Radar Technology
Applied to Golf Performance

Doppler radar provides Zelocity™ Golf Performance Monitors the advantage of collecting hundreds of thousands of data points for ball flight and swing analysis. The radar “sees” the club and golf ball before, during, and after the moment of impact, and follows the ball as it flies down range. This allows Zelocity™ to collect a stream of actual data points (100,000 per second) from the Doppler radar signal; see the radar data stream table below.

This data is then processed through patented mathematical algorithms, to produce vital statistics about the shot, including club head speed, ball velocity, launch angle, ball spin, distance, and power transfer ratio.

• Club Head Speed is speed of the club head at impact, in miles per hour.
• Ball Velocity is speed of the ball after impact, in miles per hour.
• Launch Angle is the measured angle of flight from horizontal (ground or mat) in degrees.
• Ball Spin is total spin, in revolutions per minute (RPM)
  • No striping of the ball is required
• Carry Distance is the distance the ball flies in the air before hitting the ground.
• Total Distance is Carry Distance plus estimated roll for a PGA tour cut fairway.
• Power Transfer Ratio % is calculated as Ball Velocity / Club Speed x 100%. This represents an indication of centeredness of impact between the ball and club face. An exception to this rule is the thin or topped shot which may show a high ratio even though off-center impact was made.

Zelocity™ Golf Performance Monitors use Doppler radar, combined with patented mathematical algorithms, to accurately determine ball flight characteristics of interest to instructors, equipment makers, retailers, and players of every skill level.

RADAR (RAdio Detection And Ranging) measures the reflection time of microwave energy bounced off a target object, such as a golf ball or golf club.

The “Doppler Effect” is the apparent change in frequency caused by a change in distance between the transmitter and the target object during transmission/reception. For example, as a ball flies down range, the reflected frequency decreases relative to the transmitted frequency (i.e., the transmitted and reflected frequencies would be the same if the ball were not moving). Measuring this change, or “Doppler Shift,” allows the actual velocity of the ball to be determined.

Doppler radar is uniquely suited to the job of tracking club and ball flight.

Why? Robustness. Radar signals operate at extremely high frequencies and cover a large cross-section of space. They are unaffected by lighting and weather conditions. They are “always on,” so they don’t require expensive, high-maintenance shuttering mechanisms found in other types of monitors.

Zelocity™ monitors yield the equivalent of a radar “videotape” of the flight of the ball. The monitor tracks the ALL of the action of the club as well as the ball as it flies downrange. Competitive monitors take a limited number of snapshots of the ball (and thus are very sensitive to setup conditions) and then perform complex calculations to arrive at estimates of ball flight. The Zelocity™ difference is MEASURED results.

Accuracy

Rather than simply publish a set of accuracy statistics without backup or detail, Zelocity™ has defined and committed our company to a rigorous quality program to ensure our component materials, manufacturing processes, end products, distribution methods, and support systems all come together to deliver unparalleled satisfaction to our customers.

Our minimum guidelines for product performance are shown in the following table.

To meet these guidelines, our program includes frequent internal tests as well as product trials at independent testing facilities such as GolfLabs in San Diego, CA.

We collect and analyze performance data when developing new products and also for mature products, to ensure our methods consistently yield quality results.