【作者】 高飞；

【导师】 王振龙；

【作者基本信息】 哈尔滨工业大学 ， 机械制造及其自动化， 2010， 硕士

【摘要】 仿生水下机器人以其高度灵活性及高效性的特点,成为近年来机器人领域研究的热点。目前已研制出的仿生水下机器人主要为模拟鱼类游动模式推进的仿生机器鱼。乌贼是海洋中一种奇特的动物,主要依靠喷射进行游动,其推进效率和灵活性均可与鱼类相媲美,因而极具有仿生价值。喷水推进的技术在船舶推进中应用已较为成熟,并可通过矢量喷口结构对推进方向进行控制。但传统的矢量喷口设计均采用机械传动结构实现,结构复杂,难以应用到小型仿生水下机器人上。而乌贼喷嘴结构简单,可实现柔性弯曲,从而能够灵活控制乌贼游动的方向。因此,本文从乌贼喷嘴形态结构及功能得到启发,选用形状记忆合金(Shape memory alloys,SMA)丝作为驱动器,设计并实现了可柔性弯曲的仿乌贼矢量喷嘴,为喷射推进仿生水下机器人方向控制提供了新方案。本文首先分析了乌贼喷嘴肌肉组织、动作机理以及功能,然后设计了中空式和嵌套式两种仿乌贼矢量喷嘴结构,通过理论分析,得出嵌套式结构优于中空式结构,并建立了仿乌贼矢量喷嘴弯曲时的力学模型。其次,建立了矢量喷嘴空间弯曲的几何模型,确定了SMA丝驱动器与矢量喷嘴空间弯曲角度的关系。研制了基于LM3S8962单片机的仿乌贼矢量喷嘴控制系统。最后,采用脉宽调制(Pulse Width Modulation,PWM)技术对仿乌贼矢量喷嘴进行控制。进行了开环实验研究,结果表明PWM方波周期过长会造成喷嘴振荡,不同占空比的PWM方波可控制喷嘴达到不同弯曲角度,喷嘴不同弯曲角度对应SMA丝不同电阻值。进行了半闭环实验研究,通过比例积分控制提高了系统响应速度,获得了较小的稳态误差,取得了良好的控制效果。实现了仿乌贼矢量喷嘴的矢量控制。在流速为0.8m/s的条件下进行了喷射试验,验证了其控制水流喷射方向的可行性。更多还原

【Abstract】 Due to their high degree of flexibility and efficiency characteristics, biomimetic underwater robots have become a hot research in the field of robotics in recent years. Currently, the successful developments of biomimetic underwater robots have mainly focused on the imitation of fish. Squid, strange marine animals, swim mainly by jetting water, and its propulsive efficiency and flexibility can be comparable with the fish. Therefore, there is great value of bionic. Jet propulsion technology which control jet direction through vector nozzle structure has been mature in the application of ship. However, the traditional vector nozzle design is achieved by mechanical transmission structure, so it’s difficult to apply in the small biomimetic underwater robot due to its complex structure. The structure of squid nozzle is simple, and it can bend flexible, thus it can control the direction of swimming squid. So, inspired from the structure and function of squid nozzle, this article has designed and realized the biomimetic squid vector nozzle which can be driven by shape memory alloy(SMA) and be bent flexible.First, this paper analyzes the squid nozzle muscle, action mechanism and function, and then designs two kinds of biomimetic squid vector structure. Through theoretical analysis, the nested structure is better than the hollow-type structure. And the mechanical model of the bending biomimetic squid vector is established.Second, the space curved geometry model of the biomimetic squid vector nozzle is established to determine the relationship between the SMA actuator and the space bending angle of nozzle. And the control system of the biomimetic squid vector nozzle based on the LM3S8962 MCU is developed.At last, the biomimetic squid vector nozzle is controlled using pulse width modulation(PWM) technology. Open-loop experiment is conducted, the results show that too long the PWM square wave cycle is will cause the nozzle oscillation, different bending angle of nozzle can be controlled by different duty cycle of PWM square wave, and different SMA wire resistance corresponds different bending angle. Semi-closed loop experiment is conducted, proportional integral control is used to improve the system response speed, obtain smaller steady-state error, and good control effect is achieved. Vector control is successful made, and injection test is carried out under the condition of a flow rate of 0.8m/s to verify its feasibility of control of water jet direction.更多还原