Roadheader is an engineering robot widely used in underground engineering and
mining industry. Interactive dynamics simulation of roadheader is a fundamental
problem in unmanned excavation and virtual reality training. However, current
research is only based on traditional animation techniques or commercial game
engines. There are few studies that apply real-time physical simulation of
computer graphics to the field of roadheader robot. This paper aims to present
an interactive physically-based simulation system of roadheader robot. To this
end, an improved multibody simulation method based on generalized coordinates
is proposed. First, our simulation method describes robot dynamics based on
generalized coordinates. Compared to state-of-the-art methods, our method is
more stable and accurate. Numerical simulation results showed that our method
has significantly less error than the game engine in the same number of
iterations. Second, we adopt the symplectic Euler integrator instead of the
conventional fourth-order Runge-Kutta (RK4) method for dynamics iteration.
Compared with other integrators, our method is more stable in energy drift
during long-term simulation. The test results showed that our system achieved
real-time interaction performance of 60 frames per second (fps). Furthermore,
we propose a model format for geometric and robotics modeling of roadheaders to
implement the system. Our interactive simulation system of roadheader meets the
requirements of interactivity, accuracy and stability