Badminton is a fun sport to pick up. You don’t always need a practice partner to work on your game. Take Baddy for instance. It is an open source badminton robot that can be programmed to play random or specific sequences to improve your game. You will be able to use it indoors or outside.
BADDY comes with an app that lets you define loop and random playing sequences. It runs for 90 minutes on battery and supports 9 strokes (including drops, drives). The robot has a max strokes frequency of 2 per second.