How to Design an Automotive In-Vehicle Gesture Detection System and More Using a Multifunctional 60GHz Radar Sensor

“Gesture detection systems offer drivers a new experience: control the interior temperature, lighting, windows, infotainment systems and more with a single wave of a hand. There are many ways to adjust various comfort and convenience functions in the car, but manipulating buttons, knobs, and especially touchscreens, can distract the driver.

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Gesture detection systems offer drivers a new experience: control the interior temperature, lighting, windows, infotainment systems and more with a single wave of a hand. There are many ways to adjust various comfort and convenience functions in the car, but manipulating buttons, knobs, and especially touchscreens, can distract the driver.

In-car sensor solutions in many cars today are mostly based on front-end time-of-flight (ToF) or cameras, but these are not intelligent and cannot be used for a variety of applications. Imagine if the same device used for gesture control could also detect the movements of a child left in the car, or alert the car owner when an uninvited guest tries to enter, even if the car is powered off. Instead of using multiple sensors, a single multi-function sensor can handle these scenarios in different modes.

How multifunctional sensors enable gesture control and in-vehicle sensing

With TI mmWave radar technology, the system is able to detect multiple gestures, such as hand waving (left-to-right, right-to-left, top-down, bottom-up), without the use of touch buttons or knobs. TI’s AWR6843AOP (Antenna On Package) mmWave sensor enables high-accuracy gesture detection (even through materials). Its small form factor allows flexible placement anywhere in the vehicle (such as in the top console or dashboard).

The sensors can operate in all lighting conditions and provide the system with data parameters (such as distance, angle, and speed within the vehicle) by leveraging 3D point cloud information. The multi-mode capabilities of TI’s mmWave sensors make them suitable for a variety of sensor-dependent applications, saving design time and cost.

The AWR6843AOP Evaluation Module (EVM) features an integrated AOP that helps simplify the RF design process and enables a 120-degree field of view in azimuth and elevation (horizontal and vertical views). The EVM can be installed on the front of the dashboard of the vehicle, with a detection distance of 4m and a distance resolution of 4cm.

Some example gestures include: waving from left to right, waving from right to left, and waving from top to bottom and bottom to top. Since parameters such as hand distance, movement speed, and gesture angle are all detectable, sensors can be programmed to recognize various gestures based on their Doppler signatures.

Multi-mode functionality all on one chip

TI’s smart integrated mmWave chips provide multiple functions on a single device. For example, when the car is powered off, the sensor can be in a low-power state, providing child or intrusion detection in the car. When the car is powered on, the sensors can detect gestures. With this feature, there is no need to install multiple independent sensors for various applications.

Flexible interior layout

TI mmWave sensors are based on a wide field of view and the ability of mmWave to sense through materials, allowing for more flexible placement within the vehicle. Depending on the application, you can integrate sensors into the dashboard, top console, or even second or third row seats for more personalized applications (such as lighting, entertainment screens, or passenger adjustment of temperature or audio) .

Sensing is not affected by lighting conditions

Because TI sensors use millimeter-wave radar to measure by sending and receiving electromagnetic waves, they are not affected by any lighting conditions in the vehicle. Other solutions are susceptible to false positives caused by direct sunlight, while camera-based solutions may not be fully functional in dark environments.

In-vehicle sensors can do more with less cost and design time

TI mmWave sensors are smart solutions for in-vehicle gesture sensing, enabling functions such as lighting control, door opening/closing, media control, audio control, and human machine interface (HMI) control. When used in HMI systems, TI’s AWR6843AOP enables high-accuracy detection with multi-mode capability for flexible placement and sensing of multiple gestures.

Rethink in-car sensing and design flexibility

Because TI’s versatile AWR6843AOP enables robust multi-mode sensing across a wide range of lighting and temperature conditions, you can perform more in-vehicle sensing functions with fewer components. The package size of TI’s AOP technology is 25% smaller than that of non-AOP devices, enabling design flexibility and easy placement in space-constrained areas, such as overhead consoles or vehicle pillars. Objects blocking the sensor will not affect the high-performance radar, which can penetrate materials to detect children in the back seat or recognize various gestures to control vehicle systems.