It is known that road roughness make drivers feel uncomfortable and sometimes has an effect on their deriving behavior. There are several researches on the influence of road roughness; however, most of them focus on the amplitude of vibration caused by the roughness. To investigate the response of the driver, electromyography (EMG) of brachioradialis and flexor digitorum superficialis, is utilized to evaluate the response of the driver to the road roughness. In the experiment using a real car, the EMG of the driver was measured when driving on the rough and the flat road. The results show the muscle activities increase in travelling on the rough road.
