useful tool

I often see useful tools for elder people in S.F. (I don't know the name though) I found  it's really useful because it not only helps elder people to walk, but it also could be a grocery bag and a chair. How awesome! I don't remember how was it in Tokyo but I think in general elder people who has a pain or any kind of problem in his/her leg usually cannot go out by themselves. I hope they can walk around without any hesitation.