The growing use of electronics is driving equipment makers to focus on improving safety and reliability. Both equipment makers and component suppliers are making international standards the basis of their efforts to ensure that electronics aren’t the cause of safety issues.
“The standard ISO 26262 as well as more specific machine directives such as ISO 13849 are guiding machine builders and electronic module providers when considering functional safety on the machine,” said Terry Hershberger, Director Sales, Mobile Machine Sector Management at Bosch Rexroth. “From a functional standpoint the three considerations are fault avoidance, fault detection, and fault control.”
This new focus impacts all component and subsystem suppliers as well as OEMs. Many companies have revamped their design teams in response to this shift in focus.
“Regardless of the device, safety controls take precedence,” said Dave Rodgers, Chief Engineer, Powertrain Controls, at Navistar Defense. “Beyond that, our engine controls and transmission controls work in parallel to meet driver demand to keep safety and performance as primary goals. This is done through the collaboration of powertrain system teams that work together to integrate controls for the engine, transmission, and brakes.”
Component suppliers are also aiding in the drive to meet industry standards. In October, Texas Instruments dramatically upgraded its safe components line.
A dozen versions of its Hercules safety microcontroller line were added along with two complementary devices that are the first to adhere to the SafeTI design package. The multi-rail safety power management integrated circuit and a safety motor driver, as well as the Hercules CPUs, were designed to facilitate compliance with standards such as ISO 26262 and IEC 61508.
Many other semiconductor suppliers are making similar moves. In September, Freescale Semiconductor unveiled a 32-bit microcontroller said to be the semiconductor industry’s first device to be independently certified to meet requirements of ISO 26262. Renesas Electronics rolled out a 32-bit CPU that includes diagnostic functions that provide ISO 26262 support. Sensor makers are also getting in on the act.
“There’s an increased emphasis on safety. Many people are looking at ISO 26262,” said Vincent Hiligsmann, Sensors Product Line Manager at Melexis. “In the powertrain, there’s usually more interest in the gearbox than in the transmission.”
Subsystem suppliers are fine-tuning aspects of their electronic designs all the way from initial design through testing. Eliminating the possibility of failure is a constant focus.
“Circuit layout, board layout, and high population density are all factors on the front end of the reliability story,” Hershberger said. “Circuit boards that have high population density cannot always provide an easy way for bed of nails testing or automated visual inspection of properly installed components.”