RMP: Rapid Manufacturing Platform

Jean-Yves Hascoët, professor at GeM, head of the Additive Manufacturing and Biofabrication Platform and lead of the Additive Manufacturing work package within the Joint Laboratory of Marine Technology: “The backbone of the platform is playing with trajectories in space”,

Several manufacturing processes

The platform brings together several manufacturing processes: additive manufacturing, machining, forming, welding and bioprinting.

Biofabrication

Bioprinting consists of printing living tissue using 3D printing approaches. The Centrale Nantes team, led by Jean-Yves Hascoët, works closely with the team of Prof. Gilles Blancho, director of ITUN (Institute of Transplantation, Urology and Nephrology) at Nantes University Hospital and of IHU CESTI, as well as with the RMES team.
Engineering and biology come together to determine the needle diameter to use, the pressure to apply and the viscosity to achieve. Today, the team has mastered both the material and the process. The long-term goal is to explore the field of organ grafting and transplantation. To avoid rejection by the patient, the idea is ultimately to be able to (re)build an organ or parts of an organ from the patient’s own stem cells.
The team’s next challenge: vascularising the created material.

Powder bed additive manufacturing

This laser powder bed additive manufacturing machine produces finer parts, both in dimensions and in surface finish, making it possible to work at the micron scale.
The machine manufactures parts for all sectors: aeronautics, space, shipbuilding, automotive, rail and also the medical field.
It uses powders placed in a tray; a laser then melts the powder required for the part. Unmelted powder is set aside and reused.

3D printing for the medical field

Step by step, additive manufacturing at Centrale Nantes has also turned towards the medical field. The team started by printing knee and hip prostheses and is currently working on many projects:

A hand prosthesis with UTC and Saint-Antoine Hospital in Paris, aiming to build metal phalanges from titanium powder
Surgical guides for training and assisting surgeons
A project to repair large bone defects combining stem cells and custom implants

New equipment is being acquired/installed as part of the State-Region Planning Contract (CPER).

Hybrid manufacturing

This cell houses a high-capacity robot able to carry 500 kg at 3 metres. This exceptional machine enables hybrid manufacturing of large parts. It can combine several processes: wire-based (aluminium, titanium, steel…) melted with an electric arc (WAM), or powder-based (LMD). Two heads can deposit powder 2.5 mm or 4 mm thick.
The machine can also finish parts (machining and polishing) whose surface finish may not be satisfactory.

Calculation and simulation

Design and calculation through applications in the field of:

Mechanics
Fluid mechanics with particle spraying
Bio-manufacturing with material mixing

Inspection, measurement and structures

The platform has several inspection instruments:

A precision laser (accurate to the micron) able to scan an existing part to capture its “skin”, used to inspect parts produced by additive manufacturing.
A scanning electron microscope (60,000× magnification) used to understand the behaviour of powders and the structure of manufactured parts.
A 3D microscope used to capture the surface topology of an object

Parallel kinematic machine

This prototype machine moves a mass of 150 kg, instead of several tonnes on other machines, by using the five axes of the kinematic chain. It is used for machining, forming and welding. It helps manufacturers who want to know the forces and power required to machine a part, test and compare tools, and determine their service life. It supports thinking about how to manufacture a part as quickly as possible while meeting the specifications.

Numerical controls

Centrale Nantes has developed an “open” numerical control, called “Open CN”, which lets users define the algorithmic part themselves and modify manufacturing in real time. Industrial clients of this incremental forming platform can choose between the equipment’s different numerical controls: NUM (French), FIDIA (Italian) and Siemens (German) for their projects and/or tests.