Abstract: The multimedia demonstration instrument has become an indispensable tool for college teaching. However, its unreasonable design causes more than 75% of teachers to suffer from cervical spondylosis, frozen shoulder and other diseases. Based on the ergonomics theory, through practical measurement and investigation, the multimedia demonstration instrument parameter optimization design is completed. Now that the instrument becomes simple and easy to use, safe and efficient, the teaching environment of college teachers is improved. 260 in-service college teachers are selected as sample population, through questionnaire survey, body percentile measurement and parameter calculation, the rule of teachers in class operation is summed up, then the total design of demonstration instrument is carried out, including human dimension analysis, user interface design, functional operation interface design, microphone design, top head design, device interface and system operating area design, overall size design and physical model design. The results of simulation test and model test show that the parameters of demonstration instrument are in line with teachers’ class operation state. Total design resets the man-machine safety dimension, increases a dual-use lifting chair by opening and closing, innovates the demonstration screen, and improves the overall structure and function of demonstration instrument, thus promoting the innovative design and reform of educational facilities.

Key words: Man-machine engineering, Multimedia demonstration instrument, Parameter optimization, Total design