The Semi-Automated Inspection Cart
The semi-automated inspection cart was developed to produce
evenly-spaced, repeatable taps on a part surface. The inspector grips
the cart in a manner similar to a computer mouse and pushes the cart
along the surface of the component being inspected. The cart is pushed
along a series of straight lines on a template attached to the surface
of the component. Data is feed into the computer with each tap produced
by the cart until the end of a line has been reached. At the end of
a line, the operator picks up the cart and moves it to the next line.
A button is clicked on the front of the cart to inform the computer
that the operator is ready to scan the next line. This is repeated until
the entire area has been tapped.
The device uses magnets to both raise the tap probe and
to assist it in its motion toward the surface. Figure 1 below shows
the tap probe being raised by magnets. (Note that the like poles of
the magnet are opposing each other.) The raising process continues until
the travel of the probe is physically stopped (Figure 2). As the rotating
magnet passes by the constrained magnet, the direction of the force
acting on the probe is reversed and the probe is thrown
down (Figure 3). The instrumented probe then impacts the surface, creating
a tap (Figure 4) and the impact time is measured. The cycle then repeats
itself when a different magnet on the rotating wheel raises the probe.
(Only one magnet is shown on the wheel.)