So far, I have found these robots:
- Mars exploration rover Spirit
- Mars exploration rover Opportunity
- Mars exploration rover Curiosity
I excluded the Huygens probe, the ETS-VII satellite and the Sojourner rover, as their capabilities are unclear to me. This paper claims the Sojourner rover "exhibited only rudimentary autonomy" and had "unused capability for autonomously avoiding obstacles in its path." The difficulty is in finding information detailed enough to determine whether these robots were truly autonomous.