Spray paint monitoring and control using doppler radar techniques

A spray paint monitoring method for optimizing the application of sprayed paint onto an object that is to be painted, said spray paint monitoring method comprising the steps of:

• spraying paint particles toward an object that is to be painted using a paint spray gun;
• radiating Doppler radar signals at the paint particles that are moving toward the object;
• receiving backscattered Doppler shifted radar returns from the moving paint particles;
• processing the received backscattered Doppler shifted radar returns to produce data indicative of the velocity of the paint particles;
• and
• displaying the data indicative of the velocity of the paint particles.

A system for applying paint onto an object that is to be painted, said system comprising:

• a spray painting system comprising a pressurized spray gun adapted to spray paint at an object that is to be painted;
• a Doppler radar comprising:
• a transmitter that includes a CW signal source coupled by way of a power divider to a power amplifier;
• a transmit antenna coupled to the power amplifier;
• a receiver comprising an RF preamplifier and a mixer, and wherein the mixer derives its local oscillator signal from the CW signal source of the transmitter;
• and
• a receive antenna coupled to the RF preamplifier;
• and
• a signal analyzer coupled to an output of the mixer and coupled to the spray painting system, for analyzing the Doppler return signals and displaying data indicative of the velocity of the paint particles, and for generating a control signal that is coupled to the spray gun to control the pressure at which the paint is ejected therefrom.

A method for applying paint onto an object that is to be painted, said method comprising the steps of:

• spraying paint particles toward an object that is to be painted at a predetermined pressure;
• radiating Doppler radar signals at the paint particles that are moving toward the object;
• receiving backscattered Doppler shifted radar returns from the moving paint particles;
• processing the received backscattered Doppler shifted radar returns to produce data indicative of the velocity of the paint particles;
• displaying the data indicative of the velocity of the paint particles;
• and
• generating a control signal from the data and applying it to control the pressure at which the paint is sprayed and thereby optimize the application of sprayed paint onto the object.