  In this paper, we address the Perception--Constrained Model Predictive
Control (PCMPC) and state estimation problems for quadrotors with cable
suspended payloads using a single camera and Inertial Measurement Unit (IMU).
We design a receding--horizon control strategy for cable suspended payloads
directly formulated on the system manifold configuration space SE(3)xS^2. The
approach considers the system dynamics, actuator limits and the camera's Field
Of View (FOV) constraint to guarantee the payload's visibility during motion.
The monocular camera, IMU, and vehicle's motor speeds are combined to provide
estimation of the vehicle's states in 3D space, the payload's states, the
cable's direction and velocity. The proposed control and state estimation
solution runs in real-time at 500 Hz on a small quadrotor equipped with a
limited computational unit. The approach is validated through experimental
results considering a cable suspended payload trajectory tracking problem at
different speeds.
