  The interception of moving targets is a widely studied issue. In this paper,
we propose an algorithm of intercepting the moving target with a wheeled mobile
robot in a dynamic environment. We first predict the future position of the
target through polynomial fitting. The algorithm then generates an interception
trajectory with path and speed decoupling. We use Hybrid A* search to plan a
path and optimize it via gradient decent method. To avoid the dynamic obstacles
in the environment, we introduce ST graph for speed planning. The speed curve
is represented by piecewise B\'ezier curves for further optimization. Compared
with other interception algorithms, we consider a dynamic environment and plan
a safety trajectory which satisfies the kinematic characteristics of the
wheeled robot while ensuring the accuracy of interception. Simulation
illustrates that the algorithm successfully achieves the interception tasks and
has high computational efficiency.
