Intelligent Speed Adaptation (ISA)

Intelligent Speed Adaptation (ISA) is a component of Advanced Driver Assistance Systems (ADAS) that’s designed to assist drivers in adhering to speed limits. The primary objective of ISA is to reduce speeding and promote safer, more environmentally friendly driving practices.

ISA gets its data from various sources, including traffic-sign recognition cameras, GPS speed limit maps, or a fusion of both. In cases where camera and radar sensors are combined with map data, the map serves as a supplementary source, extending the sensor range, and providing a backup when visibility is poor.

The system compares the vehicle’s actual speed with the speed limit of the current road or those found in residential areas, city limits, and highway entry signs. With this data, ISA can provide feedback and assist the driver in adhering to the appropriate speed restrictions.

Additionally, ISA can consider speed limits based on the time of day and current weather conditions. In the future, ISA systems will have the potential to leverage information from other connected vehicles through the Internet of Vehicles (IoV) to enhance the system’s effectiveness.

If ISA detects that the vehicle is exceeding the speed limit, it will alert the driver. ISA systems can be categorised into passive and active systems based on the type of reaction they offer. Alternatively, the feedback from an ISA system can combine elements of both approaches.

Passive ISA

Passive ISA provides drivers with feedback regarding their speed and speed limits but does not actively intervene to control the vehicle’s speed.

An ISA system will provide visual, haptic, or auditory warnings, or a combination of all three, to prompt the driver to slow down.

The role of passive ISA is to rely on the driver’s voluntary compliance with the provided speed limit information.

Active ISA

Active ISA systems are capable of actively intervening to control the vehicle’s speed and ensure compliance with speed limits. For example, one method is to slowly increase the upward pressure on the accelerator pedal, pushing the driver’s foot back. This aims to make the driver aware of speeding and assist in slowing down the vehicle. However, if necessary, the driver can override the intervention by pushing the pedal slightly deeper.

Furthermore, active ISA systems can reduce the fuel flow to the engine, which leads to a gradual decrease in vehicle speed. If the driver wishes to exceed the speed limit, they may need to perform a ‘kick-down’ action to override the intervention.

It’s important to note that ISA does not take over the vehicle’s brakes. The driver will remain in full control and can manually override the ISA system or temporarily disable it.

Benefits and Drawbacks

By assisting drivers to stay within speed limits, ISA can reduce the risk of accidents. Studies have shown that the installation of ISA systems can result in a 30% reduction in collisions and approximately a 20% decrease in road fatalities.

Moreover, having an ISA system in place can provide environmental benefits. Driving at steady speeds and avoiding unnecessary acceleration contributes to improved fuel efficiency, thereby reducing CO₂ emissions.

The system, however, does come with some drawbacks. One potential risk is over-reliance on ISA, which can lead to complacency and reduced attention while driving. At the same time, some drivers may have strong views about the limitations imposed on their control over the vehicle’s speed.

False alerts, incorrect speed limit recognition due to GPS glitches, or errors in reading traffic signs can result in erroneous or inconsistent information being presented to drivers. Additionally, ISA may not always consider situations that justify deviations from speed limits. This can potentially lead to driver frustration and result in them disabling the ISA system altogether.

The Status in the EU

The General Vehicle Safety Regulation (EU) 2019/2144 has made Intelligent Speed Adaptation mandatory across the European Union. According to the regulation, starting from July 2022, all new vehicle models or types introduced to the market must be equipped with ISA. By July 7, 2024, all new cars sold in the European Union must be equipped with ISA. The vehicles already registered and in use before that date will not be affected by this requirement.

The regulation aims to enhance road safety, improve air quality, mitigate climate change, provide innovative mobility solutions, and maintain the competitiveness of the European automotive industry.