DESIGN CENTER

A lot of literature are available on how to design a fixed wing aircraft. Most of the tools, like Advanced aircraft analysis, are based on the design theory as described by Roskam, Raymer etc. These traditional methodologies on fixed wing aircrafts have evolved over several decades but are not suitable for low Reynolds number flow regimes, typical for most small UAVs. As a consequence, these design methods result in aerodynamic and performance characteristics that can be skewed and misleading for small UAV applications.

The design center at MAV unit has been established to cater to the design needs of fixed wing Mini and Micro UAVs and flapping wing MAVs. Apart from the low Reynolds number flow problems, the highly 3D flows due to low aspect ratio wing and propeller dominated flow over the wing makes the aerodynamic characterization a challenging one. The design team uses commercial codes like ANSYS-Fluent and open source tools like XFLR5 to obtain the aerodynamic characteristics and AVL, Tornado for obtaining the stability derivatives.

This facility houses high end work stations for the CAD and CAE needs, drawing release and rapid prototyping using 3D printing technology for a quick assessment of the design. This machine can also be used for making wind tunnel models as well as flight worthy models if designed properly. The foam cutting machine enables the unit to develop the flight model in no time and less cost. This lab houses a software tools and equipment that allow researchers to quickly build and modify MAVs. The lab even has a laser cutter with the ability to cut soft materials like Balsa wood, Cardboard, Acrylic etc.

Objectives

Design, analysis and development of fixed and flapping wing MAVs.
Implementation of open source design tools for conceptual and detailed design.
High fidelity computational analysis.
Advanced Prototype fabrication.

Specifications

RPT (Rapid Prototyping)

The fused deposition modeling (FDM) process constructs three-dimensional objects from 3D CAD data. The process starts with importing the STL file of the model into a pre-processing software, which is then oriented and mathematically slices into horizontal layers varying from ± 0.127 – 0.254 mm thickness. After reviewing the path data and generating the tool path, the data is sent to the FDM machine.

Figure 1:FDM process

Machine Specification
Type	Fused Deposition Modelling (FDM)
Materials used	ABS-M30 (Black, Blue, Grey, Red and White) and Nylon( Phase 2)
Build envelope	355 x 254 x 254mm
Layer thickness	From 0.127 mm to 0.330 mm
Support structure	Soluble SR 30
Achievable accuracy	±0.127 mm or ±0.0015 mm/mm
Power requirements	230 VAC, 50/60 Hz, 3 phase, 16 A/Phase

		Figure 2: Laser Cutting Machine
Laser type	Co2 DC Glass Laser Tube
Wave Length	10.6 um
Supply Voltage	AC 220 V + 10%
Re-positioning Accuracy	0.1 mm
Cutting Speed	0~30000 mm / min
Engraving Speed	0~64000 mm / min
Cooling Method	Water Cooled
Work Environment	Temp: 0 c ~ 45 c. Humidity: 5% ~ 95%
Acceleration Speed	1 G
Working Area	600×400 mm
Graphic File support	PLT, CDR, AI, DWG, DXF, DST, BMP, JPEG, TIFF, GIF, PCX, etc.

		Figure 3: Foam Cutting Machine
Effective horizontal travel	380 mm
Effective vertical travel	225 mm
Axis	4 Independent Axis (Will Cut Tapered Wings)
Electronics	4 Axis Pulse and Direction on Printer Port
Motors	NEMA23 2.8A 3.3V
Power	110 V 200W
Cutting speed	Software Dependent – up to 20”/min
Resolution	4800 Steps per Inch