摘要
形状记忆合金是一种高效的驱动器。当使用形状记忆合金以较大的驱动力和驱动行程进行双向驱动时,需要增加偏置机构来完成对称动作。使用弹簧等作为偏置机构时,需要有持续能源输入维持变形。为克服这种缺陷,利用形状记忆合金单程记忆效应,以链轮链条传动机构作为依托,提出一种基于应变约束条件的旋转驱动器的结构设计方法。结构中以形状记忆合金作为无需能量输入的偏置机构,实现在单程记忆效应下的大行程双向驱动,并可消除链轮链条传动间隙。根据这种结构的特征,给出结构几何参数的设计公式及输出转矩公式,通过试验的方法研究旋转驱动器中形状记忆合金在应变约束条件下的应力应变特征,给出驱动过程中存在的应变死区,修正转角设计函数。
Shape memory alloys（SMA） are highly active actuators.When shape memory alloys are used to realize a two-way actuation with a large driving force and a long driving stroke,a bias mechanism should be added to finish the symmetrical movement.When a spring is used as a bias mechanism,continuous energy input is required to keep the deformation.To overcome this shortcoming,a structural design method of rotation gear actuated by shape memory alloys based on constraint condition of strain is put forward.The structure is realized by sprocket feed and one-way shape memory effect and a two-way actuation is finished by the bias mechanism made up of shape memory alloy itself.Space of sprocket drive can be erased by the contraction of SMA.According to the feature of this structure,the formulas of geometric parameter design and torque are given.Under the constraint condition of strain,relations between stress and strain of shape memory alloys are studied through experiment.A strain dead zone existing during the actuation is given and an angle design function is corrected.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2010年第14期91-94,100,共5页
Journal of Mechanical Engineering
关键词
形状记忆合金
形状记忆效应
链条
结构设计
Shape memory alloys（SMA） Shape memory effect Chain Structural design
