As part of the Starbug development, a range of actuator technologies have been prototyped and trialled in the quest to develop this novel focal plane positioning system. The Starbug concept is a robotic positioning system that deploys multiple payloads, such as pickoff optics, optical fibres and other possible devices to micron level accuracy over a flat or curved focal plane. The development is aimed at addressing some of the limitations of other positioning systems to provide a reliable, cost effective way of positioning multiple payloads in ambient and cryogenic environments. In this paper we identify the specification and required characteristics of the micro-robotic actuators as applied to the MOMSI instrument concept, present descriptions of some of the prototypes along with the results from characterisation and performance tests. These tests were undertaken at various orientations and temperatures as well as using different actuator concepts.