The work aims to investigate the involvement of auditory, tactile and visual multi-sensory stimuli in the care of the elderly with Alzheimer's disease, to enhance their perception of music with the help of smart hardware and software technologies, and to design a smart wearable product for the elderly with multi-sensory interaction. Based on the principles of perceptual substitution and empathy, a sensory substitution method was created to transform music into vibratory and visual information. And experimental tests were conducted to verify the feasibility of the auditory-tactile and the auditory-tactile-visual multi-sensory interaction prototypes. Adding visual design based on the integration of auditory-tactile senses can better stimulate the speech behavior ability of the elderly. A fingertip vibrating music wearable device, the Fingertip Piano, was designed based on the result of analysis on feedback from the subjects to promote active behavior by providing a multi-sensory experience that integrates touch, hearing and vision. The design of the multi-sensory interactive product is effective in improving the mood and active behavior of Alzheimer's patients and has positive implications for the physical health and living quality of elderly patients.