Most driverless cars use laser sensors, or LiDAR (light detection and ranging), to provide a 360-degree view of what’s happening around the vehicle and spot obstacles. The recent advances in LiDAR technology allow cars to see with extreme accuracy not just where objects are, but what they are — even at distance. However, LiDAR developers are still struggling to reduce costs, improving capabilities to allow decisions at high speed, and increase manufacturing to ensure availability.
Such concerns have pushed automotive lidar system developer Luminar Technologies to develop a new lidar sensor that it believes will help driverless cars see the environment at extended distances and with more details to cope better at high speeds – than other sensors currently available. This means that a car driving on a highway at a high-speed will get additional time to take action when it sees an obstacle. Apart from that, the company said it has designed its sensor to scale up production and slash costs.
Ability to see dark objects at farther distances
The company claimed that its sensor will enable the car to see hard-to-see, dark objects with an industry-standard 10 percent reflectivity (that absorb 90% of light)—even from 200m away. In contrast, cars can only see 30-40 meters out at 10% using today’s technologies.
To extend range, Luminar’s sensor uses the eye-safe 1550 nm wavelength lasers, a longer wavelength of light than sensors on vehicles today, allowing the sensor to fire 40 times more powerful pulses than competitors without violating eye safety rules.
The sensor is also said to allow zoom in on a particular object by directing more laser beams in that direction, using a system of small, moving mirrors that actively steer its laser.
The cost benefit
Most LIDAR manufacturers use silicon to build their receivers because it’s cheap. But silicon can’t detect light at 1550nm wavelength. Silicon-based receivers work at 905nm and offer a limited range.
Using 1550nm wavelength of light required Luminar to use an expensive semiconductor material ‘indium gallium arsenide (InGaAs)’ in the receiver. One of the steps to get around the cost challenge was an acquisition of chip design firm Black Forest Engineering to help build the sensor on a commercial scale.
Luminar says it will be ready to produce and ship a first pilot run of 10,000 InGaAs LiDARs this year.