  Aerial Manipulator Systems (AMS) have garnered significant interest for their
utility in aerial operations. Nonetheless, challenges related to the
manipulator's limited stiffness and the coupling disturbance with manipulator
movement persist. This paper introduces the Aerial Tendon-Driven Manipulator
(ATDM), an innovative AMS that integrates a hexrotor Unmanned Aerial Vehicle
(UAV) with a 4-degree-of-freedom (4-DOF) anthropomorphic tendon-driven
manipulator. The design of the manipulator is anatomically inspired, emulating
the human arm anatomy from the shoulder joint downward. To enhance the
structural integrity and performance, finite element topology optimization and
lattice optimization are employed on the links to replicate the radially graded
structure characteristic of bone, this approach effectively reduces weight and
inertia while simultaneously maximizing stiffness. A novel tensioning mechanism
with adjustable tension is introduced to address cable relaxation, and a
Tension-amplification tendon mechanism is implemented to increase the
manipulator's overall stiffness and output. The paper presents a kinematic
model based on virtual coupled joints, a comprehensive workspace analysis, and
detailed calculations of output torques and stiffness for individual arm
joints.
  The prototype arm has a total weight of 2.7 kg, with the end effector
contributing only 0.818 kg. By positioning all actuators at the base, coupling
disturbance are minimized. The paper includes a detailed mechanical design and
validates the system's performance through semi-physical multi-body dynamics
simulations, confirming the efficacy of the proposed design.
