Unmanned Systems Technology 004 | Delair-Tech DT18 | Autopilots | Rotron RT600 | Unmanned surface vehicles | AMRC | Motion control | Batteries

66 A utomated, autonomous and remotely operated vehicles need precise, accurate control of linear, angular and rotary motion for propulsion and manoeuvring, pointing of sensors and the management of weapons, manipulators and other tools, often in harsh conditions. Conceptually, there are two motion control domains: an internal one concerned with the machine’s moving parts, and an external one concerned with positioning the vehicle in and navigating it around its environment. While the core sensor technologies are fairly mature in both domains, there are still innovations in the pipeline. Asked to characterise the market, industry people tend to use phrases such as “dynamically expanded” and “sheer size” – what was a highly esoteric and specialised technology a decade ago has become a consumer commodity, one of them said. The market is expected to grow a lot further still as unmanned platforms take on more tasks that once needed constant human intervention. In the external domain, sensors such as GPS, radar, electro-optical cameras and Lidar are either mature or approaching maturity, and high-volume applications in the automotive industry for example are bringing down the costs for unmanned systems. In the internal domain, industrial, aerospace and defence, scientific, domestic and hobby applications have produced many sensors capable of feeding back rotational speed, position, torque, temperature, humidity and any number of other parameters to computerised control systems, particularly those based on servos. For automated motion control, the servo is king. Demand for servos in unmanned vehicles continues to grow in all kinds of applications and, because these humble yet vital devices constitute an enabling technology for every type of automated machinery, it is worth looking at some of the key principles behind them. Peter Donaldson explains the technology behind motion control systems, and offers some pointers to future developments Autumn 2015 | Unmanned Systems Technology Clear directions