Robot marks suspicious air cargo thanks to 3D vision sensor Visionary-S and vision integrator Wu XI Fu Jiang from China.
When air freight loses its boarding pass
Air freight plays a decisive role in the e-commerce business, which is why efficient handling of freight is a must. At Chang Sha Airport in China, plants have recently been put into operation which allow suspicious freight singled out by customs officers to be marked automatically by a robot so that it loses its boarding pass for the time being and can be ejected from the normal material flow downstream for further investigation. To give the robot the accurate data of where to apply the mark ideally, Visionary-S CX from SICK delivers precise three-dimensional geometric data.
Robot labels suspicious freight
International air freight traffic is dealing with quite some challenges – that’s why the process flows of freight terminals at airports need to be very efficient. At Chang Sha Airport in the Chinese region of China Hu Nan, customs authorities are currently revolutionizing the logistical handling of suspicious freight with the aid of a robot solution in which shipments that have to undergo a second check following initial inspection are marked fully automatically. So that the material flow system between the customs area and airfield knows which shipments have lost their boarding pass, a robot unit applies a label in a completely automated way. However, to be able to do this, the robot kinematics must know where the label should be applied from a three-dimensional perspective.
During the process, the label must be attached to the packaging with enough pressure, but not too much so as to avoid damaging the freight. Things are made even more complicated by the fact that neither the formats nor the packaging material are standardized in any way. Every single shipment therefore has to be measured three-dimensionally prior to being labeled in order to calculate a target coordinate for the robot. Limiting the travel path of the robot arm using a defined torque is not possible in this application due to the different material properties of cardboard packaging, paper envelopes and padded plastic pouches.
Structured light-powered stereovision provides a better view
The robot unit featuring Visionary-S uses a new solution from SICK as its eyes. The 3D vision camera combines the stereo vision principle with structured illumination. The compact device with enclosure rating IP67 delivers color depth images in real time with its three cameras arranged horizontally in a staggered manner. The structured illumination allows uniform structures to be measured as well. Single-color, uniform surfaces are usually difficult to analyze. Fans of photography will be aware of the problem when a camera’s auto focus admits defeat in front of a light or dark wall – at least until the AF assist light, which is also structured, is switched on.
The structured illumination of Visionary-S gives the viewing range its own surface structure, thereby generating image scenes that can be reliably measured. The ability to do this is particularly crucial in freight operations because uniform surfaces are the norm rather than an exception due to the consistent structure of cardboard packaging. Thanks to the integrated IR illumination, Visionary-S works both in total darkness and in strong daylight with an intensity of 40 klx. When it comes to resolution, the system delivers 640 x 512 pixels and takes 30 color and depth images per second, each of which contains more than 320,000 distance and color intensity values.
An expert at handling cargo
The Visionary-S is optimized for working ranges of 0.5 to 2.5 meters, making the camera ideal for handling baggage. In this way, the new automation solution for the Chinese customs authorities at Chang Sha Airport also represents the start of a new era in terms of efficiency when processing cargo. The system was developed as part of a collaborative project between system integrator Fu Jiang and SICK’s Chinese sales company with technical support from the company’s headquarters in Waldkirch. “The precise RGB- and depth information of the 3D camera could be easily adapted and integrated to suit our requirements thanks to the easy-to-use Application-Programming-Interface,” concludes Mr. Pan from Wu Xi Fu Jiang. The rugged construction of the robot unit for marking suspicious air freight today forms the basis of the 24/7 service required at airports. In view of international trade markets and the growing presence of online sales platforms, the high level of availability is necessary now more than ever, especially in Southeast Asia – independently of how fast the transport belts ultimately move in the handling area.
Summary: Changing the game in the logistical handling of air freight
Customs authorities greatly increased the efficiency in the process of ensuring that no freight defined by customs officers as suspicious cargo gets on board a cargo aircraft. Chang Sha Airport in China together with Wu Xi Fu Jiang are currently changing the game in the logistical handling of this process with the help of robotic solutions. One of the main robot tasks requires that the cargo is reliably marked and at the same time not damaged by excessive pressure during the marking operation. Based on the 3D snapshot camera technology, the Visionary-S of SICK provides the necessary 3D and 2D data to make this possible even when the packaging material and its dimensions are not standardized or a-priori known. The combination of stereovision, structured light illumination and RGB image in one device makes the system suitable for a wide range of applications regardless of external conditions.
The operating principle of the further Visionary family members, such as Visionary-T and Visionary-B, developed by SICK also allows capturing 3D data in one snapshot. Depending on the specific robot task, each product of the Visionary line with its own strengths is suitable to capture the individual images independently of the corresponding belt speed, thus allowing an easy integration into the robotic system.