OmniPreSense is back at it and has released a new FMCW range reporting radar, the OPS241-B. Like the OPS241-A, which is a Doppler radar, the OPS241-B reports the range to objects in its field of view. But not just one object, it will give you the reading for up to 9 different objects in its field of view. And you can get the signal magnitude from the sensor so you have a sense of the size of the object. You may be able to tell the difference between a wall your robot may run into or a person approaching. The OPS241-B can detect people up to 8m (26 ft.) away, cars up to 15m (49 ft.), and the wall of a build up to 20m (66 ft.). It does all this with a fairly tight 7.5cm range resolution.
The OPS241-B is also an Arduino shield board so it can snap right into any Arduino. It communicates over the serial interface or you can use the USB interface to connect directly to a Raspberry Pi. Power consumption is 1.4W when running fully active but has duty cycling capability which can bring power consumption down under 1W.
Compared to ultrasonic, IR, and LiDAR sensors, radar provides a more robust, noise immune solution with a long detection range and wide field of view. In the OPS241-B, the field of view is 78 degrees wide in both the horizontal and vertical direction. It can be used outdoors in the sunlight or on noisy robotic systems. For applications that want a more restricted field of view, OmniPreSense offers electromagnetic lens enclosures which reduces the field of view to 26 degrees. Several code examples are available on the company Github site.