During a talk with a member of the German cryonics organization, Cryonics Germany, I was told that they had very good experiences with the Ballistocardiography (BCG) sensor model SCA11H from Murata Manufacturing. They have these sensors placed under mattresses of several people with a significant risk of dying in the near future (significant for the purpose of cryonics). These people are mainly very old and/or chronically ill.
For bedridden patients, this sensor from Murata can be configured to almost always recognize a critical issue within less than three minutes.
This reliability and fast detection time motivated me to research the topic of BCG sensors.
General Information about Ballistocardiography Sensors
Ballistocardiography is a technique for recording repetitive motions of the human body arising from the sudden ejection of blood into the great vessels with each heart beat. BCG sensors can record this data via noninvasive methods. For example, there are BCG bed sensors that can be placed onto bed frames and detect heart beats via the vibrations of the bed. These sensors can also detect breathing and other body movements.
Because people who have deanimated don't move their bodies, don't breathe and don't have a pulse, BCG bed sensors are promising for fast emergency detection.
Testing and analyzing BCG bed sensors regarding their usage as cryonics alarm devices has shown:
• Detection of pulse and breathing is not completely reliable.
• Detection of stronger body movements than pulse or breathing is almost always reliable. Unfortunately, the detection of these stronger body movements has to be disabled if the bed has a system installed that moves the person frequently to avoid the person lying sore.
SCA11H Sensor from Murata Manufacturing
SCA11H is a BCG bed sensor from Murata Manufacturing Co., Ltd.
It is a sensor that can be placed under or onto beds/mattresses for health monitoring. Cryonics Germany uses these bed sensors, and they have proven to be sufficiently reliable.
When the bed sensor detects no pulse, no breathing or no other body movements for a configurable amount of time, it notifies a Web server, which then sends a text (SMS) to configured contacts.
The sensor is no longer produced by Murata Manufacturing but, at the time of writing (2023-06-20), it is still purchasable at online shops and costs about $200 per unit. So far, Murata has not officially announced a successor product.
SleepSense Sensor from Talius
The Australian company Talius Group Limited offers a BCG bed sensor called SleepSense. This sensor is also sold by the companies Innovate Care and Tochtech Technologies under the same name, expect the second S written in lower case ("Sleepsense").
This sensor is usually placed under a bed leg or bed wheel for health monitoring. The sensor is accompanied by a mobile app and a cloud-based software system.
If the sensor detects no or irregular breathing, it sends an alert message to a configurable set of mobile phones.
Heart beats / Pulse can also be detected by this sensor. If it detects no pulse or an irregular pulse, it sends an alert message (like in the case of no breathing).
The sensor also sends an alert message even if a pulse and breathing are detected, but no stronger body movements are detected for a configurable amount of time.
Moreover, it supports alerts for cases when, at night, the resident is out of bed for a highly unusual long time.
Another feature of the device is pressure sores prevention. This is achieved by tracking of bed-time and turn movements. Using this data, the system provides real-time turn reminders and reports.
The system also offers analysis of sleep quality, including the display of sleep statistics.
The cost per unit is about $215.
Unfortunately, we were not yet able to test this device ourselves. This written analysis of the sensor and its accompanying software system is solely based on publicly available information.
Summary and Final Thoughts
BCG bed sensors can be used for reliable and fast detection of emergency problems. This makes them well suited for cryonics monitoring systems.
The SCA11H bed sensor from Murata Manufacturing and its accompanying software infrastructure have proven to be fast and reliable for emergency issue detection. Unfortunately, this sensor is no longer produced. Thus, it is not unlikely that, in several months (time of writing 2023-06-20), the sensor will be rare to find on shopping websites (including offerings as a second-hand product).
The SleepSense sensor from Talius offers more features than the SCA11H sensor from Murata. The SleepSense sensor hasn't been tested by us so far. It can be considered a very promising sensor worth to be tested, but it should not be bought with the intention of using it immediately for real-life cryonics monitoring.
Obviously, cryonics monitoring only with bed sensors is insufficient for cryonicists who spend most of their time outside their bed. Nevertheless, bed sensors can often achieve coverage of almost 24 hours per day for bedridden people. BCG bed sensors do not require the person to wear any device, and because of this, for many people they can be preferable to wearable devices like smartwatches. Moreover, in contrast to wearable devices, BCG bed sensors do not suffer from the problem that people can forget to wear the device.