Human–machine interaction (HMI) establishes an interconnected bridge between humans and robots and plays a significant role in industry and medical fields. However, the conventional interface is bulky and rigid with a single function. It lacks feedback information to be provided to the user, limiting its application scenarios and the ability to complete complex tasks in a dynamic environment. Herein, a flexible bidirectional (FBD) interface with integrated multimodal sensing and haptic feedback and the development of an FBD-based closed-loop HMI platform are presented. The proposed FBD interface offers programmable haptic feedback through a coin vibration motor array to endow the user with better performance in missions. The multimodal sensing array can perceive signals of joint movement and the pressure imposed on the skin. In addition, the FBD interface exhibits significant advantages of flexibility and a compact structure. The experimental tests verify that the multimodal sensing module can accurately perceive various static and dynamic movements of a human. Furthermore, the actuation module can provide diverse haptic vibrations to convey different information to the user. Moreover, successful applications in the scenarios of bilateral robotic teleoperation and assistance of disabled people indicate great potential of the FBD interface for broad applications.