The penalty for a felony conviction in the State of Washington will depend on:
1. The seriousness of the crime;
2. The number of prior felony convictions;
3. Whether there are "other current offenses";
4. If the State added an enhancement (deadly weapon, firearm, school zone, etc...); and
5. Whether there is a basis for seek an exceptional sentence.
For someone with no other criminal history, enhancements or exceptional sentence basis, he/she would be looking at a term of 31 to 41 months in prison for a Robbery in the First degree conviction. It is a Class A felony with a maximum sentence of life in prison and/or a $50,000 fine. Robbery-1 qualifies as a "strike offense" for the purposes of the Three Strikes and You're Out Law.
If the State filed a firearm enhancement, it will add 60 months on top of the sentence (it is more if the defendant has had a prior enhancement). There is no earned "good time" on enhancements.
If the person(s) he/she was with was armed and an accomplice, it will not matter that your friend was not armed during the robbery. In the eyes of the law, the accomplice is just as culpable as the principal.
May your friend have a speedy recovery. Please let me know if I can be of further assistance.