Ford Focus on WITNESS Simulation

Ford has been using computer simulation for designing and operating its engine manufacturing facilities since the mid ’80s. WITNESS is available worldwide to all Powertrain users. Today, Ford regards simulation as an indispensable tool in production planning—and one which can provide what the company describes as “an enormous competitive advantage.” 

John Ladbrook, from the Productivity Engineering section at Ford's Powertrain Manufacturing and Plant Engineering Group, has been at the forefront in waging the crusade to incorporate simulation in the manufacturing process. In this article he describes how simulation has developed over the years.

Background

Manufacturing engines involves process engineering, layout engineering and productivity engineering. The key role of simulation lies in the latter and is used to determine, and hopefully maximise, the capacity of the plant using information from the process and layout engineering operations.

By today’s standards, computer power in the '80s was severely limited. The simulation tools that were available to us then, primarily to help validate the manufacturing process, were text-based, with no screen display facility and input controlled by datafiles. They were slow and time-intensive, and one thing that our manufacturing engineers did not have then—just as they don’t have now—was spare time. For the potential of simulation to be realised, more computer power was needed. We had to make simulation more accessible and easier to use.

We developed an early simulation program built around a Fortran-based package from Lanner called Mentor, the intention of which was to enable engineers to build their own models. The big step forward came in 1986 when Lanner introduced the first versions of WITNESS, a faster, more flexible and easier to use package.

By this time, Ford had switched to a Wang computer system, which put a PC on every desk. This offered the possibility of putting simulation across the network. WITNESS was first used in the manufacturing environment for the Zetec engine operations. Lanner helped us with training and implementation.

But I was still searching for a way to get more people to use simulation; I needed something that would do the same job, but quicker, with faster input and response.

I have always believed that simulation should be the first tool in any manufacturing program. Make it easy and quick to use, and everyone will use it. That breakthrough came last year, when we developed a system called FIRST (Fast Interactive Replacement Simulation Tool). Based on WITNESS, the tool uses Excel. Data is input into the spreadsheet and once complete it just requires a touch of a button for the model to be built and executed.

The simulation process could be greatly simplified if we looked at the logic behind the process. I realised that the inputs on which simulation relied could be rationalised; in other words, limit the number of “what if” variables to a sensible minimum. Using existing research information we eliminated much of the input data on, for example, machine breakdowns and the time and frequency of tool changes.

Combined with the use of Visual Basic to implement a better interface between Excel and WITNESS, this enabled us to dramatically cut down the time taken to build and, more importantly, to run simulation models. Today, we can model 4500 hours of machine running time in just 45 minutes. Simulation has thus become a tool any engineer can use, very quickly and with relatively little training.

We now have global licences for Powertrain processes and the enhanced simulation that helps to maximise their operation. All this has coincided with an improvement in the engine manufacturing plant, with better and more compact machines and reduced process times.

Although the basic functions of simulation haven’t changed much, it has become more detailed, responsive and accurate. And it can be quantified. Detailed modeling was undertaken for the V6 engine plant in Cologne, and the changes adopted as a result produced a 3% increase in output of the highly profitable V6 engine. The competitive advantage resulting from simulation is patently enormous.

Perhaps the most exciting work on simulation currently under way is in bringing it up into the “Front End.” Simulation is now being used in plant design, with the development of standard sets of line-building elements, including graphic icons, into which simulation data can be imported. Ford is at the leading-edge in the use of this 'visual factory' system (VisFactory for short) where 3D design layout programs can drive WITNESS—and do it very quickly.

The models are also no longer the exclusive domain of backroom design engineers; once a model has been built, it can be sent off to customer plants. And in that frenetic environment it must be fast and easy to use!

We’ve come a long way since Commodore PETs were laboriously struggling to crunch numbers. With the use of WITNESS integrated into our own processes, running in the background or, as with VisFactory, appearing at the front end, we’ve made simulation an indispensable part of the engine manufacturing process; accurate, detailed and quick and easy to use.