Smart watch hearing aid ~

Program a smart watch to listen for specific voices or key words. Then
have them vibrate an alert until the person acknowledges it. Great use
for deaf people with children or grandchildren.

Sonic dispersement drone ~

Mount subwoofers on a box robot and have it play subsonic deep pitched
sounds to disturb people enough so they go somewhere to get away from
it. It could be autonomous and roll around a homeless settlement until
they leave.

Shoulder pad solar packs ~

Shoulder pads with clear pockets to solar battery bricks in. Perfect
for hikers and walkers to capture energy for their devices.

Screw drive pooper scooper ~

Tube with a motor connected to a long screw drive going down through
it. Put the tube over the turd and run the motor to use the screw
drive to lift the poop into the tube.