Driving Innovation in Product Design and Manufacturing Using 3D Printing
Feedforward’ s spontaneous indicators enable the machine to deliver immediate results and channel them in the right direction when anomalies or mistakes are noticed. Applied to a specific case, feedforward is like an operator that gives direct indication to the system and manually changes the drawer speed to follow the theoretical discharge line.
On the other hand, the PID system allows the machine to correct itself, look to the past to understand if corrective actions are working, directly respond to its operation or predict future trends to be prepared for upcoming events 19.
The brain of METRO continuously monitors its condition and operating modes, such as actual position, applied resistance torque, internal temperature, and so on. The data are evaluated in real time by the PID algorithm into appropriate action commands to, for example, manage the proportional valve which moves the discharge tables or adjust the motor torque control to guarantee seamless contact between METRO and the bed of material.
PID allows the establishment of a continuous loop – monitor, analyze, correct – between METRO and discharge drawers comparing the limestone’ s theoretical position, calculated every second given the starting and target levels defining a descending profile, and the limestone’ s effective position measured by METRO, along the entire cycle.
Figure 4 Typical discharge system PID cycle
An added benefit of the device described above, is that it may be printed on a 3D printer. Engineers can“ print” one part, test it and, based on the test feedback, quickly adjust the digital design and reprint an improved version of the parts using the same additive manufacturing machine. This accelerates the cycle of design, prototyping and production. Adjustments to the production process, as well as to supply chain and distribution logistics, can be calculated and enacted in real time. As a result of this flexible design and development methodology, the original
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Langdon, Morris. Creating Innovation Culture, InnovationLabs White Paper. 2007
- 48- January 2017