Film-making gears up for control

A wider cultural shift in our viewing habits, the result of the increased competition from digital and online content, means that viewers, more connected to the tablet than the TV, have begun to demand more interactive content, preferring to tweet and comment whilst watching.

The advent of services like YouTube Live have catalysed this growth, with viewers able to simultaneously post questions to live shows, whilst actively commenting on, and discussing, their thoughts with millions of likeminded individuals. The combined effect on the broadcast industry is a demand for more and better content, produced on lower and lower budgets.

Traditionally, camera operation has been a manually intensive process, with camera operators having to use fine movement to create controlled camera movements, which can then be replicated for multiple takes.

The rise of artistic filmmaking, the increased use of computer generated imagery (CGI) and the popularity of high definition (HD) and 3D movies as well as many other special effects used in modern cinema would simply not be possible using traditional filming techniques. This is where motion control takes over.

Pre-programmed moves

Typically consisting of a camera rig mounted on a motorised robotic arm, motion control allows pre-programmed moves to be entered into the camera control software. Highly accurate movements can be made, which would otherwise be impossible even with a cameraman's steady hands; and these moves can be repeated again and again with pixel-perfect precision. Post production then allows multiple clips to be composited together to create a final scene.

With this new-found accuracy and repeatability, filmmakers can clone characters, replicate crowds of people and mix camera array setups with motion control footage to create scenes – such as the iconic frozen-moment bullets scene from The Matrix.

Scaled moves are another technique achieved with motion control. By filming a highly detailed model of a prop or set, and then magnifying the movement by a given ratio, filmmakers have been able to realise the tall spires of Hogwarts' fictitious castle in Harry Potter and the diminutive height of hobbits and dwarfs in The Lord of the Rings trilogy.

CGI has been taken to a whole new level with motion control. Because X, Y and Z axes of the the camera rig can be pre-programmed, data can be imported to and from the CGI software, allowing pre-production control over camera angles and specific controlled moves.

Harmonic Drives supports filmmakers by developing reliable equipment with the ability to take a beating in the often harsh conditions in which it is used. A good example of this is in the BBC's recent Frozen Planet series. Compact servo actuators provide the gearing for a pan and tilt camera, which was used to film a six month time-lapse in the Arctic. With rugged Viton seals, maintenance free lubrication and improved corrosion protection, the equipment was able to withstand the ferocious winds and bitterly cold, sub-zero temperatures.

As TV programmers seek to commission content with a higher production quality, on a lower budget, the demand for portable equipment has increased. Products have been adaptd to maintain performance in a smaller package: hollow shaft actuators are lightweight and compact, with smooth torque and high torsional stiffness; backlash-free gearing offers precision motion control, resulting in excellent accuracy and repeatability; digital controllers complete the package, allowing setup software to run in Windows.