Work on GPS, Heads-Up Displays, Vision-Based Vehicle Speed Measurement

After years of very long hours and hard work, I was relieved when Vansco offered me the position of Chief Research Officer.  Vansco built me a lab in a quiet area of the plant, gave me resources and ideas, and asked me to play.

This only lasted a short time, as both my personal priorities and Vansco’s priorities changed, and within a year I was back in APT – although, no longer as General Manager, which was fine with me.

Global Positioning System

At our CEO Dave Sokol’s suggestion, I dove into GPS positioning, real-time kinematics (RTK corrections), and their potential use in agriculture.  I obtained some early GPS receivers and experimented with them.  At that time, they were very expensive!  I was amazed at their accuracy and reliability, even then.

Heads-Up Displays

I also toyed with heads-up displays.  We anticipated that this would be in demand in agricultural equipment soon.  I examined the existing state-of-the-art, and projected where we might take the technology.

Implement Velocity Measurement

One of the challenges in agriculture is the accurate measurement of ground speed.  This is required to accurately control seed and material application rates, and measure harvest efficiency.  Unlike road vehicles, you cannot just measure wheel rotation, because considerable slippage is seen all the time.  The state-of-the-art at that time was to use a RADAR sensor aimed at the ground at an angle, measuring the Doppler shift in the returned signal.  Taking into account the trigonometry of the angle, you can accurately measure velocity with respect to the ground.   However, on smooth surfaces, such as puddles and some roads, this system will experience almost-total reflection away, and no Doppler shift can be measured.

Our solution was to use a colour camera, watching the terrain below the vehicle.  By correlating the images in real-time, the 2-D displacement between the images can be estimated, and velocity can be accurately calculated.  I obtained a patent on this innovation.