The videos below demonstrate how the semi-autonomous navigation framework (patents pending) developed in Sterling's Master's research interacts with a human driver. Each of the videos below overlays the results from two simulations: the gray vehicle is controlled solely by a human driver model whereas the blue vehicle is also fitted with the semi-autonomous controller. What follows demonstrates a few of this framework's numerous advantages.
Static Hazards
The results below demonstrate the navigation framework's performance in the presence of static (ie. stationary) hazards such as road edges, roadway obstacles, etc.
In this simulation, the driver of both vehicles actively seeks to remain on the road surface -- a difficult feat at 20 m/s (~44 mph)
Notice that including the semi-autonomous controller in the control loop not only keeps the vehicle stable, but also moderates the driver's inputs in the process. Whereas the unassisted driver oversteers and looses control of the vehicle, the assisted driver notices that the vehicle is responding as desired and is thus more moderate in his steer commands. This, allows him to maintain control of the vehicle. Moreover, allocating less than 50% of the available control authority to the controller (see green bar on the right) is sufficient to keep the vehicle on the navigable roadway and within 0.4 meters of the line the driver is trying to track. The combined effect of both inputs (driver and controller) is a vehicle trajectory that more closely tracks the path the driver is trying to follow than the driver could accomplish on his own.
Driver Inaction
The tests below show how the semi-automous controller responds when the driver fails to steer around an impending threat. Notice that in these scenarios, the controller intervenes only enough keep the vehicle safely on the navigable road surface. Once the threat has been reduced, it gives complete control back to the driver.
Dynamic Hazards
The videos below demonstrate the semi-autonomous controller's ability to avoid moving hazards. As publications describing these simulations are pending, these videos are provided without additional commentary. For now, suffice it to say that the driver input in both cases is identical: he maintains his steering angle at 0 degrees as though he does not see the impending hazards. Notice that the host vehicle (blue and gray) maintains a constant velocity (~44 mph) while other vehicles (red and yellow) accelerate and decelerate.
Finally, the simulation below demonstrates how, in the absence of control inputs from the human driver, the semi-autonomous controller effectively behaves much like an alert driver would - seeking first to pass, then pulling back in behind the other vehicle as it accelerates.
