Uchi Komi with a bicycle inner tube.
Take a bicycle tire inner tube , and slice it so that you essentially have a long strip of rubber that you can wrap around the tree, and hold the ends in your hands.
Approximate your preferred grip's hand positioning (lapel and cuff, double lapel, etc), and practice entering as if you were performing specific throws, whilst pulling in the appropriate manner on the inner tube.
Tie your Gi belt at about waist height around a pillar/post/tree of your choice. If it slips down, a bit of duct tape will do to either hold the belt in place, or replace it for the task.
Make sure that your belt is at the correct height in relation to your opponent's (the belt/tape around the tree/post/pillar), and that your weight is distributed correctly. Think about kuzushi as you pull on the arms. Think about your foot placement, positioning, and agility.
Can be done as static Uchikomi, or to breakdown an aspect of the technique.
Obviously not a replacement for actual uchikomi or training with a partner, but a good drill nonetheless.
An introduction to using bicycle innertubes to practice judo techniques, develop form, and build strength.
This is an old video of a Judoka training by using an old bicycle inner tube.
