  Leak detection and water quality monitoring are requirements and challenging
tasks in Water Distribution Systems (WDS). In-line robots are designed for this
aim. In our previous work, we designed an in-pipe robot [1]. In this research,
we present the design of the central processor, characterize and control the
robot based on the condition of operation in a highly pressurized environment
of pipelines with the presence of high-speed flow. To this aim, an extreme
operation condition is simulated with computational fluid dynamics (CFD) and
the spring mechanism is characterized to ensure sufficient stabilizing force
during operation based on the extreme operating condition. Also, an end-to-end
method is suggested for power considerations for our robot that calculates
minimum battery capacity and operation duration in the extreme operating
condition. Finally, we design a novel LQR-PID based controller based on the
system auxiliary matrices that retain the robot stability inside the pipeline
against disturbances and uncertainties during operation. The ADAMS-MATLAB
co-simulation of the robot-controller shows the rotational velocity with -4
degree/sec and +3 degree/sec margin around x, y, and z axes while the system
tracks different desired velocities in pipelines (i.e. 0.12m/s, 0.17m/s, and
0.35m/s). Also, experimental results for four iterations in a 14-inch diameter
PVC pipe show that the controller brings initial values of stabilizing states
to zero and oscillate around it with a margin of 2 degrees and the system
tracks desired velocities of 0.1m/s, 0.2m/s, 0.3m/s, and 0.35m/s in which makes
the robot dexterous in uncertain and highly disturbed the environment of
pipelines during operation.
