What ‘ADAR’ Means for Future Robotics Deployments in Busy Packaging Facilities

With humans and robots sharing spaces more than ever before, it’s essential that robots can detect people and property effectively to ensure safe operation. Image courtesy of Sonair

An exclusive Packaging Technology Today interview with Ole Marius Rindal, Co-founder of Sonair

Packaging, logistics and warehouse facilities are increasingly adopting autonomous mobile robots (AMRs) to increase productivity and throughput, address labor challenges, and reduce waste. Ole Marius Rindal, the co-founder of Sonair, explains how advances in obstacle detection technology can ensure safer interaction between robots, humans and equipment in busy packaging facilities:

Why are AMRs at the forefront of the automation trend?

AMRs perform a wide range of tasks including material handling, line feeding and finished goods handling. With a robot arm mounted, AMRs can also be deployed on packaging, palletizing, quality control and inventory management applications.

AMRs deliver goods to conveyors, where they are packaged by humans (or robots). When the packaging process is complete, goods are sent down the conveyor to be picked up by an AMR and delivered to a truck for outside delivery.

With humans and robots sharing the same facilities -and often sharing the same workspace- safety is extremely important. With safety in mind, AMRs are packed with a variety of sensors to perform critical safety functions such as object detection even in dynamic environments.

Object detection enables AMRs to avoid collisions, enhances human robot interactions, increases operational efficiency and reduces wear and tear on the AMR itself. Obstacle detection is typically achieved through a combination of sensors, such as 2D safety rated light detection and ranging (LiDAR) and 3D cameras, or 3D LiDAR combined with stereo cameras.

These sensor combinations get expensive quickly, don’t they?

Absolutely. In fact, the typical sensor package on an AMR accounts for up to 30% or more of the total hardware cost of the robot.

Is there any way to bring this cost down without sacrificing robots’ obstacle detection capabilities?

Yes. In fact, there is a way to bring down the cost of AMRs while improving their obstacle detection capabilities versus current 2D safety LiDAR systems.

The key is a new, award-winning, 3D ultrasonic sensor that uses acoustic detection and ranging (ADAR) to provide 3D depth sensing and obstacle detection with a range of up to five meters (16.4ft). Deploying four of the new sensors on an AMR (front, back, and both sides) enables 360-degree sensing.

2D LiDARs have limited Field of View and can only sense a narrow two-dimensional slice of the environment around a robot. In contrast, ADAR-based sensors provide autonomous mobile robots with a full 360 degree protection from obstacles and at a 50% lower cost compared to 2D LiDAR-based alternatives. Graphic courtesy of Sonair

What is ADAR?

ADAR refers to ‘acoustic detection and ranging’ – a completely new category of sensor that enables 3D ultrasound imaging in the air. ADAR can be considered alongside established technologies like SONAR and RADAR. The key difference, of course, is that ADAR works acoustically in the air, whereas the others work underwater and with radio frequencies, respectively.

Don’t ultrasound in air sensors already exist?

Yes, but the most common — the parking sensors on your car — are one dimensional, so they sense in just one direction and provide distance information only.

By contrast, the innovative, new ADAR-based sensor provides the x, y, z coordinates necessary to create a 3D view. This opens a host of possibilities for using ADAR-based sensors in robots to ensure that automation operates safely in shared spaces with humans.

What advances made this new sensor possible?

Beamforming — the principle that underlies ADAR and well-established ultrasound technologies from 3D medical ultrasound imaging to SONAR — allows sensors to transmit and receive sound from different directions. But beamforming in air requires transducers that are small enough to be spaced half a wavelength (λ/2) apart.

A team of Nordic researchers managed to build miniaturized transducers to enable beamforming in air for the first time.¹ In addition, the researchers found that they could apply modified versions of the algorithms used in medical ultrasound imaging on the new sensor, confirming that the new technology could readily perform depth sensing and obstacle detection.

2D safety LiDAR sensors are typically used for obstacle detection. What advantages does the new 3D ultrasound sensor have over 2D safety LiDAR?

LiDAR has known limitations when it comes to effective obstacle detection. For example, LiDARs have limited Field of View (FOV) and can only sense a small, two-dimensional slice of the environment around a robot. This means that LiDAR cannot detect objects outside the 2D plane.

Moreover, 2D safety LiDAR are typically mounted on AMRs at a height of around 20cm (7.9in). This means that 2D safety LiDAR won’t detect objects that are 10 centimeters above the floor. Similarly, 2D safety LiDAR won’t detect objects hanging from the roof or items sticking out from walls or shelves if they are outside the sensor’s limited FOV.

Meanwhile, various lighting conditions can create additional challenges for LiDAR, as do transparent surfaces, which LiDAR struggles with.

The new, award winning 3D ultrasonic sensor provides greatly enhanced obstacle detection versus 2D safety LiDAR.

How does the new ADAR-based sensor compare to 2D safety LiDAR in terms of cost?

A 2D safety certified LiDAR typically costs about $4,000 whereas the new 3D ultrasound sensor will cost around $1,000 when it’s officially released later in 2025.

With AMRs typically carrying two 2D safety LiDAR, removing these expensive sensors produces an immediate $8000 in savings. Deploying four ADAR-based sensors instead, at an approximate cost of $4,000, provides the AMR with a full 360-degree protection from obstacles and at 50% lower cost compared to 2D LiDAR-based alternatives.

Acoustic detection and ranging (ADAR) is a completely new category of sensor that enables 3D ultrasound imaging in the air. Graphic courtesy of Sonair.

Don’t 2D safety LiDAR support other functions besides obstacle detection?

Yes. 2D safety LiDAR are also used to support autonomous navigation capabilities, for example. To retain those capabilities, robot designers could use the new sensor with much cheaper, non-safety rated LiDAR, which costs around $500, while the new sensor performs the improved 3D safe obstacle detection function.

Depending on the configuration, the new ADAR-based sensor technology reduces the cost of the typical safety sensor package by between 50 and 80% – while boosting safety.

This is good for both robot builders who can develop safer robots at lower cost, and good for their customers at packaging facilities as the price of advanced, safe industrial mobile robots drops.

What does all this mean for humans working in packaging and palletizing facilities?

With humans and robots sharing spaces more than ever before, it’s essential that robots can detect people and property effectively to ensure safe operation.

For humans, knowing that the robots around them possess 360-degree depth sensing and obstacle detection provides peace of mind. Meanwhile, technology buyers at packaging facilities appreciate the lower hardware costs.

Down the line, the technology could even be applied to entire robot cells, ensuring safety not just in a 5m range around a robot, but across an entire automated packaging or palletizing cell.

Is the new 3D ultrasonic sensor limited to AMRs?

Far from it. While AMRs are the focus of our early access program, any robot that coexists and shares space with humans -such as humanoids, robot arms and automated forklifts- can benefit from the improved obstacle detection provided by the new sensor – and at a greatly reduced cost than 2D safety LiDAR.

For More Information

A new ADAR sensor is on schedule to achieve full safety certification (IEC 61508 and SIL2) in late 2025, and will be commercially released before that. Once the safety certification is confirmed, all users will need to do is download and install a firmware upgrade to bring the device up to date.  Learn more at:  https://www.sonair.com/journal/our-moment-of-truth

References

1. https://www.sonair.com/journal/deep-dive-3d-ultrasonic-in-air