Constraint-based planning and control for safe, semi-autonomous operation of vehicles

• This paper presents a new approach to semi-autonomous vehicle hazard avoidance and stability control, based on the design and selective enforcement of constraints. This differs from traditional approaches that rely on the planning and tracking of paths. This emphasis on constraints facilitates "minimally-invasive" control for human-machine systems; instead of forcing a human operator to follow an automation-determined path, the constraint-based approach identifies safe homotopies, and allows the operator to navigate freely within them, introducing control action only as necessary to ensure that the vehicle does not violate safety constraints. The method evaluates candidate homotopies based on "restrictiveness", rather than traditional measures of path goodness, and designs and enforces requisite constraints on the human's control commands to ensure that the vehicle never leaves the controllable subset of a desired homotopy. Identification of these homotopic classes in off-road environments is performed using geometric constructs. The goodness of competing homotopies and their associated constraints is then characterized using geometric heuristics. Finally, input limits satisfying homotopy and vehicle dynamic constraints are enforced using threat-based feedback mechanisms to ensure that the vehicle avoids collisions and instability while preserving the human operator's situational awareness and mental models. The methods developed in this work are shown in simulation and experimentally demonstrated in safe, high-speed teleoperation of an unmanned ground vehicle. © 2012 IEEE.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Elektroteknik och elektronik -- Robotteknik och automation (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Electrical Engineering, Electronic Engineering, Information Engineering -- Robotics (hsv//eng)

Keyword

Hazards

Humans

Planning

Torque

Vehicle dynamics

Vehicles

Wheels

collision avoidance

man-machine systems

navigation

remotely operated vehicles

road safety

stability

automation-determined path

constraint-based approach

constraint-based control

constraint-based planning

geometric constructs

geometric heuristics

hazard avoidance

high-speed teleoperation

homotopic classes

human-machine systems

mental models

minimally-invasive control

off-road environments

path planning

path tracking

safe vehicle operation

semi-autonomous vehicle operation

situational awareness

stability control

threat-based feedback mechanisms

unmanned ground vehicle

vehicle dynamic constraints

Semi-Autonomous control

human-machine interaction

obstacle avoidance

planning

shared adaptive control

teleoperation

unmanned ground vehicles

Publication and Content Type

ref (subject category)

kon (subject category)