I've had orgasms, prostate- and anally-centered, from using Aneros or other hands-free prostate massager, from dildos of almost any kind (glass wands, some for g-spot stimulation; realistic dildos; non-realistic dildos) where I'm using my hand to thrust it in and out of me in different positions, and from riding dildos that can be ridden like realistic silicone dildos that have a base that can be stable on the floor or in a dock of some sort.
I never touch my cock when I'm trying to have orgasms from these methods. In fact most times if I do touch my cock it sort of alters the stimulation inside me and I don't have an orgasm. I can blend them and have a Super T orgasm while I have something in me and while stimulating my erection; usually I just have an Aneros toy in me and I get hard and make myself cum traditionally while the toy is in me, it is very powerful!
There are some ways and methods to achieve what you are seeking. I tried to have hands-free prostate/anal orgasms for 10 years before I finally had one. I was distracting myself with porn and had a different mindset and idea of what the "end goal" was supposed to be. Once I gave into it and removed distractions I started having dozens of orgasms each session. That was 11 years ago and my orgasmic potential increases each year.