STREETSMARTS STEVE STURGESS
ssturgess@truckinginfo.com
Heard On The Bus
Little did the members of the Tech- nology and Maintenance Council of the American Trucking As- sociations realize just what the enabler the standards J1587 and 1708 and the later J1939 would be. These hardware and software protocols for the onboard data- bus on American commercial vehicles were created to ensure some heavy vehi- cle standardization post-1985. Basically, they were conceived so that the long-suffering technicians — who would be faced with servicing the new generation of electronically controlled engines — would be dealing with industry standards rather than captive and propri- etary technologies from each different heavy vehicle manufacturer. And back in the early ’80s when these protocols were being formulated, it was to the vehicle manufacturers’ advantage as well. Back then, customers had the option of Caterpillar, Cummins and Detroit engines. If these engines and the chassis they were engineered into couldn’t talk to each other over standard protocols, the task of engineering them would have been extremely time consuming and costly. But those communication networks enabled by the early protocols today do a whole lot more than feed information to and from the engine ECM. To a large extent, the high-speed J1939 link has made possible the automated mechanical transmission, which in the ZF AS-Tronic/Meritor Freedomline, the Volvo i-Shift and now the excellent Eaton Ultrashift, brings a new level
of safety and fuel economy — not to men- tion driver acceptance — to the heavy truck. Take the UltraShift for example. It makes good use of the databus to work with other controllers on the truck, most notably the anti-lock braking controller to make its hill-hold feature such a great fea- ture. With this, a driver can come off the service brake on a hill and, by stepping on the throttle, release the service brakes for a smooth start without any uncontrolled roll back — or forward. Stability control is another J1939- enabled technology and a brilliant example of what can be made possible when smart engineers have the right tools at their dis- posal. With stability control, the addition of only a few relatively inexpensive sensors makes it possible to predict a likely rollover or skid situation and take a corrective course of action. This involves both the throttle and engine brake through the engine ECM and the individual wheel brakes through the ABS controller. As com- plex as the dynamics of a tractor-trailer or a concrete mixer are, the algorithms that con- trol the selective braking seem capable of dealing with any situation thrown at them. Interactive cruise control is a great con- venience factor. It allows matching the cruise vehicle speed with a vehicle in front until the road is clear to resume a set speed. It helps a driver maintain a fleet-specified following distance without continually latch- ing and unlatching the cruise switch. Now, though, that technology communicates with the engine and the service brakes so that an inattentive driver who may not notice a slowing or stopped vehicle ahead will have the braking responsibility assumed by the vehicle, significantly lessening or avoiding an accident altogether. With dynamic safety under much better control than ever before deemed possible, the databus is now used to enhance pro- ductivity and driver safety in new and exciting ways. Two fairly recent innova- STREETSMARTS IS A MONTHLY COLUMN DEVOTED TO THE ON-HIGHWAY TRUCK MARKETS. STEVESTURGESS IS EXECUTIVE EDITOR OF HEAVYDUTYTRUCKING. HIS E-MAIL ADDRESS IS SSTURGESS@TRUCKINGINFO.COM
4 DIESEL PROGRESS NORTH AMERICAN EDITION February 2010
tions are critical event reporting (CER) and lane departure warning. In the case of CER, the system detects any stability control intervention or hard braking events and reports them to the databus. Communications technologies such as Qualcomm and PeopleNet take that information and broadcast it back to safety managers in real time while taking a snapshot of the event. In fleets where the technology is deployed, safety managers get a text message on their phones and a report via e-mail and are able to query the driver immediately on the nature of the problem. This acts as a significant re- straint, and fleets where this is used see a significant reduction in accidents as well as a prompt identification of a rogue driver. Lane departure warnings from Iteris technology can also be ported into this reporting system so a drowsy or incompe- tent driver is quickly identified. Whatever next? Likely, prognostics or condition-based maintenance. An emerging product, NormNet, without adding any more sensors to the vehicle, polls those already there to determine a pro- file for the vehicle that is “normal.” When sensors start to drift away, NormNet looks at the relationships between all the sensors to determine not only that something is wrong but has a good probability that it will know the cause of the problem. This means dispatch- ers and service managers can make deci- sions about whether to send out a truck or, if already under dispatch, whether to let it complete the mission, get it to a dealer or divert it to one of the fleet’s own terminals. NormNet doesn’t stop the problems from happening, but it allows their management in the best, most cost-effective way. Condition-based maintenance has become the Holy Grail of TMC. Do you think anyone in that organization would have guessed that their new protocols estab- lished 25 years ago would be the enabler for this revolutionary technology? dp
