Study on the Shooting Vibration Characteristics of a Quadruped Unmanned Combat Platform under Impact Loads

doi:10.12382/bgxb.2025.0282

Abstract

Abstract:

The quadruped unmanned combat platform holds significant military application value in future warfare due to its exceptional mobility and adaptability to complex terrains. A rigid-flexible coupled launch dynamics model is established to investigate the impact of shock loads on the vibration characteristics of the platform and firing accuracy. The amplitude, angular displacement and angular velocity variations of muzzle center point around x-axis and z-axis under different shock loads are analyzed through numerical simulation. The firing dispersion characteristics are evaluated using a six-degrees-of-freedom external ballistic model, and the live-fire tests are made on unmanned combat platforms with and without a bidirectional buffering device. The results show that the amplitude of the muzzle center point around the x-axis and z-axis during five-round bursts is significantly reduced, the vibration levels decreases, and the angular velocity tends to stabilize without the continuous increase observed in fixed connections after installing the bidirectional buffering device. The radius of 100% dispersion circle (R₁₀₀) is reduced to 86.4mm with a decrease of 34.6%. Live-fire test data indicates that R₁₀₀ for single-shot and five-round bursts is 75.7mm and 94.5mm, respectively, with the reductions of 21.1% and 32.8%. The test data are in good agreement with the simulated results, validating the accuracy of the numerical simulations. This confirms that the designed damping device effectively suppresses firing-induced vibration, significantly improving the firing stability and accuracy of the quadruped unmanned combat platform. The research findings provide technical support for the structural optimization design of unmanned combat platforms.

Key words: quadruped unmanned combat platform, vibration characteristics, shooting accuracy, rigid-flexible coupling, dynamics model

LIU Kun, FENG Ying, KANG Bao, WU Zhilin, SONG Jie, ZHU Tao. Study on the Shooting Vibration Characteristics of a Quadruped Unmanned Combat Platform under Impact Loads[J]. Acta Armamentarii, 2025, 46(10): 250282-.

Figures/Tables 30

Fig.1 Overall structure of quadruped unmanned combat platform

Fig.2 Composition of each system

Fig.3 Mesh model

Fig.4 Rigid-flexible coupling model of quadruped unmanned combat platform

Fig.5 Single-shot pressure-time curve

Fig.6 Five-round burst pressure-time curve

Fig.7 Coordinate system for muzzle vibration analysis

Fig.8 Amplitude variation of muzzle center point along x-axis and z-axis during five-five-round bursts

Table 1 The vibration characteristics of muzzle center point at the instant of bullet exit during a five-round burst firing

振动特性	第1发	第2发	第3发	第4发	第5发
x轴方向振幅/mm	0.08	1.1	3.1	3.1	0.9
z轴方向振幅/mm	0.51	3.1	4.4	3.4	6.3
射击振动量/mm	0.516	3.289	5.382	4.601	6.364

Table 2 Angular displacement of muzzle center point along x-axis and z-axis

角位移	第1发	第2发	第3发	第4发	第5发
x轴方向角位移/(°)	0.002	0.028	0.081	0.081	0.02
z轴方向角位移/(°)	0.013	0.08	0.12	0.09	0.164

Fig.9 Angular velocity variation of muzzle center point about x-axis

Fig.10 Angular velocity variation of the muzzle center point around z-axis

Fig.11 Theoretical results of bullet impact point distribution for 5-round burst firing in fixed connection mode

Fig.12 Bidirectional buffering device

Fig.13 Weapon platform equipped with a bidirectional buffering device

Fig.14 Travel variation patterns of bidirectional buffering device with three different stiffness levels

Fig.15 Force variation pattern of spring with a stiffness of 250N/mm

Fig.16 Amplitude variation of muzzle center point along x-axis and z-axis during 5-round burst firing

Table 3 The vibration characteristics of muzzle center point at the instant of bullet exit during a five-round burst firing

振动特性	第1发	第2发	第3发	第4发	第5发
x方向振幅/mm	0.1	0.4	1.9	2.1	0.8
z方向振幅/mm	0.3	1.5	3.1	2.5	3.1
振动量/mm	0.32	1.55	3.64	3.26	3.20

Table 4 Angular displacement of muzzle center point along x-axis and z-axis

角位移	第1发	第2发	第3发	第4发	第5发
x轴方向角位移/(°)	0.003	0.039	0.081	0.065	0.081
z轴方向角位移/(°)	0.008	0.08	0.12	0.09	0.164

Fig.17 Angular velocity variation of muzzle center point around x-axis

Fig.18 Angular velocity variation of muzzle center point around z-axis

Fig.19 Impact point distribution of five-round burst with buffering device

Fig.20 Experimental weapons and ammunition

Fig.21 Experimental principle

Fig.22 Experimental scene setup

Fig.23 Experimental results of impact point distribution of 5-round bursts under fixed connection conditions

Fig.24 Experimental results of 10 single-shot impact point distribution under fixed connection conditions

Fig.25 Experimental results of impact point distribution of 5-round burst with buffering device

Fig.26 Experimental results of 10 single-shot dispersion pattern with buffering device

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