A sensor-fitted connected office desk developed by Arup engineers aims to give individuals greater control over their open-plan office environment.
Developed in response to surveys indicating the dissatisfaction of workers in open plan offices where the environmental and climatic conditions are centrally dictated by the building management system, the desk could allow every single worker to co-manage his or her immediate environment.
In addition to that, its intelligent sensors could enable considerable energy savings by automatically detecting whether someone is actually sitting at the desk and, if not, switching off monitors, lights or chilled beams as soon as the occupant leaves.
“The purpose of the desk is to give back control to the people and allow them to influence their work environment,” explained Michael Trousdell, Mechanical Associate at Arup. “The light level is easily done, adjusting the lights locally on the desk, but to influence temperature, you need to influence the chilled beam or some fan coil unit, which can be more complicated because in the office space they are going to be controlled by a building management system.”
The Arup team has therefore developed software that replaces the central air-conditioning unit controller and allows people working at the smart desk to locally control the temperature.
Each user can set his or her preferred temperature and the system either calculates the mean value or adjusts the temperature based on who is present at every given moment.
“We have sensors logging temperature, relative humidity, the light level and other variables that provide input to the smart software,” said Trousdell.
“Most building management systems only monitor air temperature, but that’s only one parameter that influences comfort. Sometimes you have 25 degrees and you still feel cold because it is very draughty. But if you can monitor air movement and humidity, you can provide much better control.”
The desk also automatically controls lights and adjusts the light colour and intensity based on the time of the day, as well as the season, to resonate with natural human biorhythms to boost productivity.
Individual elements of the system draw electricity from a DC power unit via Ethernet cables. The researchers say this set-up not only allows the use of extremely low voltages, but also enables easy control over every single element.
“The system that we have here allows much more granular control, so instead of just having the power on all the time, we can use a passive infrared sensor or some other mechanism for detecting occupancy,” Trousdell explained.
“When someone is away from their desk, the system can detect that and respond by switching off the monitor. That’s possible because with this power over Ethernet infrastructure, you can digitally switch it on and off at the switch, which with an AC system would be much more complicated.”
There are four Ethernet cables powering the light, the monitor, laptop charger and the smart sensors.
The modular desk itself has been designed by the Arup team to elegantly provide room for every component. The team said the cost of such a custom-made desk is actually lower than that of an average commercially produced office desk.
“We were able to design a desk with features that we wanted in 3D,” said Trousdell. "Once we were happy with the design, we sent the digital file to a small company who cut the pieces out of plywood and sent them back to us. Each desk is made as a kit and has little wheels at the bottom so that we can easily move it around.”