Fully-autonomous, robotic vehicles that excavate, grade, load, unload and drive across construction sites without direct human interaction are an ambitious dream for the future. However, closer within reach are equipment control systems called “semi-autonomous tele-operations.”
There are two varieties of semi-autonomous tele-operations: in-sight and remote.
In-sight tele-operations are those where the operator is outside of the machine itself, performing and visually overseeing functions using a remote control. Although some of these might be pre-programmed, the key is that a human is nearby and in sight.
The construction industry is already seeing the introduction of basic in-sight tele-operations from several leading manufacturers. These control innovations are not restricted to just large vehicles. For example, Bobcat will soon release a proprietary, in-sight, remote-control system called MaxControl for the company’s line of compact loaders, allowing operational control using a mobile device as far away as 300 feet.
Remote tele-operations, however, are much more complex. The operator is in a control room removed from the immediate work area. The machine’s functions are still controlled using remote control — usually a joystick — however human supervision is achieved through audio-visual feedback provided by a wireless link.
Marlex Engineering in Ancaster, Ont., is a leading research and development software developer specializing in personal detection systems that alert both workers and operators when personnel are dangerously close to mobile equipment.
Company president Uwe Schaible explains that leadership in autonomous equipment operations comes from the mining industry, motivated by its desire to improve efficiency and safety. For example, he says, “In smelter operations, you have to haul hot slag out of a smelter using large vehicles. If you had a driver inside the cab, they would be subjected to heat, gases and other dangers.”
While construction shares the same concern for safety and efficiency, mining has a distinct advantage in terms of the practical application of advanced semi-autonomous control systems. Mining is able to keep humans away from certain sensitive zones entirely, unlike general construction. Further, mining operations are established for long periods — 20 years or more — whereas construction sites have comparatively short lifespans. Given the investment required to build highly sophisticated, automated processes, return-on-investment calculations differ. As a result, the widespread adoption of remote tele-operations in construction in a meaningful way is further away.
There are technical challenges as well. One challenge that Schaible identifies concerns the feedback transmitted to operators out of visual range. They need to feel part of the machine in order to work effectively and efficiently.
“That capability is already there in the entertainment industry with things like motion gaming and race car simulators — you can be immersed in it and feel that you’re actually inside the vehicle. But again, when it comes right down to it, it’s about cost.”
Linked to the feedback challenge is image stabilization. The vehicle is bouncing around and vibrating. Without a high level of image stabilization, the remote operator could get dizzy and disoriented.
The issue of high-quality, visual feedback draws attention to yet another challenge — the “latency” (speed of the data transmission) of the wireless system linking the machine to the remote operator.
Remote operators require visual feedback that is measured in micro-seconds. The advent of 5G networks may provide some relief in the future, however, the security and integrity of the wireless signal will likely require a proprietary, site-specific system, not one provided by standard mainstream providers.
Schaible is realistic about the current state of remote tele-operations in construction. “There’s a lot of value to taking a human out of the machine — safety, training, repeatability. However, you have to choose the low-hanging fruit of your application.”
When foreseeing the possibilities for construction in the future, Schaible strikes a more optimistic tone.
“I think the solutions are out there, but just a little bit in further time right now.”
John Bleasby is a Coldwater, Ont. based freelance writer. Send comments and Inside Innovation column ideas to firstname.lastname@example.org.