On May 20, 2021, Dalian General Holdings, a leading semiconductor component distributor dedicated to the Asia-Pacific market, announced that its subsidiary World Peace has launched a binocular stereo vision solution based on NXP S32V234, which can be applied to advanced Driver Assistance Systems (ADAS).

ADAS, as a transitional stage to realize autonomous driving, can help drivers avoid collisions, thereby greatly reducing traffic accidents, and has attracted much attention in recent years. Currently, the more popular ADAS applications are Forward Collision Avoidance (FCW) and Lane Departure (LDW), which can detect surrounding vehicles and pedestrians that may cause accidents or predict lane departures to prevent accidents. function. However, these two applications are limited by the immature vision technology, which can only map specific objects, which limits their application scope.

The binocular stereo vision solution based on NXP S32V234 launched by the United Nations General Assembly World Peace can significantly improve the object recognition rate and recognition types, thereby further improving the related applications in the field of ADAS.

Figure 1 – The Display board of the NXP S32V234-based binocular stereo vision solution launched by World Peace

Binocular stereo vision is to establish a new dimension of object depth through the concept of binocular, and with the design of optical focal length, the distance recognition of objects can be more accurate. This technology can be applied to front vehicle detection and collision avoidance, lane departure, number and sign recognition, pedestrian detection, etc.

This solution is mainly aimed at the detection and discrimination of the preceding vehicle. The system establishes a three-dimensional space through a dedicated binocular stereo vision algorithm. After the two lenses capture the image, the algorithm process analysis is performed according to the parallax value, and the vehicle distance (viewing distance) can be calculated. The larger the difference, the closer the distance, and vice versa).

Figure 2 – Schematic diagram of the principle of binocular stereo vision detection of parallax

The main platform of this solution comes from NXP’s second-generation vision processor series S32V234, which can support computing-intensive image processing applications. The sensor adopts Sony IMX224, which can reach a detection distance of 50 meters in the actual road measurement. At the same time, with the help of the NXP eIQ Auto suite and deep learning framework tailored by the S32V234 APEX vision accelerator, the resolution and detection speed are further improved. The actual measurement shows that the execution speed of this scheme can reach 27 frames per second (27FPS).

In addition, this solution also provides a set of Sky Eye binocular stereo vision ADAS product development prototypes and technical resources, which can enable developers to quickly get started with applications, shorten the development cycle and focus on algorithm development to design high-level ADAS products.

Figure 3-The block diagram of the NXP S32V234-based binocular stereo vision solution

Core technical advantages:

Increase the depth dimension, can identify many objects, and has broad application prospects;

The lenses converge 30cm to expand the parallax effect, which can detect farther vehicles (50 meters);

Complete peripheral configuration: Multimedia Interface (HDMI), Ethernet, Asynchronous Receiver Transmitter Transmitter (UART) interface;

Object recognition is fast and accurate;

Get started with deep learning kits quickly.

Program Specifications:

Main chip MPU specification (NXP S32V234):

With 4 Quad Cortex-A53 high-performance processors, the maximum frequency is 1GHz;

With ISP graphics processor, APEX visual accelerator, GPU graphics accelerator and other cores;

ISP graphics processor provides HDR, color conversion, white balance, automatic exposure and other technologies;

APEX Vision Accelerator consists of 64 small computing units, which can improve computing performance by about 8 times;

GPU graphics accelerator (GC3000), operating speed up to 800 MHz.

Provide 4MB internal memory and DDR3/DDR3L/LPDDR2 external memory;

Provide H.264 image decoding and encoding technology (8-12bit);

Provide SD card, Ethernet and other peripheral interfaces;

It meets the requirements of the vehicle safety specification ISO 26262 and the vehicle safety level ASIL.

Lens Module Camera Module Specifications (Sony IMX224):

Provides a maximum resolution of 1280 (H) x 960 (V) with a total of 1.23 million pixels;

Provides a maximum frame rate of 120 frame/s;

Provide 10 and 12 bit digital to analog converter;

Provides good high-resolution color images in low light sources;

AEC-Q100 Grade 2 Compliant.

External Memory External Memory DDR3 Specifications (MT41K256M16TW-107):

The maximum operating clock is 933 MHz;

The storage capacity is 512 Byte;

Operating voltage is 1.283 to 1.45 V;

Operating temperature is 0 to 95 degrees.

Power Management Integrated Circuit PMIC (PF8100/PF8200) Specifications:

Provides 7 high-efficiency buck converters;

4 linear regulators are provided;

Provide monitor monitoring mechanism;

Complies with ISO 26262 and vehicle safety level ASIL-B.

Low Quiescent Current Synchronous Buck Controller DCDC Specifications (NCV881930):

The working frequency is 410 KHz, with synchronization function;

Provide a stable working current of 30μA;

Provide thermal shutdown (TSD) mechanism;

Compliant with AEC-Q100 and PPAP standards.