Detection of checking action on parking significant for cognitive dysfunction patients

Abstract

Cognitive dysfunction patient could have symptoms such as attention disorder, execute function disorder and so on. These symptoms may cause unsafe driving in daily life. The degree of these symptoms can be evaluated by neuropsychological examination, however, the correspondence relationship between these symptoms and unsafe driving is uncertain. Therefore, it is difficult to judge the patient’s driving aptitude only by neuropsychological examination. To solve this problem, we are developing unsafe driving detection system. It requires some small wireless sensors measuring triaxial angular velocity and acceleration to be attached on user’s head, toes and steering wheel, and GPS sensor on a car. Since many of the cognitive dysfunction patients have symptom of attention disorder, it assumed that safety checking actions tend to be careless. Based on this assumption, we have analyzed the driver’s checking action on intersections and changing lane. Here discusses the result of analysis assumingly complex checking action on parking cars. When parking a car, driver must control the car and pay attention to rear, front and both side simultaneously. From the video analysis of the experiment with small wireless sensors and a real car, cognitive dysfunction patients tend to use rear view mirror to accomplish their safety checking. Especially, the right side mirror checking action was significantly high compare to the one without cognitive dysfunction. Safety checking action, accomplished only by rear view mirror is more dangerous than checking directly by turning around. On investigating of how much the attached sensors can acquire these driver’s checking actions, it was clarified that these sensors can identify only the direction of head, however cannot identify if the drivers were looking at the target object directly or through rear view mirror. It should be studied further that how much can our unsafe driving detection system distinguish direct and indirect one.