Electronic tether to tether my father's rollator to him
There does not appear to be a commercially-available product to meet such a need.
Giving him a passive RFID tag to wear and attaching a light-weight alarm to the rollator that polls the tag every few seconds might generate a workable solution, but I don't have sufficient experience with RFID to generate a solution in a reasonable time-scale. I would probably favour CMOS timers and logic over a microcontroller for similar reasons.
Does anyone have a project that could be adapted, or expertise that could be applied, to this task?