At Swift, we've been crafting both single and dual beam gates for decades. Interestingly, we resisted offering single beam gates for about 20 years due to my strong belief in what some might call ‘first principles’. The concept of using a software filter to negate false triggers—caused by an arm or hand breaking a single beam—didn't sit well with me. We only started selling both versions because we had initially developed a single beam device strictly for ground use, which we later adapted to a budget-friendly, software-corrected gate. This single beam technology was derived from our older Speedstart device, introduced in the early 2000s. This innovative device, the brainchild of my old friend John Pryor—a luminary in rugby strength and conditioning—gained widespread adoption by top coaches like Dean Benton, Nic Gill, and others in rugby. It revolutionized timing by starting the clock with the lifting of a foot, a topic I'll explore more in a future article.
Now, back to the crux: Single vs. Dual beams. Dual beam gates wait for both the top and bottom beams to be obstructed before recording a time, a process we term as an "AND" function. In simpler terms, “Top AND Bottom” beams must be blocked to create a split time. This mechanism is highly specific and virtually foolproof, targeting the torso, the closest point to an athlete's center of gravity achievable with this tech.
In contrast, single beam gates can trigger from multiple body parts—arms, hands, torso, thighs, shins; essentially, any part that crosses the beam. You might wonder how we manage to correct these variances. Rob Newton, even before earning his PhD, was the pioneer of this approach, now widely embraced. The strategy involves assuming the torso as the widest part of the body, selecting the leading edge of the widest pulse as the split trigger. While generally effective, this method is not without its faults—imagine a beam triggered horizontally by a knee or elbow. Variations in athlete height could result in a knee or elbow registering the time, which also typically shows slightly faster times due to the nature of the correction. Understanding these nuances is crucial as it underscores that the choice of timing technology significantly impacts the data accuracy, and comparing results from these differing methods isn't recommended.
In conclusion, whether choosing single or dual beam gates, one must consider their distinct operational dynamics and the potential impacts on timing accuracy, making an informed choice critical to achieving reliable and consistent athletic performance measurements.