深海AUV无动力垂直下潜运动特性研究

Research on characteristics of unpowered vertical diving motion of deep-sea autonomous underwater vehicle

深海AUV(自主水下机器人)采用无动力下潜方式能有效节约能源,但是水平或小纵倾角姿态下潜用时较长,水平偏移大。为提高下潜速度,减小下潜偏移距离,对AUV无动力垂直下潜过程进行研究。使用四元数代替欧拉角得到AUV运动方程,并加入洋流和浮力数学模型,通过Simulink仿真模块建立AUV垂直下潜运动仿真方法,解决垂直下潜产生的姿态角解算奇异性问题。通过设置不同仿真工况,得到AUV垂直下潜运动状态量受负浮力、重浮心距离、舵角、初始纵倾角及环境扰动力的作用规律。结果表明,AUV采用垂直下潜方式,可实现较大的下潜速度,同时减小水平偏移距离;洋流扰动是垂直下潜运动产生水平偏移的主要原因;下潜深度6000 m时,浮力变化扰动导致末端下潜速度减小30%,下潜时间增加21%。

Unpowered diving for deep-sea AUV(autonomous underwater vehicle) can effectively save energy.But it takes a long time to submerge in horizontal or small pitch attitudes,resulting in large horizontal drift.To improve the diving velocity and reduce the diving offset distance,the unpowered vertical diving motion of AUV was studied.To obtain the AUV motion equation using quaternions instead of Euler angles and incorporating ocean currents and buoyancy mathematical models,the motion simulation method of vertical diving for AUV is established though the Simulink simulation module.It solves the singularity problem of attitude angle solution caused by vertical diving.By setting different simulation conditions,the effects of negative buoyancy,distance between the center of gravity and the center of buoyancy,rudder angle,initial pitch angle,and environmental disturbance on the AUV vertical diving motion are obtained.The results show that the AUV can achieve a higher diving velocity and reduce the horizontal drift distance by using the vertical diving method;ocean current disturbance is the main cause of horizontal drift during vertical diving motion;when diving at a depth of 6 000 m,the disturbance of buoyancy changes results in the terminal diving velocity decreasing by 30% and the diving time increasing by 21%.