研发中心 e-Newsletter 2014年2月份

 

Digital telematics information for emergency dispatchers to save lives

As more vehicles employ telematics, there’s a growing interest in using digital data from a range of electronic controls to tell emergency responders about the severity of an accident. Service providers recently teamed up to demonstrate that these data can be transmitted by itself, to emergency dispatchers without human intervention.

Current systems rely on human operators who call the injured occupants in vehicles after collisions. Then operators locate and contact the nearest emergency dispatch site. The operators often collect and provide relatively sketchy information subject to the reply by injured passengers.

The King County of Washington State's Public Safety Answering Point (PSAP), OnStar and the Rave Mobile Safety have worked together to deliver telematics crash data to the PSAP. That would provide more relevant information useful to dispatchers that eliminate some of the uncertainty when data are otherwise transmitted by people.

In design, digital data pulled from a vehicle’s electronic systems would provide uniformity in a common format that is a lot more comprehensive.

                            

The Rave’s system provides standardized data to emergency responders.

The teams worked with PSAP centers to determine which data are most important. Depending on the age of the vehicle, it can provide information like airbag deployment, the number of front-seat occupants, whether the vehicle rolled over, and its resting orientation. The type of life saving equipment that’s sent out can vary depending on whether it’s resting on its wheels or roof.

Rave’s software also analyzes factors such as the suddenness of speed reduction to calculate the possible severity of injuries. It can also provide other important information such as schematics that show how to disconnect a hybrid’s high-voltage power system.

The OnStar team expects the system will augment its existing emergency call services by providing faster, more seamless information transfer between the OnStar advisor and the local PSAP. It is to further assist first responders by enhancing the profile information presented to them while they are responding; allowing them to access data designed to aid in their response like vehicle schematics and propulsion details.

The demonstration comes as states and communities are beginning to understand the benefits of receiving digital information. Most 911 systems still employ technology designed before the takeoff of the Internet.
The technology that supports 911 today dates back to the 1980s. Most people realize the need to go to an Internet Protcol (IP) technology to open a breadth of data channels, but it’s slow going because it happens at the local level where funds and understanding of the need vary widely.

A number of PSAPs are already starting to adopt IP-based systems that can utilize formatted digital input. The National Emergency Number Association (NENA) and other groups have developed a new system called Next Generation 911 (NG9-1-1), which is to facilitate some adoption.

A few states are already operating NG9-1-1 or NG9-1-1-like systems, according to NENA, the trade association for 911 service providers. It is estimated that most of the United States will have NG9-1-1 in place in the next 5-7 years. However, 9-1-1 is managed at the state and local level. This is largely going to be a state-by-state adoption process.

OEMs will also have to implement technology that gives the vehicle’s emergency software access to relevant data from airbag controllers and other systems. OEMs will also have to employ technologies that provide data in a way that can be understood by PSAPs.

PSAPs don’t care whether data come from a Ford or a Chevy. They want data that’s in a normalized format. Then they can use it to help responders for the saving the lives of accident victims.

Local design

APAS by Innovation Technology Fund has sponsored one Platform project (ITP/003/09AP) that provides telematics info of vehicle status involved in accident. The research team at Chinese University of Hong Kong has demonstrated by prototypes for sending automatically the GPS location of vehicle in accident and the status like activation of airbags, vehicle roll-over, slight bumping and the braking severities. The project results are ready to commercialization with interested clients.

The GSM-based wireless subsystem sends GPS location and accident severity info to the Call center. So that the prompt and appropriate action can be carried out.

 

The accidents/potential accidents are detected and classified into four levels of severity. They include the calculated acceleration & braking values, slight bumping (determined by 3-axis accelerometer with 13 bit resolution) airbag activation and the roll over  (determined by Three Axis Low-g Micromachined Accelerometer).

 
 

Hybrid and Electric Vehicle Range extender design by Mazda

Target to enable hybrids and EVs carrying smaller electric motors and batteries, making them lighter and cheaper, Mazda (company) continues to improve its internal-combustion technology.

Mainstream products involve the piston engines that feature homogeneous-charge compression ignition (HCCI) and adiabatic design.  Meanwhile, the company is aiming at a compact, quiet, and smooth range extender for Electric Vehicle (EV) by its signature Wankel rotary engine to power a small on-board generator.

HCCI and adiabatic development

The company’ current SkyActiv engines employ non-typical compression ratios —14:1 for both gasoline and diesel engines. Its focus on optimal combustion lays the groundwork to move into HCCI.

These engines and their successors will be normally aspirated rather than turbocharged. It is because the normally aspirated engines have quicker response. They suit to company’s focus on “fun-to-drive” cars. And while reduced-displacement turbo engines can achieve high efficiency on standardized tests, such engines commonly disappoint customers with their real-world fuel economy, in the measurements by the company.

Hence the company has continued its refinement of normally aspirated internal-combustion (IC) engines.  IC engines still waste most of their energy in the form of heat. The company has focused to convert more of the waste heat to useful energy for upcoming engines.

A lean-burning HCCI engine will help achieve that using a compression ratio that is even higher than today’s SkyActiv 14:1 ratio. Diesel-like throttleless intake reduces pumping losses, and the company aims to trim friction losses by 20%. Together these changes will boost fuel economy by 30% over today’s engines.

HCCI engines are limited in the load range in which they can run in HCCI mode, but the company expects to expand that range with improvements to the fuel injection system. Meanwhile, matching the HCCI engine to a hybrid electric drivetrain will let the HCCI gas engine run in its most efficient operating range, allowing the electric motor assist as needed.

In this de-emphasized role, the electric motor and battery need not be as large as in conventional hybrids, hence reducing their cost.

These improvements to the engine reduce the energy loss through the exhaust but increase the heat loss to the cooling system. For SkyActiv 3, Mazda is pursuing adiabatic combustion, using insulation and possibly ceramic materials to minimize cooling-related efficiency losses. The timetable for the delivery of these technologies is coming shortly.

Rotary redux?

Meanwhile, the company is pursuing a new way to preserve the relevance of its signature rotary engine, which was dropped from production in late 2011 due to steadily decreasing volumes (in the RX-8 sports car). The rotary has struggled since the 1990s to meet increasingly stringent emission regulations.

The engineers at Mazda are very proud of the rotary engine and hence have been continuing research and development of the rotary.

By six decades of experience with the rotary engine technology, the company team has thorough understanding of the combustion of piston-engine programs. In particular, the company is taking a hard-eyed approach to its potential return to production. The technology will be used when proven profitable.

One potential application would be to address driver concerns about electric vehicle range. Mazda2 EV customers list driving range as a top concern, and using a rotary-powered range extender would alleviate that range anxiety.

Aside from the company’ desire to find a 21st century role for the rotary engine, the design carries other benefits in comparison to a piston engine of equivalent power. For example, radiated noise, measured from 50 cm (7.8 in) with the engine running at 3000 rpm while producing 25 kW, is 87 dB for a rotary, compared to 92 dB for a gas engine and 96 dB for a diesel.

A chart of vehicle road and wind noise at speed closely tracks one showing the noise produced by a rotary range extender while making enough power to propel a car at those speeds. This means that an EV can use a pistonless rotary-powered range extender without the driver ever hearing it run, unlike range-extender hybrids such as the Chevrolet Volt and Cadillac ELR that use reciprocating engines to extend their EV range.

A 330-cm3 single-rotor Wankel can produce 22 kW (29.5-hp) at 4500 rpm or 28 kW (37.5-hp) at 6000 rpm, according to the company. Its compact size means it fits easily beneath the rear load floor of a subcompact Mazda2.

                             

Mazda illustrates how its compact 330-cc single-rotor rotary engine (shaded blue here) compares in size to a piston engine of equivalent power.

Audi once demonstrated a similar solution in its A1 e-tron concept of 2011, which used a 15-kW (20-hp) 254-cc engine. The company never developed the concept for production, however, saying it wasn’t cost-effective. Audi’s design stacked the generator atop the rotary engine, with a direct connection driving the generator at engine speed. Engineering-services companies AVL and FEV also have shown Wankel-based range-extended EV proposals that are under development. 

Mazda’s design makes a key change. Aside from the slightly larger displacement at 330-cc, Mazda’s approach installs the gas engine and generator side by side, with a belt drive geared to double the speed of the generator.  The faster spinning generator is 5% more efficient than one turning at engine speed, and Mazda’s generator produces a continuous 20 kW (27 hp).

Mazda has survived in a market dominated by much larger rivals by its unconventional approaches to design and engineering, so the company has continued to bringing unorthodox solutions like these rotary engines to market.