  This paper concentrates on the development of Chat-PM, a class of composite
hybrid aerial/terrestrial manipulator, in concern with composite configuration
design, dynamics modeling, motion control and force estimation. Compared with
existing aerial or terrestrial mobile manipulators, Chat-PM demonstrates
advantages in terms of reachability, energy efficiency and manipulation
precision. To achieve precise manipulation in terrestrial mode, the dynamics is
analyzed with consideration of surface contact, based on which a cascaded
controller is designed with compensation for the interference force and torque
from the arm. Benefiting from the kinematic constraints caused by the surface
contact, the position deviation and the vehicle vibration are effectively
decreased, resulting in higher control precision of the end gripper. For
manipulation on surfaces with unknown inclination angles, the moving horizon
estimation (MHE) is exploited to obtain the precise estimations of force and
inclination angle, which are used in the control loop to compensate for the
effect of the unknown surface. Real-world experiments are performed to evaluate
the superiority of the developed manipulator and the proposed controllers.
