I want to capture Functional Safety concepts. This is an important topic given the number of vehicles and their increasing automation. It was a major topic at the recent ArmTechCon.
Airbags, seat-belts, ABS, and tire-pressure-monitoring-systems are some of the safety features in a car.
Safety Function or Safety Instrumented Function (SIF): A function to take a system to a safe outcome when certain prerequisites on system inputs are not met. For example, turn on a warning indicator when seat-belt is not used or when the tire-pressure is below safe level, or deploy airbags when a collision is detected.
Safety Related Control Function (SRCF): This is the control mechanism by which the safety function is achieved. For example, collision above a certain impact threshold leads to airbag deployment by an airbag control module. Quote: “The airbag control module is installed inside the center console and contains a safety sensor, G sensor, ignition judgment circuit, and a backup power supply.”
Safety Integrity Level (SIL): The reliability of a safety-related-control-function is captured with a Safety Integrity Level or SIL. SIL level go from 1 to 4 (highest). SILs are derived from a risk estimation process and are used in estimating risk of a system built using pre-built components.
A safety standard is ISO26262. The V shaped functional safety process diagram describes the design steps flowing from OEM to supplier and verification steps flowing back from supplier to OEM (here). This process is used to achieve a Safety Integrity Level (SIL) where the SIL1, SIL2, SIL3, SIL4 reduce risk by a progressive factor of 10, i.e. by 10x, 100x, 1000x and 10000x. A hazard and operability study ( HAZOP ) is undertaken to understand the risks of the mechanism behaving incorrectly.
Safety systems for robotics are discussed here – this has a table of typical safety issues when a person enters a robot safeguarded area. Industrial robots security was briefly discussed in this blog here.
An Nvidia safe driving report is here.