Swarm Robotics (SR) is a relatively new field, inspired by the collective intelligence of social insects. It involves using local rules to control and coordinate large groups (swarms) of relatively simple physical robots. Important tasks that robot swarms can handle include demining, search, rescue, and cleaning up toxic spills. Over the past decade, the research effort in the field of swarm robotics has intensified significantly in terms of hardware, software, and systems integrated de- velopments, yet challenges still exist; particularly concerning standardization, scalability, and affordable deployment. To con- textualize the state of swarm robotics technologies, this paper provides a systematic literature review (SLR) of swarm robotic technologies published from 2014 to 2024, with an emphasis on how hardware and software subsystems have co-evolved. We contribute an overview of 40 studies in peer-reviewed journals along with a well-defined and replicable systematic review protocol. The protocol describes criteria for including and excluding studies; and outlines a data extraction approach. We explored trends in sensor hardware, actuation methods, communication devices, energy systems, as well as an examina- tion of software platforms to produce swarm behavior, covering meta-heuristic algorithms and generic middleware platforms such as ROS. Our results demonstrate how dependent hardware and software are to achieve swarm intelligence, the lack of uniform standards for their design, and the pragmatic limits which hinder scalability and deployment. We conclude by noting ongoing challenges and proposing future directions for developing interoperable, energy-efficient swarm robotics (SR) systems incorporating machine learning (ML).