Swarm robotics is a very emerging field of research that studies the collective behaviour of multi-robot systems. It is based on applying various methodologies to a group of several robots to perform tasks unreachable to individual robots. Due to the flexibility of Swarm Intelligence algorithms, Optimization techniques are suitable to be implemented in robotic swarms to deal with real-world complex multi-disciplinary problems. This paper explores various swarm optimization algorithms for robotic swarms like PSO, GPSO, CSO, ACO and GSO. An in-depth survey is presented for all the said algorithms and the projected future of swarm optimization is discussed