This monograph presents innovative research regarding the body experience of human individuals who are using assistive robotic devices such as wearable robots or teleoperation systems. The focus is set on human-in-the-loop experiments that help to empirically evaluate how users experience devices. Moreover, these experiments allow for further examination of the underlying mechanisms of body experience through extending existing psychological paradigms, e.g., by disentangling tactile feedback from contacts. Besides reporting and discussing psychological examinations, the influence of various aspects of engineering design is investigated, e.g., different implementations of haptic interfaces or robot control. As haptics are of paramount importance in this tight type of human-robot interaction, it is explored with respect to modality as well as temporal and spatial effects. The first part of the book motivates the research topic and gives an in-depth analysis of the experimental requirements. The second and third part present experimental designs and studies of human-robot body experience regarding the upper and lower limbs as well as cognitive models to predict them. The fourth part discusses a multitude of design considerations and provides directions to guide future research on bidirectional human-machine interfaces and non-functional haptic feedback.