Defining the market
As mentioned above, the operation of an on-highway truck or a fleet of trucks is a business. As such, the business owner requires tools that will enable him to know everything he can about his trucks. Many customers don't want to carry laptops out to their trucks each time they want information. They also want something more portable than the dash-mounted display available from Caterpillar. This need gave birth to the Pocket Technician system.

Once the market was defined, we were charged with choosing the platform and creating the product. The ease of use of Palm devices made them the preferred platform, since most people can pick up a Palm device and learn to use it within minutes. The ability of the Palm device to capture data and bring it back to the office for review later was also critical.

Inside the Pocket Technician software
Once we decided to use the Palm OS platform, we realized we had to learn how to write Palm OS applications. Craig Curry, a Senior Electronic Development Engineer at Caterpillar and a veteran in the development of electronic handheld tools, was charged with learning the OS and the development environment. Within a few weeks, Craig was up to speed and creating sample applications to test the techniques he would use for the Pocket Technician software. Craig admits that the hardest part of writing Palm OS applications is fitting everything that we want to show the customer onto a relatively small screen.

When using the Pocket Technician software, the user is presented with a main screen that shows nine different icons for the program features, as seen in Figure C.

FIGURE C

A large picture and a caption represent each of the feature icons.

Selecting the Config icon takes you to the Configuration feature. Configuration allows you to program certain parameters and view others that are read-only. In Figure D, you can see four parameters that can be changed.

FIGURE D

Configuration allows you to program certain parameters.

Tapping on the parameter name or value will bring up a dialog to change the parameter. Pressing the up and down scroll buttons takes you to the other parameters.

Selecting the Status icon from the main screen takes you to the Status feature. Status displays operating information for the engine, as you can see in Figure E.

FIGURE E

Status displays operating information for the engine.

The Scan button puts the feature in scan mode and automatically scrolls through the parameters. Six parameters are shown on the screen here, and tapping the screen will zoom in to four and then three parameters on the screen.

Selecting the Diag icon from the main screen takes you to the Active Diagnostic Code feature. Active Diagnostic Codes are used to indicate when there's a problem or potential problem with the engine. Figure F shows Active Codes with several codes active.

FIGURE F

Understanding Active Codes can help keep your truck engine on the road.

Tapping on any one of the active codes will display more information and advice about that code, as shown in Figure G.