Building the S-10 Electric

Automotive Manufacturing & Production, July, 1997

You would be hard-pressed to distinguish between a conventional S-10 and an electric version. The latter has some different decals. There is some aerodynamic modifications, such as a front air dam and a half-tonneau cover at the box of the cargo box. This brings the coefficient of drag down to 0.34; a conventional S-10 has a Cd of 0.44. But despite the fact that there is a 1,300-lb. battery pack, consisting of 26 batteries, sitting between the frame rails, the electric S-10 looks just like a conventional S-10 from the outside.

If you crawl below the electric vehicle and really know your frames, you'll discover that there is a purpose-built frame. For one thing, there is the battery pack that needs to be handled, which is not the case with a regular S-10. And the big difference is the S-10 Electric is a front-wheel-drive truck (which may make it unique among all light trucks), so a new rear axle had to be developed.

This close affinity between the regular and the electric - there are just 250 parts unique to the S-10 Electric - is by design. That's because the trucks are assembled - for the most part - at the GM Truck Group assembly facility in Shreveport, Louisiana. As Henry C. Thompson, engineering manager, Manufacturing Engineering, GM Advanced Technology Vehicles, puts it, "To make this a viable business, we worked to keep costs down and to keep the whole operation very lean."

The transformation into an electric vehicle occurs in what had been a vacant warehouse that's located one mile by crow fly and three miles by road from the main Shreveport plant. Thompson and his colleagues started refurbishment of the 100,000-[ft.sup.2] building in January, 1996, and were running pilot vehicles by September of that year. The area used for the manufacturing operations measures 68,000 [ft.sup.2].

The routine is that painted cabs, boxes and front-end sheet metal are taken from the lines in the main plant and delivered to the satellite plant by truck in lot sizes of five. Then the truck is processed through 11 workcells. There are 13 people who work in the cells, and 22 in total at the electric vehicle facility. All were volunteers who came over from the main plant.

The major difference between the operations in the two plants is the amount of work that is done by the individuals involved. Those in the S-10 Electric plant may perform as many as 150 tasks in a work cell. The cycle is 53 minutes long, not 53 seconds, as is close to the rate in the mass production facility. The output of the satellite plant is approximately 10 units per day (one-shift operation).

In the satellite plant Bill Szkodzinski, manager-Manufacturing Engineering, GM Advanced Technology Vehicles, points out, "There are no monuments." There are no pits. No solid foundations at the work cells. There is just a single robot, a Fanuc S420i, that's used for glass installation. "It's the only thing in the plant that looks like it could go 60 jobs per hour," Szkodzinski notes. The assemblies are moved around on wheeled carts or by lift trucks. Once the wheels are on, the vehicle is pushed from station to station. Once the truck is completed, it is shipped back to the main plant and put on the line with the conventional S-10s. There, wheel alignment and dynamic vehicle testing are performed. Not only does this mean that the S-10 Electrics get the same type of OEM testing that regular vehicles get, but it also means that they were able to save in excess of $500,000 at the satellite plant by taking advantage of the existing equipment in the main plant.

RELATED ARTICLE: The Future of Automotive Assembly?

Asked to take a look ahead at what vehicle assembly plants and related methods will be like in 20 years' time, when the EVs and hybrids and whatever are, if not the status quo, then at least a large part of it - which means there will be a major effect on what's put together in a plant - J. Robert Thompson, director, Manufacturing, GM Advanced Technology Vehicles, provides the following observations:

* More design for manufacturing and assembly (DFM/DFA) will be used

* Greater use of modules for simplified assembly

* Further increases in ergonomics

* Equipment flexibility will be improved 100-fold

* Vehicles will be based on platforms such that there can be radical changes to the skin and/or interior without affecting the basic platform

* Greater use of both light-weight and recycled materials

* "Break the box assembly." This one, Thompson explains, means not only doors-off assembly, but roof-off assembly, as well. The A-, B- and C-pillars and roof would be attached after the interior is completed. For obvious reasons (think only of the interior fabric or leather seat covers), spot welding wouldn't be the way to make this attachment. So how would it be done? Lasers, perhaps? Thompson says he's not sure: "Well," he notes, "you said to look 20 years out."