I shot some footage with someone dressed in a robot costume and needless to say, despite their efforts, their movement looks very "unrobot-like". I was thinking I would just remove some frames between key movement positions but I was hoping there might be a way I can tailor the footage in After Effects to make the robot a little more rigid. I'm still quite new to After Effects so any suggestions?
Effect>time>posterize time, set to a low frame rate?
Or yes, you could use Time Remapping, with hold keyframes at the ends of each movement. Look for tutorials on it, but keep this in mind: the value of the time remapping effect at any given time is the frame of video currently being displayed. So, if you're looking at the time remapping graph, a flat plateau indicates a freeze-frame, because the value (displayed frame) is not changing. A slope up and to the right indicates forward playback, and down to the right indicates reversed playback.
Be prepared for a lot of experimentation here until you get it right. If you need to start over, just delete time remapping from the layer and start over by applying it again.
Time remapping can be tricky if you are new to after effects and take a long time to get just right. Also that is a good way to ease motion and for a robot you don't really want that. I would just freeze for a a few frames at the end of each move he makes. Or if you really want to practice animation, find a good frame to freeze and roto all of his limbs and animate him yourself.