As you well have summarized, in order to make vehicles safer to drive, we need to ensure that the driver has his full visual attention on the road. Multi-tasking when done using the same sense such as sight dramatically reduces the response time and accuracy or efficiency of all tasks. However, if the same multiple tasks can be achieved by delineating a task to each sense such as sight, sound, touch then the accuracy and response time remain almost the same. Our brain is wired to handle a single task per sense and that is why sight should always stay focused on the road.
This does leave the other senses such as touch and sound to exploit. Cars already use the touch sense to perform a lot of different tasks such as change tracks, accept incoming calls, raise, lower windows, adjust rear-view and side-view mirrors, even make on-the-fly changes to the way a vehicle performs. We at GetHomeSafe are not exactly sure how touch can be further enhanced unless the steering wheel has a intuitive pattern recognition touch screens. Basically, you could draw a specific pattern to perform certain tasks and this needs no sight interference.
Coming back to speech recognition, it can either be locally or remotely. One need not be present in a vehicle to have access to its controls or communicate with it. For instance, vehicle to vehicle communication may not involve speech but it is remote access and the same can be modified to allow for human interaction. For instance, calling out to your vehicle can let it sound an alarm to alert its presence in the parking lot, lock doors, allow ignition access to a stranger and much more. The current speech recognition in vehicles is limited to accepting calls but remote access is already present in high end vehicles such as voice roadside assistance, manufacturer emergency assistance that detects sudden changes in a car’s parameters and using voice activation can make a call to emergency numbers.
Local speech recognition will allow vehicles to do a lot more automatically. From setting course to maintaining speed, changing lanes and even parking – a lot of driving can be done through speech recognition. This will allow visually impaired individuals to drive and not to mention better vehicle to vehicle communication in future.