Topology Optimization and Additive Manufacturing Applied to Improve Unmanned Quad-Copter Design

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Maeer's Maharashtra Institute of Technolgoy, Pune (MIT) established in 1983, is today among the top engineering colleges in India. MIT Pune believes in providing its students the right resources and environment so that they can successfully tackle and find solutions to the most challenging engineering problems faced by society today. 

Arnab Chattopadhyay, Vishal Bagthadia, Sanat Munot and Sumod Nandanwar are a group of undergraduate students from MIT working on their final-year project, ‘Topology Optimization of an Unmanned Aerial Vehicle (UAV)’ under the guidance of Mr. Girish S. Barpande, Associate Professor, MIT Pune. In addition to this, the group also worked closely with Mr. Chaitanya Kachare, Associate Professor, Transportation Design from MIT Institute of Design (a sister institute to MIT Pune) who guided them with the additive manufacturing and the aesthetics of the final design. The objective of the team’s project was to design, fabricate and test a Quad-rotor UAV

When designing a UAV, the fact that the vehicle is unmanned removes a lot of design constraints and provides designers with significant freedom. Using topology optimization and removing manufacturing constraints through additive manufacturing can help amplify this design freedom, often results in an exponential increase in the vehicle's performance. 


Altair Inspire in the Design Process
To achieve the best performance possible, the group started off with a simple Unibody (Monocoque) air frame structure based on the design calculations and packaging space of electronics, components and payload. 

Drone-1.png


Using the gathered data, both the systems were modeled accurately in Inspire and the topology optimization was then carried out. Inspire’s easy to use interface and workflow helped the team to achieve better results by enabling them to focus more on the iterations rather than setting up the model. The shape control tools in Inspire also helped the team maintain symmetry about its principle axes which is very crucial while designing multi-rotor UAVs. The team even used Inspire to analyze the post-optimized model very easily and accurately. 

After the optimized designs from both the methodologies were finalized, the model was refined and prepared for manufacturing by removing the sharp contours and stress concentration points using the PolyNURBS tool. The PolyNURBS tool enabled the team to get a solid model closest to the topology optimized results with precision and efficiency. 

Drone-3.png 

Once the drone was redesigned based on the Inspire optimization results, the next step was to manufacture the monocoque design. The team received support from DesignTech Systems Ltd, Pune, a leading CAD/CAM/CAE/PLM, additive manufacturing technologies and solutions provider and value-added reseller for Altair solutions, as well as Stratasys 3D printers. DesignTech Systems supported the team in making the test samples & final designs in ABS M30 from Stratasys. Stratasys extended the team support by 3D printing the parts on their Fortus 450 MC machine at their Experience center in Bangalore. 


Results
After 3D printing of the airframes the team carried out multiple flight tests to test the strength and flight characteristics of the airframes, the flights were very stable and the drone went through multiple crash tests unharmed.

For more information about Altair Inspire, check out these free training videos.