In light of technological advancements, the mining industry is seeing an increase in equipment automation. A hydraulic rockbreaker is a machine that would benefit from automation. The goal of this research is to develop some of the necessary algorithms to render a rockbreaker semi-autonomous. Semi-automation of such systems would allow for improved ease of use, increased productivity and efficiency of rock breaking operations, reduced maintenance costs while also removing the operator from harm's way. Several components are necessary to make semi-automation feasible, including a dynamic model as well as trajectory planning algorithms which generate collision-free trajectories to be used by a controller. The development of a complete dynamic model for such a system would allow for better control when using model-based controllers. However, such a model is difficult to develop in practice, has added complexity and may be computationally expensive. In this work, simplified dynamic models are developed and compared with respect to a complete dynamic model of the rockbreaker. One of the resulting simplified dynamic models, which only considers the inertial and gravitational effects of the rockbreaker's mechanical links as well as the gravitational effects of its hydraulic actuators, is shown to provide adequate representation of the system so as to be used in a model-based controller. The work also develops a set of offline trajectory planning algorithms that generate time-optimal trajectories which ensure smooth motions and hydraulic valve actuation while satisfying the system's flow rate constraints. With the addition of a collision avoidance strategy and collision detection algorithm, the generated trajectories within the system's work environment can be expected to be collision-free.
Keywords:
Rockbreaker; Hydraulic Machinery; Automation; Dynamic Modeling; Trajectory Planning; Collision Avoidance; Collision Detection