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Self-driving cars

Renesas provides chips for Toyota

Published 2017-11-14

Toyota, Denso, and Renesas cooperate in developing electronics for autonomous driving. The chipmaker contributes with its R-Car system-on-chips (SoC) and its RH850 micro-controllers, which both feature CAN FD connectivity.

Toyota’s 2.0 prototype of an autonomous driving car; the next generation of self-driving cars will be equipped with ECUs from Denso using the R-Car and RH850 processors by Renesas (Photo: TRI)

Toyota plans to launch its autonomous-driving vehicles in 2020. The prototype, developed under the name “Highway Teammate” will be equipped with electronic control units (ECU) by Denso. Toyota and Denso selected Renesas as processor supplier. The chipmaker supplies its R-Car SoC family, which will serve as an electronic brain for in-vehicle infotainment and advanced driver-assistance systems (ADAS), and the RH850 series for automotive control. This combination delivers a semiconductor solution that covers peripheral recognition, driving judgment, and body control.

The selected SoC and MCU families provide security functionality to protect the vehicles’ electronics against cyber attacks. Functional safety technology is also implemented. Production-ready autonomous-driving vehicles will require these capabilities as well as the expertise to match these technologies to actual use cases.

Typical combination of R-Car and RH850, CAN FD provides the connectivity to other ECUs (Photo: Renesas)

The SoC will be integrated in Denso’s engine control units. It will be responsible, for example, to locate the vehicle in its environment and to make real-time decisions on vehicle and active safety maneuvers based on sensor data. The RH850 has been selected to control driving, steering, and braking functions, which will be double-checked by the SoC. This combination provides a balance between performance and power consumption, and serves as an autonomous-driving solution, which had a decisive influence on the adoption by Toyota and Denso.

“To achieve a society where mobility means safety, efficiency, and freedom, Toyota is constantly seeking out the latest technology and selecting systems incorporating the very best devices and materials,” said Ken Koibuchi from Toyota. “We are partnering with Denso and Renesas, who bring superior technology and expertise to this project, with the aim to accelerate the development of autonomous-driving vehicles and encourage early adoption.”

“We are collaborating with Renesas to develop an ECU, the so-called electronic brain, for use in Toyota’s autonomous-driving vehicle,” said Hajime Kumabe from Denso. “We will maximize our sophisticated system design and software development capabilities by leveraging Renesas’ high-performance semiconductor devices to realize a highly reliable ECU system for autonomous-driving vehicles.”

“We are delighted that Toyota and Denso have selected our high-performance automotive semiconductor devices for use in the autonomous-driving vehicle they are developing for commercial release,” said Ryuji Omura from Renesas.

(Photo: Renesas)

The processors provide multiple interfaces to communicate with sensors and other peripherals. Both product lines, R-Car and RH850, support CAN FD connectivity. The SoC features also Ethernet and USB connectivity. The R-Car D3 has been introduced specifically for autonomous driving. It provides all necessary interfaces for the connections between the instrument cluster and various sensors, information, and control devices. This is leading to an increasing amount of information being displayed on the instrument cluster to realize, including information on the vicinity of the car during driving. At the same time, from the point of view of safety, the need for visibility is increasing, and it is necessary to render graphics smoothly. Also, due to advances in LCD display technology, the trends towards larger sizes, higher resolution, and lower costs in automotive LCD displays are progressing. As a result, 3D clusters are becoming more widely used in the instrument cluster field, mainly in high-end cars.

The R-Car D3 coming with two CAN FD ports addresses rendering of 3D graphics and reduce development steps and costs, which are challenges for the development of entry-class 3D clusters. Using the PowerVR Series8XE 3D graphics cores from Imagination Technologies, the R-Car D3 achieves approximately six times the rendering performance of the predecessor R-Car D1. System developers creates 3D clusters using low-cost 4-layer printed circuit boards (PCB) and reduce the number of parts, that enables reduced system bill of materials (BOM) costs and achieves system costs as low as current 2D cluster systems.

‘Chauffeur’ and ‘Guardian’

Already in March 2017, Toyota presented its 2.0 generation advanced safety research vehicle at the company’s Prius Challenge event in Sonoma California. The new test vehicle is used to explore autonomous driving capabilities. The Japanese carmaker’s work on autonomous vehicles in the United States began in 2005 at Toyota Research Institute (TRI) in Ann Arbor (MI). The company secured its first U.S. patents in the field in 2006. According to a report last year by the Intellectual Property and Science division of Thomson Reuters, Toyota holds more patents in the field than any other company.

“This new advanced safety research vehicle is the first autonomous testing platform developed entirely by TRI, and reflects the rapid progress of our autonomous driving program,” said Gill Pratt, CEO of the TRI. The developments are focusing on machine vision and machine learning. The layered and overlapping lidar, radar, and camera sensor array reduces the need to depend too heavily on high-definition maps – especially for near-term systems which will be designed for use in areas where such maps don’t exist yet.

The platform is the second generation of the advanced safety research vehicle revealed to the public by Toyota at the 2013 Consumer Electronics Show (CES). It is built on a current generation Lexus LS 600hL, which features a drive-by-wire interface. The 2.0 platform has to develop both of TRI’s core research paths: ‘Chauffeur’ and ‘Guardian’ systems. ‘Chauffeur’ refers to the always deployed, autonomous system classified by SAE as unrestricted Level 5 autonomy and Level 4 restricted and geo-fenced operation. ‘Guardian’ is a driver assist system constantly monitoring the driving environment inside and outside the vehicle, ready to alert the driver of potential dangers and stepping in when needed to assist in crash avoidance.

“Basically, it is a smart vehicle designed to get smarter over time,” said Pratt. “It will learn individual driver habits and abilities and will benefit from shared intelligence from other cars as data gathering, sharing and connectivity technologies advance. We believe Guardian can probably be deployed sooner and more widely than Chauffeur, providing high-level driver-assist features capable of helping mitigate collisions and save lives, sooner rather than later.”

Toyota’s approach to Automatic Emergency Braking (AEB) shows a similar commitment. It will be standard equipment on nearly every model and trim level of Lexus and Toyota vehicles in the US by the end of 2017, five years ahead of NHTSA’s (National Highway Traffic Safety Administration) 2022 target date.

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