Patent Description:
The present invention is directed to dead man's control systems, also called sometimes "Driver's Safety Devices", that are automatically operated in case an operator of a vehicle incorporating the dead man's control system becomes incapacitated. Dead man's control systems usually aim to stop the vehicle operated by said operator in order to prevent any harmful situation as soon as a critical situation occurs regarding the capacity of the operator to drive said vehicle.

Dead man's control systems may equip different kind of vehicles. Indeed, vehicle according to the present invention might be guided vehicles, i.e. a device for carrying or transporting substances, objects or individuals that is guided by at least one guiding means, such as a rail, and which refer more particularly to public transport means such as buses, trolleybuses, streetcars, subways, trains or train units, etc., as well as load transporting means such as, for example, overhead traveling cranes or mining transportation means, or aircrafts, or any moving vehicle that comprises an operator in charge of driving said vehicle. The dead man's control system is in charge of making sure the operator driving said vehicle is fully conscious.

Examples of dead man's control systems are for instance:.

The prior art dead man's control systems all require an active action or reaction from the vehicle operator. This might lead to some failures of the system, for instance in the case the vehicle operator is unconscious, but still touching the above-mentioned capacitive touch sensor. For example, <CIT> relates to a system for monitoring, recording and/ or analyzing vigilance, alertness or wakefulness and/or a stressed state of an operator of equipment or machinery in a variety of situations including situations wherein the degree of vigilance of the operator has implications for the safety or well being of the operator or other persons.

An objective of the present invention is to provide a safer dead man's control system and method compared to the known prior art systems and methods.

The aforementioned objective is achieved by a dead man's control system and a method according to the independent claims. Further embodiments and other advantages of the present invention are proposed in the dependent claims.

The invention proposes in particular a dead man's control system, configured for being installed on-board a vehicle designed for being operated by an operator, for instance from an operator cabin, the dead man's control system being configured for checking a capacity of the vehicle operator to operate said vehicle and comprising:.

The processing unit is in particular able to determine a presence or absence of at least one of the operators in said operator cabin from its analysis of said pulsation rate data and/or movement detection data and for automatically triggering said safety system in case of an absence of at least one of said operators or a driving incapacity of each operator remaining inside the cabin.

The present invention concerns also a dead man's control method capable of detecting in real time a driving incapacity of an operator of a vehicle during operation or driving of said vehicle by said operator, the method comprising:.

Further aspects and advantages of the present invention will be better understood through the following drawings, wherein like numerals are used for like and corresponding parts:.

<FIG> shows a vehicle <NUM> equipped with a preferred embodiment of a dead man's control system according to the invention, and whose task is to control a capacity of a vehicle operator <NUM> or driver to operate or drive said vehicle <NUM>.

The dead man's control system might be installed on board the vehicle <NUM>, e.g. in an operator cabin that is closed by a door <NUM> from the rest of the vehicle, the locking of said door being for instance controlled by a locking system, said door <NUM> physically separating for instance the operator <NUM> from passengers of the vehicle <NUM>. The dead man's control system might also equip a remote control cabin that is configured for remotely controlling the vehicle <NUM>.

The dead man's control system according to the invention typically comprises a pulsation rate measurement device <NUM> and a movement detection device <NUM>, wherein the movement detection device <NUM> may comprise an accelerometer <NUM> and/or a camera system that may comprise a first camera <NUM> and a second camera <NUM>. The cameras <NUM>, <NUM> of the camera system are preferentially installed inside the operator cabin in order to acquire images of the operator <NUM>, said camera system being configured for enabling a check of the capacity of the operator <NUM> to drive the vehicle <NUM> from positions or change of positions of the operator on his seat. For instance, the first camera <NUM> is positioned in the cabin for pointing to the operator's side and the second camera <NUM> is positioned in the cabin for pointing to the operator's face. Preferentially, the dead man's control system comprises a portable device <NUM> that comprises itself the accelerometer <NUM> and the pulsation rate device <NUM>. Said portable device <NUM> might be worn by the operator <NUM>, e.g. being a wristband wearable on his wrist. Preferentially said portable device <NUM> is configured for being worn on a body part of the operator which is moving during the driving of the vehicle and which motion controls the driving or operation of the vehicle. Preferentially, the portable device <NUM> is able to wirelessly communicate with the processing unit <NUM> in order to provide to said processing unit the pulsation rate data and a first set of movement detection data originating from the accelerometer <NUM>.

The movement detection system <NUM> and the pulsation rate device <NUM> are configured for outputting in real time respectively movement detection data and pulsation rate data which are usable for determining respectively a change of position of at least one body part of the operator and the heartbeat of said operator by means of a processing unit <NUM>. Typically, the pulsation rate device is configured for measuring heartbeat in said body part, e.g. from blood motion, using well known non-invasive techniques, for instance by using infrared light. For instance, when incorporated to the portable device <NUM> being a wristband, the pulsation rate device is able to measure heart pulsations at said wrist of the operator. Then, the processing unit <NUM> according to the invention is configured for analyzing in real time the pulsation rate data and the movement detection data, in order to automatically trigger a safety system <NUM> of the vehicle <NUM> if preconfigured conditions regarding the movement detection data and the pulsation rate data are not fulfilled. In other words, the processing unit <NUM> is able to analyze the pulsation rate data and the movement detection data and to determine, in function of said analysis, if said safety system <NUM> has to be triggered or not. In particular, the triggering of the safety system <NUM> is configured for carrying out at least one of the following actions:.

According to the present invention, the movement detection system <NUM> is able to detect at least a change of position of said body part of the operator <NUM>, in particular by means of said accelerometer <NUM>. Additionally and optionally, the first camera <NUM> is able to provide images enabling analysis by the processing unit <NUM> of the operator's position in its seat <NUM> as well as body motion, and the second camera <NUM> is configured for providing images suitable for an analysis by the processing unit <NUM> of the operator's head alignment and face gestures. In particular, the movement detection data comprise said first set of data and a second set of data, wherein the first set of data is provided by said accelerometer and will be called "accelerometer" data, while the second set of data are data provided by the camera system, for instance by the first camera <NUM> and the second camera <NUM>, and will be called "video data". In other words, the second set of data that are video data encoding images acquired in real time by the video system and provided in real time to the processing unit <NUM>. Preferentially, the video data might be used by the processing unit <NUM> for the determination of an absence or presence of the operator in the cabin. For this purpose, the processing unit might use algorithms for the detection of person.

The conditions verified by the processing unit <NUM> and required for triggering the safety system <NUM> by means of said processing unit will be now described in more details. According to the present invention, the triggering of the safety system <NUM> by the processing unit <NUM> is preferentially configured for activating the emergency brake system <NUM> when at least the following situations occur:.

By "correct", or "incorrect" position, it has to be understood that the processing unit <NUM> is able to determine from the second set of data if the position of the operator in his seat, his head alignment with his body and a face gesture correspond to a normal situation wherein the operator is conscious and capable of driving the vehicle or to an abnormal situation wherein the operator is not anymore capable of driving the vehicle. Learning algorithms might be used for the classification of the second set of data in a first class that groups the so-called "normal situations" or in a second class that groups the so-called "abnormal situations". Such learning algorithm are known by the skilled person and not described here. By normal or abnormal pulsation, it has to be understood that the processing unit is configured for determining if the heartbeat of the operator belongs to the so called "normal situations" or "abnormal situations". For this purpose, the processing unit might comprise in a database pulsation rate threshold defined for each operator of the vehicle, as well as historical measurements of pulsation rate for each of the operators, for instance specific pulse rate patterns for each operator, and uses comparison with said threshold and/or historical measurements for determining if an actual pulsation rate shall belong to a normal situation or to an abnormal situation. Optionally, pulse rate patterns defined for each operator might be used for automatically identifying an operator and activating the locking system of the door, for instance for automatically opening the door when said operator is identified, prohibiting therefore access to the cabin to non-identified operators.

According to the present invention, the triggering of the safety system <NUM> by the processing unit <NUM> is preferentially configured for activating an alert for the operator, e.g. using a buzz, a bell, or vibrating or luminous mechanisms, making for instance the portable device <NUM> vibrating, when at least the following situations occur:.

Preferentially, after another predetermined period of time following a triggering of the safety system that is configured for activating an alert for the operator, the dead man's control system according to the invention is configured for rechecking the pulsation rate data and movement detection data, and if the situation exposed under (e)-(f) did not change, or if a situation falling under the conditions previously exposed under (a)-(d) occurs, then the processing unit is configured for performing another triggering of the safety system <NUM> wherein said other triggering is configured for activating the emergency brake system <NUM>.

Optionally, the triggering of the safety system <NUM> by the processing unit <NUM> is configured for deactivating the locking system of the door <NUM> of the operator cabin if the processing unit <NUM> determines that there is no pulsation from the pulsation rate data and/or there is an incorrect body position from the second set of data. Such situations might occur if the operator left the cabin, or if the operator is in an incapacity state regarding the driving of the vehicle. Advantageously, this ensures having access to the cabin in case of critical situations involving an operator.

According to the present invention, the processing unit <NUM> is configured for correlating the pulsation rate data, the first set of data and the second set of data in order to determine in real time if the operator is capable (normal situation) or not (abnormal situation) of operating the vehicle. Preferentially, learning algorithm are used for improving the speed of the detection of the situation (i.e. of classifying the situation in the class of a "normal situation" or in the class of an "abnormal situation") in order to trigger the right action regarding the safety system <NUM>. In particular, if the processing unit determines that the pulsation of the operator is normal from said pulsation rate data, that a movement of said body part occurs from said first set of data and that the body position of the operator is correct from said second set of data, then the processing unit is configured for not triggering the safety device, since the situation is normal and the operator is conscious and fully capable of driving said vehicle.

Claim 1:
Dead man's control system configured for checking a capacity of an operator (<NUM>) to operate or drive a vehicle (<NUM>), the dead man's control system comprising:
- a pulsation rate measurement device (<NUM>) configured for measuring heartbeat of the operator (<NUM>) and outputting in real time pulsation rate data;
- a movement detection system (<NUM>) for detecting a change of position of at least one part of the body of the operator (<NUM>) and outputting in real time movement detection data, wherein the movement detection system (<NUM>) comprises a camera system comprising at least one camera (<NUM>, <NUM>) configured for being installed inside the operator cabin in order to acquire images of the operator, said camera system being configured for enabling a check of the capacity of the operator to drive the vehicle (<NUM>), the movement detection data comprising a second set of data that are video data encoding the acquired images provided in real time to the processing unit (<NUM>);
- a processing unit (<NUM>) for analyzing in real time the pulsation rate data and the movement detection data, wherein the processing unit (<NUM>) is configured for automatically triggering a safety system (<NUM>) of the vehicle in function of its analysis of the pulsation rate data and the movement detection data wherein the triggering of the safety system (<NUM>) by the processing unit (<NUM>) is configured for deactivating a locking system of a door (<NUM>) of the operator cabin if the processing unit (<NUM>) determines that there is no pulsation from the pulsation rate data and/or there is an incorrect body position from the second set of data.