Interesting piece. Mechanical is hard to get wrong, but to me the pose looks a bit odd. Perhaps a different, more distinctive angle would help. In Photoshop, try turning it into a silhouette but adding the fill filer all black then see if someone can make out what it might be. if they cant, then I'd suggest making it at an angle and pose than can be easily recognizable even if all blacked out. That tends to help your work become more dynamic and its another typical practice with artists in class. silhouettes are important for helping to develop overall form of a figure.
Rating of 4/5 - 8/10