PROBLEM TO BE SOLVED: To provide a careless state decision device capable of deciding whether or not a state of a subject is a careless state, and performing the decision of the careless state with robustness against noise.SOLUTION: This careless state decision device acquires an electrocardiographic signal of a driver of a vehicle (S11), and calculates time series data of a cardiac cycle (RRI) from the electrocardiographic signal (S12). The careless state decision device detects peaks and troughs (TPs) from the time series data (S13), and calculates time series data of the TPs (S14). The careless state decision device sets a section for 3 minutes wherein a travel is stable after the vehicle enters an expressway as a reference section (S15, S16), counts the number of the TPs in the reference section (S17), and sets a threshold value for sectionalizing a normal state and a careless state based on the number (S18). The careless state decision device counts the number of the TPs detected from the time series data of the RRI for past 3 minutes (S19). When the number is smaller than the threshold value (S20: Yes), the careless state decision device decides that a state of the driver is the careless state, and notifies the careless state (S21).COPYRIGHT: (C)2013,JPO&INPIT【課題】被験者の状態が漫然状態か否かを判定でき、かつノイズに強い漫然状態の判定を行うことができる漫然状態判定装置を提供する。【解決手段】車両の運転者の心電信号を取得して(S11)、心電信号から心拍周期(RRI)の時系列データを算出する(S12)。その時系列データから、ピーク及びトラフ(TP)を検出して(S13)、TPの時系列データを算出する(S14)。車両が高速道路進入後の走行が安定している3分間の区間を基準区間として(S15、S16)、基準区間のTPの個数を計数し(S17)、その個数に基づいて平常状態と漫然状態とを区分する閾値を設定する(S18)。過去3分間のRRIの時系列データから検出されたTPの個数を計数する(S19)。その個数が閾値より小さい場合に(S20:Yes)、運転者の状態が漫然状態であるとして、漫然状態の告知を行う(S21)。【選択図】図8
