Implementation and Testing of a 3-D Hybrid Rapid Prototyping System Capable of Deposition and Machining

Rapid Prototyping (RP), also known as Layered Manufacturing, is a widely used method of manufacturing which has been increasingly applied in the process of design and development of new products. RP's advantages includes being able to produce internal cavities, and being able to deliver and modify prototypes without specialized tooling. New RP technologies add materials than remove materials to produce the prototype part. This simplifies the 3D part producing process to 2D layer adding processes, and permits a part to be produced directly from its computer model. A hybrid Rapid Prototyping system (HRP) developed from existing systems may provide even more flexibility.

Implementation and Testing of a 3-D Hybrid Rapid Prototyping System Capable of Deposition and Machining

Rapid Prototyping (RP), also known as Layered Manufacturing, is a widely used method of manufacturing which has been increasingly applied in the process of design and development of new products. RP's advantages includes being able to produce internal cavities, and being able to deliver and modify prototypes without specialized tooling. New RP technologies add materials than remove materials to produce the prototype part. This simplifies the 3D part producing process to 2D layer adding processes, and permits a part to be produced directly from its computer model. A hybrid Rapid Prototyping system (HRP) developed from existing systems may provide even more flexibility.

Facing COVID-19 pandemic: development of custom-made face mask with rapid prototyping system

Background: COVID-19 is a global pandemic. The virus spreads through respiratory droplets and close contact. Therefore, the availability of personal protective equipment (PPE) for healthcare professionals is essential. 3D printing technology could represent a valid option to ameliorate PPE shortages. Methodology: Custom-made face mask were designed on the basis of facial scan and then 3D-printed. The whole protocol is executed with freeware software and only required a 3D printer. Six healthcare workers wore the device weekly thus expressing a judgment regarding quality of work, respiratory and skin comfort. Results: The estimated total cost of a single mask is approximately 5 USD. The virtual design of a complete mask lasted 68 minutes on average. Most healthcare workers rated comfort as very good. Conclusions: Based on the encouraging results obtained, we can confidently confirm that custom-made masks are novel and useful devices that may be used in the fight against COVID-19.

Adaptive Power-Split Control Design for Marine Hybrid Diesel Powertrain

It is known that mechanical wear and tear of components of large marine engines throughout their lifetime can cause the engine dynamics to alter. Since traditional control systems with fixed parameters cannot deal with this issue, the engine performance may degrade. In this work, we introduce adaptive control algorithms capable of adapting the control system in order to preserve the engine performance once its dynamics deviate from the nominal ones. Particularly, the direct and indirect model reference adaptation mechanisms are studied. In this work, the case of degraded oxygen sensor is investigated as an example of engine components deterioration throughout its lifetime. The controllers are implemented in Simulink, and their performance is evaluated under both nominal and degraded sensor conditions. Specifically, the sensor degradation is imitated by altering its time-delay. In such conditions, adaptive controllers demonstrate a notable improvement in tracking performance compared to the fixed parameters proportional-integral (PI) controller. Finally, the designed controllers are validated on the hybrid marine engine testbed using dSpace rapid prototyping system.