The Covid-19 pandemic was devastating to public health, but it also stimulated the development of new technologies hoping to re-establish our social connections. I met Claude Goodman in March 2020, learned of his CareBank project, and gladly took on the challenge of developing improved wireless sensors for that system.
The concept of a Bluetooth Low Energy module and motion sensor was not unusual, but long-range transmission, long battery life, and ease of battery replacement by an elder were more demanding requirements. We used BLE 5.1 and careful antenna design to extend the range and a low data rate to achieve >1yr of battery life. To change the battery, the user just slips off a silicone band (blue band in the rendering) and slides a new coin cell battery into a slot.