At this year’s IAAF World Athletics Championships, we saw the pinnacle of the athletic calendar take place in London earlier this month. Millions of viewers around the world tuned in to see the stars Mo Farah and Usain Bolt’s final races, which didn’t actually go to plan. However the picture everyone at home was watching did perform. Here, Graham Mackrell, Managing Director of precision gearing specialist Harmonic Drive, talks us through the gearing requirements that were in place for the broadcast cameras.
Harmonic Drive Gears, otherwise known as strain wave gears, were used at the World Athletics Championships in television camera rigs. These gears are used due to their distinct features that put them at the pinnacle of gear engineering and make them suitable for the challenges of broadcasting.
Remote controlled cameras, used on rigs, are being increasingly used by camera operatives to capture shots from hard to reach angles or to allow the camera to zip across the track on wires. This is stable, much quicker than a human could film and also solves any security or safety concerns with a camera person high up in a stadium.
To maintain smoothness when filming, harmonic drive gears have zero backlash for their entire operating life. This is achieved by naturally pre-loading the Flexspline into the Circular Spline and ensures that the filming is smooth and without any noticeable stuttering or bumps.
Low backlash is achieved by other gearing methods by tight gear engagement, however this can cause wear on the gear, torque ripple and an increase in noise, which would obviously be unacceptable for a camera capturing video.
There are of course other considerations than motion. Harmonic Drive Gears are extremely accurate, to provide high positioning accuracy for camera pans and tilts, and boast a compact, lightweight design to ensure safety when manoeuvring across the stadium on wires.
As the elite of the world’s athletes visited London to take part in the World’s Athletics Championships, it was only fair that the elite of the world’s engineering feats were on hand to support the event. So, just think as you were cheering on Usain Bolt final race or Mo Farah’s stamina that saw him take the silver, think of the hardworking gears that were powering your viewing of the event.