The model of a vibro-impact capsule system is studied in this paper to provide a fundamental understanding of its dynamics for potential medical and engineering applications. The system consists of a capsule having a main body which interacts with an internal mass driven by a harmonic excitation. Impacts occur when the internal mass contacts a weightless plate connected to the capsule main body. The main function of the system is to drive the capsule by overcoming resistance forces from the environment. Our bifurcation studies show that the dynamic behaviour of the system is mainly periodic, and the best progression can be determined through this analysis by a careful choice of the system parameters. Energy consumption is also considered and it is found that the parameters for the best progression and for the minimum energy consumption are different, and therefore, a trade-off between the best progression and the energy consumption is required to optimize the system behaviour.