So you have to destroy all the robots to go to the next level. But you can't harm the robots directly: only friendly fire can destroy them.
So try to go in the middle and dodge when they fire. If only one robot is left, jump to your death, you need to restart the level. Also note that they have a tendency to synchronize their firing which can help you.
Also note that the later levels are very hard so don't feel bad if you can't beat the game (11 levels total).
W,A,S,D for moving, SPACEBAR for jumping