iv been doing judo for a couple months now and want to start practicing different arm locks, chokes, submissions. i want to practice at home but i have nobody to practice with. i only have sisters and they don't want me to do that on them :P so i want to know if there's some type of bar you can buy that is a simulation of arm and leg joints so that i can practice with it... or any thing i can buy for at home with not alot of space and can use alone. any dvds too would help.