CAVForth buses are controlled by Fusion Processing's 'CAVstar' Automated Drive System (ADS). CAVstar consists of an Artificial Intelligence (AI) controller and sensing system that enables the vehicle to drive autonomously within its Operational Design Domain (ODD). The ODD describes the area and conditions in which the vehicle is able to drive itself.
The system uses various sources of information including its sensors to gain an understanding of its surroundings, which it uses to ascertain what objects are around it and what they are doing. It also uses this information together with GPS and its in-built map to determine its exact position. With this knowledge the vehicle can calculate (and re-calculate) a safe path to its required destination. The CAVstar system then converts this path to a set of low level instructions to control the vehicle's steering, throttle and brakes.
The CAVForth buses operate to SAE Level 4 Autonomy, which means that they are able to operate safely within their ODD without human intervention, even if there is a system fault. This is achieved by building in redundant steering and braking systems that take over if the primary systems should ever have a problem. The safety driver is never expected to have to take control of the vehicle whilst it is in autonomous mode.
The CAVstar system is designed to identify other road users, such as cars and cyclists and tracks them as them move close to the bus to ensure there are no collisions. The optical cameras, lidars and radar also scan either side of the road for potential pedestrians that may be about to step off the pavement.
Tested over thousands of miles, CAVstar is one of the safest and most reliable automated driving systems available.
The Alexander Dennis Enviro200 buses used on CAVForth are powered by a regular diesel internal combustion engine. We believe that the CAVstar automated drive system will yield up to a 20% fuel saving, over a manually driven version.
Whilst all Enviro200 buses have a regular power steering system, we have added a second system that can safely control the bus should the primary system stop working due to power failure or another fault.
In addition to the normal brakes, a second entirely separate braking system has been added which replaces the primary braking system in the highly unlikely event of a failure.
Fusion Processing’s CAVstar automated driving system typically combines a range of radars, LIDARs and cameras. These enable the AI system to build up a complex picture of the vehicle's environment and help it navigate a safe route, identify other vehicles, vulnerable road users, obstacles, red lights, gaps in traffic etc.
At the heart of the system is the CAVstar controller which includes an Artificial Intelligence engine that receives the inputs from the sensors, communications units and vehicle systems and uses this information to:
- determine the nature of the vehicle's environment, including road topology and lane configuration
- identify the objects around the vehicle
- ascertain the vehicle's exact position
- identify other road users and their trajectories
- calculate a safe path to the vehicle's next destination
- send instructions to the vehicle's actuators ( steering, brakes and throttle) to execute the desired route
- identify any safety hazards to execute safety manoeuvres if necessary
- respond to other road users appropriately at junctions and when lane changes are required
Intelligent Sensing And Control Systems For Autonomous Vehicles
The world's leading provider of AV Level 4 technology for autonomous buses