loading Fixture, or ALF) for studying under-body blast events in a laboratory to compare the responses of Hybrid III and PMHS in the explosion. [PERSON] [2] conducted a finite element analysis to investigate the blast response of the V-shaped hull structure in light armored vehicles. [PERSON] [3] developed a finite element model of the Hybrid III dummy under pipeline explosion environment and established the relationship between head injury and the blast propagation radius. The use of dummies for testing the non-penetrative occupant injuries of landmine explosions holds significant scientific value and practical importance. A dummy can simulate the biomechanical responses of the human body under blast impacts, thereby providing injury data. Through dummy testing, it is possible to quantify the extent of damage caused to occupants by blast impacts, evaluate the effectiveness of vehicle protection systems, and provide a basis for improving vehicle design and materials. Due to the high biofidelity of the dummy, it is already widely used in automobile, manned spaceflight, and military protection tests. For example, Hybrid III 50 th ATD (Anthropomorphic Test Device) is used by the North Atlantic Treaty Organization (NATO) as a dummy to test explosion damage to occupants, so it is currently a mature means of explosion-damage test [4,5]. Many scholars have studied the response of Hybrid III under impact. [PERSON] [6] and [PERSON] [7,8] compared the response of the Hybrid III and the PHMS in under-body high-velocity impact. Using the Hybrid III dummy, [PERSON] analyzed occupant safety in blast-mine loading under vehicles [9], and [PERSON] investigated the protective effects of different protective clothing on the head and neck under a C4 explosion [10]. [PERSON] conducted a study on the influence of wearing protective equipment on the injuries sustained by vehicle occupants during vertical under-vehicle blast impacts [11]. Subsequently, the higher biofidelity dummies, Thor and WIAMan, were launched. Compared with Hybrid III, the flexibility of thoracic and vertebral joints and chest and shoulder restraints of THOR were increased. WIAMan is designed to be more suitable for testing under-body explosion damage, as its structure and materials more closely resemble human characteristics [12]. [PERSON] compared the response of Thor, WIAMan, and Hybrid III in under-body blast impact [13]. These high biofidelity dummies make the structure and size and biomechanical response as similar as possible to the human body, but the manufacturing cost is high. However, high biofidelity dummies are very expensive. For example, a full Hybrid III 50 th percentile male ATD generally costs approximately $250,000, depending on configuration and sensor instrumentation. When large-scale use of dummies is required--such as assessing occupant injuries at multiple seating positions within a vehicle--the use of high-fidelity dummies inevitably leads to substantial cost.