Productivity inside the cyber factory

As we move into the 21st century it remains generally true that in most companies the CNC machines remain as individual islands without any real form of communications link. Thus the e-commerce revolution becomes diluted in its path from orders to the real point of manufacture.

For manufacturers fighting to compete globally, the challenge is to embrace e-commerce, deal with decreasing batch sizes and take advantage of both improved machine tool technology and machining techniques. Unless real time communications to the machine tools are improved, set ups may take longer than batch runs - lowering productivity. In addition, operator mobility creates the requirement for more information; minimal manned production raises the need to alert staff when machines have problems; and senior management must have easy access to performance data in order to plan improvements.

To connect the machine tools, a DNC System is normally implemented. However DNC is not enough if an operator is tasked to make a batch of parts; the ability to obtain and transfer the NC program is only one part of the requirement. Additional information is required - eg on tooling, setting instructions, notes from when the job was previously run, etc. Even if these data are provided, the machines can still not be considered as a fully integrated part of the 'cyber factory. If customers are placing orders through the internet and the business system is scheduling the orders, then the information needs to be passed directly to the machine tools - and the productivity of the machines must be retained to meet the demands of the schedule and thus ensure customers' deliveries are maintained.

To solve this problem, Seiki Systems, the software division of Hitachi Seiki UK has launched Seiki FlexLink, a complete package which fully integrates CNC machines into the factory network and CAE environment. The system provides information when things go wrong, plus performance data for management planning. It not only fully integrates the CNC machines to create a true cyber factory and e-commerce environment but also provides the ability to maximise the machine tool's productivity when operating in such an environment. Seiki FlexLink not only enables any Hitachi Seiki machine to be easily integrated into a network without the need to incorporate a PC in the CNC (which could compromise the reliability of the CNC); but is also compatible with Seiki Systems' Networked Manufacturing System which can be applied to any machine tool. This enables the manufacturer to have a single common system to provide the necessary integration for all ONG machines. Essentially four facilities are provided by Seiki FlexLink.

DATA MANAGEMENT
Windows Explorer is used to create a folder for each job, which acts as a single filing area for all related information. The job folder can also be used to point' to other related information held in other parts of the network - eg tool lists in a tool management system, drawings in a CAD system. This provides an easy to use filing environment without the need for any data base (and associated training, costs, etc), and without the need for any duplicate management of data.

OPERATOR INFORMATION The machine operator is presented with a work queue which read directly from the business scheduling system. The work queue is not imported (to eliminate dual management), so the operator always views the current and up to date schedule (which can change rapidly). Upon selecting a job from the queue, the job folder is automatically opened, displaying all available data for the job. Tool lists can be viewed, setting instructions read, NC program transferred etc. Whilst proceeding with the job, data can be automatically collected from the machine and the operator has the additional facility to advise of problems - eg waiting parts, waiting inspection, maintenance required, maintenance in progress, etc.

REMOTE ALARMS
As the machines are being automatically monitored and the operator (if present) is inputting stoppage reasons, remote warnings and remote alarms can be automatically generated - eg audio/visual alarms in the maintenance office for machine failures or maintenance requests; text messages to mobile phones for impending problems such as 'bar feed low' or coolant low'; or actual stoppage reasons; intranet and internet messaging advising problems and requests for support; automatic fax sending to remote support sites etc.

Remote detailed investigation and communications are also available by using standard remote networking facilities such as laptops. The whole objective of the Seiki FlexLink remote alarm system is to draw attention to problems as they happen rather than hold an inquest after the event. This is of particular interest for minimally manned production, large sites and sites that are remote without any engineering support.

DATA ANALYSIS A remote system management screen graphically displays the current status of all machines on the network. This display includes (for each machine) current job; time in current status (eg, waiting inspection); current tools loaded; estimated time to go on job; graphical display of last 24 hours activity; current NC program status (overrides, etc); active alarms; current work queue etc. Also provided is a pie chart analysis of each individual machine performance together with a selectable event trend curve and a graphical report for each completed job including a trend curve for repeating jobs.

For more advanced manufacturers, the shop floor screen can be integrated into a PDM or EDM environment to enable shop floor access to data stored in these high level systems. The shop floor screen can be linked to the CAD system to inhibit the loading of any job when a component is being modified; and to the use of cameras for remote audio/video communications (of particular benefit for large or remote sites where operators need assistance).