To any manufacturer the results of such product modifications are extensive and in particular in the automotive world where the chain of supply affected has costly time repercussions along its length. Concurrent build of automation systems to a commissioned state is not always possible without a 'final design' component being available. This causes a time delay in component availability, which inevitably compounds down the chain. A supplier to the car industry wanting to achieve a quick turn round needed two robotic routing cells engineered, programmed and built to a 'commissioning ready' state but just from CAD data alone.

The two robotic machining systems required for producing a new instrument panel moulding was a radical change to the expensive and inflexible traditional punching methods. The first systems were programmed conventionally with the tool locations being taught in the 'real world' using a finished component as a guide.

When the next contract for door panels was awarded it was decided to continue with the robotic approach and also to investigate ways to reduce the programming and commissioning process. Even though there were cost and flexibility benefits with the robotic system, the down side was programming the part profiles, which could not be started using conventional techniques, until an approved component became available. This can be many weeks while tooling is being manufactured and several days of robot programming when mouldings finally become available.

Fanuc Robotics engineered two systems with a commissioning deadline coinciding with the availability of door panels. The implication of this being that as the systems were to be engineered concurrently to the door panel tooling, they would need to be built to a final commissioning ready state but without seeing a component.

The complete system was modelled by a simulation package where each cell consisted of one Fanuc M-710i Robot, a multi axis positioner, fixtures and enclosure.

After defining the cell sequence and programme commands the profiles of the panel were recorded together with the robot arm positioning mode at specific points. The simulation created of the cell followed this stage, and unlike conventional system builds methods the robot arm was driven around the cell for the first time in its virtual world. This meant any unreachable locations and collision points identified at this time was safely corrected by altering the programme without leading to any hardware costs.

Because the robot programme was created to the many CAD drawings relating to components in the 'virtual cell' compensation to the cell in the 'real world' was necessary. To enable this a metrology system was used to measure the robot and its environment so finding the nominal car reference frames in the real world referenced to the real robot.

As the simulated robot programmes were developed from the same reference system, all that was needed on the shop floor was to update the reference frames in the robot controller from the nominal to the measured frames. This process successfully aligned the robot programmes from the perfect CAD world to the real installation on the shop floor.

Proof of success came when the first component to be made available to the system was machined using the off-line programme and, without any modifications or intervention and was well within tolerance.

The programming and commissioning process alone saved several weeks over conventional techniques, but the real savings come when there is a need to accommodate a modification from the manufacturer. Firstly there is the flexibility of the robot, which removes the need for new tooling and secondly programming can commence the very moment CAD data is received.

In the drive to meet the requirements of a fast changing market the overriding benefits of this solution is clear. As system partners Micromech Robotics and Fanuc can specify, build and install the right equipment that is simple to programme and operate. Perhaps you are not already using a robot and this has tempted you into the fast lane, if that is so and you would like to find out more about our products and services then call Stirling Morley on 01376 333311