Issue 39 Unmanned Systems Technology August/September 2021 Maritime Robotics Mariner l Simulation tools focus l MRS MR-10 and MR-20 l UAVs insight l HFE International GenPod l Exotec Skypod l Autopilots focus l Aquaai Mazu

76 “After those, the really important figure is how many ‘lines per hour’ the client wants, which is an important bit of jargon for gauging throughput in warehouses,” Lueg explains. “Say you’re buying from Amazon two shirts of the same line and one pair of trousers: that’s two lines and three items. Traditionally a picker goes to the correct rack for each line, and it’s assumed they’ll take the same amount of time per line to pick. So, in this case we pick two lines. “If someone buys two identical pairs of socks and one shirt though, that’s still two lines because taking a few seconds to retrieve a second pair of socks from the shelf where they’re all kept doesn’t really matter. Either way, 99% of the work is in walking to and from each rack, so a human picker can do maybe 80-100 lines per hour at most when working entirely manually. “In our warehouses, however, the pickers stand still at what we call pick stations, and the Skypods will bring the orders to them – each picker processes 400-500 lines per hour this way. That’s where the client gets the bulk of their ROI from our system – we can potentially give them a fivefold increase in lines per hour.” It is therefore critical that Exotec has the necessary information for its planning mathematics: the rates of orders, items and lines are key to determining how many robots are needed to fulfil the anticipated throughput of each warehouse. Combining this figure with internal space information enables the team to derive the correct dimensions of both the robots and the various bits of static infrastructure for picking, battery charging and so on. Afterwards, the robots and additional equipment can be shipped by container vessel for assembly at the warehouse. The largest infrastructural parts are the racks themselves. Exotec has sourced rack suppliers in Europe and North America to make it easier to transport them. While worker stations, Skypods and software are usually installed on-site by one or two Exotec field engineers (or engineers from an Exotec distribution partner), the rack suppliers traditionally build the racks at the warehouse site personally to ensure no mistakes are made, as a centimetre-level inaccuracy could prevent a robot from climbing and accessing a significant portion of stock. “We invested in that supplier to make sure they had the necessary production line for our unique racks,” Lueg says. “We knew exactly what our system needed, so we didn’t launch an open bid for making them, and having domestic suppliers is key because you can’t be shipping massive quantities of sheet metal between America and Europe – our costs would jump hugely.” On the warehouse floor As Lueg points out, “The Skypod is effectively the only moving part in Exotec’s warehouse infrastructure, and the only part with wiring if you don’t count the computers and scanners at the various manned stations that form the rest of our system. That’s actually very important in warehouses from a fire suppression perspective – the more wiring there is, the more chances for sparks that can set huge quantities of stock ablaze.” A Skypod’s mission begins when it is called upon by ASTAR, Exotec’s warehouse control software (WCS), to August/September 2021 | Unmanned Systems Technology A Skypod hands off its cargo to a warehouse manager at a pick station