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Southwest Research Institute developed an Autonomous Ground Vehicle (AGV) capable of navigating in urban environments. The paper first gives an overview of hardware and software onboard the vehicle. The systems onboard are classified into perception, intelligence, and command and control modules to mimic a human driver. Perception deals with sensing from the world and translating it into situation awareness. This awareness is then fed into intelligence modules. Intelligence modules take inputs from the user to understand the need to navigate from its current location to another destination and, then, generate a path between them on urban, drivable surfaces using its internal urban database. Situational awareness helps intelligence to update the path in real time by avoiding any static/moving obstacles while following traffic rules.

For transmission suppliers tooled primarily for producing manual transmissions, retrofitting a manual transmission with actuators and a controller is business viable. It offers a low cost convenience for the consumer without losing fuel economy when compared to torque converter type automatics. For heavy duty truck fleets even the estimated 3% gain in fuel economy that the Automated Manual Transmission (AMT) offers over the manual transmission can result in lower operational costs. This paper provides a case study using a light duty transmission retrofitted with electric actuation for gears and the clutch. A high level description of the control algorithms and hardware is included. Clutch control is the most significant component of the AMT controller and it is addressed in detail during operations such as vehicle launch from rest, launch from coast and launch on grades.

Brake energy recovery is one of the key components in today's hybrid vehicles that allows for increased fuel economy. Typically, major engineering changes are required in the drivetrain to achieve these gains. The objective of this paper is to present a concept of capturing brake energy in a mild hybrid approach without any major modifications to the drivetrain or other vehicular systems. With fuel costs rising, the additional component cost incurred in the presented concept may be recovered quickly. In today's vehicles, alternators supply the electrical power for the engine and vehicle accessories whenever the engine is running. As vehicle electrical demands increase, this load is an ever-increasing part of the engine's output, negatively impacting fuel economy. By using a regenerative device (alternator) on the drive shaft (or any other part of the power train), electrical energy can be captured during braking.

During city traffic or heavily congested roads, a vehicle can consume a substantial amount of fuel idling when the vehicle is stopped. Due to regulation enforcement, auto manufacturers are developing systems to increase the mileage and reduce emissions. Turning off the engine at traffic lights and regenerative braking systems are simple ways to reduce emissions and fuel consumption. In order to develop strong manufacturer and consumer interest, this type of operation needs to be automated such that the stop/start functionality requires no driver interaction and takes place without the intervention of the vehicle operator. Valeo Electrical Systems has developed such a system that replaces the OEM engine alternator with a starter/alternator driven by a standard multi-ribbed V belt. To avoid a break and dual voltage network, this system is based on a 12V electrical system using an Enhanced Power Supply.

This paper describes the development of a generic test cell software designed to overcome many vehicle-component testing difficulties by introducing modern, real-time control and simulation capabilities directly to laboratory test environments. Successfully demonstrated in a transmission test cell system, this software eliminated the need for internal combustion engines (ICE) and test-track vehicles. It incorporated the control of an advanced AC induction motor that electrically simulated the ICE and a DC dynamometer that electrically replicated vehicle loads. Engine behaviors controlled by the software included not only the average crankshaft torque production but also engine inertia and firing pulses, particularly during shifts. Vehicle loads included rolling resistance, aerodynamic drag, grade, and more importantly, vehicle inertia corresponding to sport utility, light truck, or passenger cars.

In off-highway applications the engine torque is distributed between the transmission (propulsion) and other accessories such as power steering, air conditioning and implements. Electronic controls offer the opportunity to more efficiently manage the control of the engine and transmission as an integrated system. This paper deals with development of a steepest descent algorithm for maximizing the efficiency of hydrostatic transmission along with the engine in the presence of accessory load. The methodology is illustrated with an example. The strategy can be extended to the full hydro-mechanical configuration as required. Applications of this approach include adjusting for component wear and intelligent energy management between different accessories for possible size reduction of powertrain components. The potential benefits of this strategy are improved fuel efficiency and operator productivity.