A Review of Heartbeat Detection Systems for Automotive Applications

Abstract

Many accidents are caused by sudden changes in the physical conditions of professional drivers. Therefore, it is quite important that the driver monitoring system must not restrict or interfere with the driver's action. Applications that can measure a driver's heartbeat without restricting the driver's action are currently under development. In this review, examples of heartbeat-monitoring systems are discussed. In particular, methods for measuring the heartbeat through sensing devices of a wearable-type, such as wristwatch-type, ring-type, and shirt-type devices, as well as through devices of a nonwearable type, such as steering-type, seat-type, and other types of devices, are discussed. The emergence of wearable devices such as the Apple Watch is considered a turning point in the application of driver-monitoring systems. The problems associated with current smartwatch- and smartphone-based systems are discussed, as are the barriers to their practical use in vehicles. We conclude that, for the time being, detection methods using in-vehicle devices and in-vehicle cameras are expected to remain dominant, while devices that can detect health conditions and abnormalities simply by driving as usual are expected to emerge as future applications.

Keywords: driver; heartbeat monitoring system; in-vehicle; smartwatch.

Figure 1

The relation of heartbeat, HF and LF.

Figure 2

Steering-type measurement system developed by Arakawa et al.: (A) appearance of the system; (B) transmitter and receiver LEDs visible on the spoke of the steering wheel; (C) demonstration of the operation of the system while playing a driving game.

Figure 3

The system block diagram of the steering-type measurement system developed by Arakawa et al.

Figure 4

The outline of Mitani’s system.

Figure 5

A portable device-type system developed by Arakawa et al.: (A) developed portable device-type system (B) appearance of the system and interface that shows the current blood pressure; (C) demonstration of the operation of the system.

Figure 6

Portable device-type system set at the meter visor.

Figure 7

Segregation of the device for detection of heartbeat and expression. The lines connected from each block of “Detection of heartbeat” to each block of “Detection of facial expression, etc.” show the possible combination for adapting in-vehicle use.