Hardware in the Loop

Automotive systems are mission-critical. Many are essential for safety and need to function reliably during operation. But modern cars now have a vast array of sensors, including cameras, ultrasonics, radar, LiDAR, temperature and more. This is why Hardware in the Loop testing is so valuable. It allows new ECU designs and their associated software to be assessed under various simulated conditions for performance and durability.

Although these assessments could be made using a complete actual vehicle and previously were in simpler eras of vehicle design, Hardware in the Loop testing reduces the cost and speeds up the process. It is also a highly flexible and available system because the reduced overhead can enable more comprehensive, more frequent assessments. Hardware in the Loop testing can reduce time to market and increase safety.

Where testing to destruction is required, simulating this rather than destroying an actual product will be vastly less expensive. Testing human-machine interfaces can run through many different configurations for users to try so that an optimal design can be discovered more quickly. Some testing might not be legally performed using vehicles on real roads, such as for autonomous vehicle systems. Hardware in the Loop can deliver sufficient regulatory approval for road testing a mature product with most potential problems already ironed out.

Hardware in the Loop testing involves emulated sensors and actuators, which provide the interface between the system under test and the simulated situation. The emulations replicate real-world feedback. The sensors provide inputs, which the system under test then reacts to by delivering actuator outputs. This results in changes in values for the simulation, which will produce new emulated sensor inputs. The results are then assessed against requirements.

For example, an Advanced Driver-Assistance System (ADAS) will be operated in various simulated weather, terrain, and traffic conditions (providing a range of inputs). The system's behavior (outputs) will then be assessed to ensure the ADAS provides the intended level of performance and safety, such as stopping sufficiently quickly when a car in front brakes unexpectedly in heavy rain.