3D radar scanner Keeping a close eye on the surroundings

Related Vendors

Hans Turck GmbH & Co. KG

Wuxi InfiMotion Technology Co., Ltd.

Many radar sensors for collision avoidance only measure distance, thus only providing one dimension as a measurement. In contrast, Turck's new MR15-Q80 radar scanner provides true 3D data, significantly improving the representation of objects and spaces.

Radar technology is usually associated with speed controls in road traffic or aircraft monitoring devices. But since the 2000s, the technology has increasingly also found a use in the car itself. Active distance control systems, called ACC systems (Adaptive Cruise Control), use radar to determine the distance to cars ahead and their speed. Radar is also becoming increasingly used in industrial automation in recent years. Particularly in level and classical distance measurement, the advantages over ultrasound, optosensoric or media-touching technologies pay off in many applications.

Third in the league

In 2020, Turck had already introduced its first radar sensors for level measurement with the LRS series, followed in 2021 by the DR-M30 radar sensors for distance measurement. Both device families operate in the 120 GHz range, which particularly benefits the range and resolution, i.e. the accuracy of the signal. As the third member of the radar portfolio, Turck is now launching the MR15-Q80 radar sensor.

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The different shape of the housing already indicates that another type of device is complementing the product range: In contrast to the cylindrical devices for distances and fill levels, the MR15-Q80 is flat and rectangular. The underlying technology is also different: Inside the robust IP69K housing, an antenna operates at 60 gigahertz. Compared to the 120 GHz frequency band, the lower frequency provides less resolution, but the beam angle broadens significantly. Thus, the MR15-Q80 detects objects with an opening angle of 120 degrees horizontally and 100 degrees vertically.

Mobile Working Machines on a Safe Course

The sensor achieves a range of up to an impressive 15 meters, although this maximum value can also decrease depending on the material, angle, and surface condition of the objects. However, since the target applications are mainly object detection and collision avoidance, users do not have to worry about lack of range.

Turck's new radar scanner achieves the maximum IP69K protection against water and dust intrusion, meeting all the requirements for robustness of components for the mobile equipment sector. The M15-Q80 also scores well in mechanical resilience, being able to withstand shocks and impacts of up to 100 g. This is where radar technology clearly differs from laser-based Lidar technology. Lidar systems require movable mirrors to direct the laser beams into every corner of the area to be captured. These movable mirrors are naturally susceptible to mechanical damage from impacts and vibration.

Robust in many respects

Radars are not only less sensitive to interference factors such as dust, fog or light reflections, but are also much more robust mechanically. In addition to strong shocks, the MR15-Q80 also tolerates supply voltages of 12 or 24 volts used in the electrical systems of mobile work machines — the sensor also survives any possible voltage peaks without damage.

Turck positions the MR15-Q80 as a collision avoidance and object detection sensor for all non-safety critical tasks. It detects objects in its surroundings and — unlike comparable devices — provides measurements for all three dimensions. For mobile work machines, the new radar scanner is currently the only device on the market that can provide three-dimensional measurements via the SAE J1993 communication protocol for the CAN-Bus.

The MR15-Q80 provides distance and speed values for objects on all three spatial axes. This allows the environment and all objects in it to be mapped much more precisely. Especially machines that operate with arms or extensions at different heights receive valuable additional information about their surroundings. Thanks to the 3D information, the control system not only knows where an obstacle starts, but also where it ends and where the machine can operate with its arms. There are many other applications where having an accurate understanding of the space in front of machines can be helpful, such as capturing topography and rock outcrops in mining.

Identification of animals and objects in the field

Another application in the mobile equipment sector is the detection of animals and objects in fields. Turck's radar scanner can be mounted directly on the thresher of the combine harvester to monitor the field ahead of it. Due to the different reflection properties of animals or objects and cereal stems, the sensor can identify foreign bodies in the field that could either be damaged themselves or could damage the threshing mechanism. Thanks to the large opening angles of 120 degrees horizontally and 100 degrees vertically and a range of up to 15 meters, the radar scanner can reliably determine whether the field in front of the combine harvester can be harvested without problems.

For these and other applications, users can define warning radii that trigger a switching signal as soon as an object is within them. Switching signals can also be reliably triggered by certain intensity thresholds, which are important for distinguishing between objects. However, the controller can also fully evaluate the IO-Link signal to utilize the entire information density. Up to six freely definable warning fields and three three-dimensional signal spaces can be taught in and linked to one of the two switching outputs. If one of these warning fields is in the radar shadow because an object is between the sensor and the field, the sensor also recognizes this and sends out a corresponding message.

Keeping the blind spot in view

Another application possibility on mobile working machines is the blind spot warning, i.e., the monitoring of areas on the machine that are difficult to see. If objects are located there, the vehicle can be damaged. The warning radii and signal spaces are also helpful for this purpose to issue warnings in time.

Alternative fields of application are also emerging in intralogistics. In particular, floor conveyors and driverless transport systems (AGVs) require sensors for navigation and collision avoidance. LIDAR scanners are typically used for safety-oriented environment monitoring. However, they are only moderately suitable for vertical monitoring of lifting paths on autonomous forklifts, as they usually cover a small vertical opening angle. Special safety radars and scanners would also be oversized and therefore too expensive for the non-safety-relevant height control function.

Precise and safe control of lifting movements

Turck's 3D radar scanner provides the necessary information for all three spatial dimensions, thus detecting obstacles and surroundings in their entirety. This information also facilitates precise and safe control of lifting movements. The scanned data can also be used to secure overhead clearance and to prevent damage to vehicles, goods and plant components. Cameras systems are often used for these tasks, but they are generally more expensive and more complex to commission.

Configuring such complex sensors, which output more than just an analogue signal or one or two switching signals, often poses a challenge. Turck supports users with its configuration and IIoT software TAS (Turck Automation Suite). The toolkit significantly simplifies commissioning and optimising the signal and intensity filters, detection angles or warning radii. The software visualises all the sensor's raw data in near-real time in a web browser. On two graphs, one for vertical data and one for horizontal detection angles, objects are displayed as points and point clouds.

Turck offers two variants of the 3D radar scanner: one with IO-Link and one with SAE-J1939 interface, which is mainly used for mobile working machines. Both devices have two standard switching outputs in addition to the interface for the 3D data, which can be triggered by different threshold values.

*Raphael Penning is Product Manager Distance Sensors at Turck

The article was firts published on our siter brand 'Konstruktionspraxis' (German Edition), Vogel Communications Group