A novel U-shaped stepping linear piezoelectric actuator with two driving feet and low motion coupling: Design, modeling and experiments

•A U-shaped stepping linear piezoelectric actuator with two driving feet is proposed.•The measured output displacement motion coupling ratio of the prototype is only 4%.•The developed static models can predict the step lengths and clamping force well.•The prototype achieves maximum thrust force and speed of 189.7 N and 273.4 μm/s.