Design, Optimization and Simulation of Quadcopter Frame Using Simulia Platform

INTRODUCTION

Quadcopters, have become extremely prevalent, driven by their low cost and ease of control. Quadcopters have gained interest in surveillance due to huge potential in outdoor applications because of their advantages over regular aerial vehicles. The purpose behind doing this project is to find the optimized frame for quadcopter. That is, to find the cross section, pattern of ribs, length, thickness and many other possible parameters for frame. Also to find the optimized geometry and positions of ribs on the frame. The initial design of Quadcopter is based on existing literature. Initially we’ve used 3DExperience Platform, specifically Part Design and Assembly Design apps to make geometries. Then we’ve used Simulia app of 3DExperience Platform for meshing and analysis of the assembly made. Then we have applied forces at various positions of frame and clamped different features of frame. Then after simulation, the frame which will have maximum strength, i.e. frame which can sustain maximum load and show minimum displacement and minimum stresses was decided to be the final. For the implementation, quadcopter will be 3D Printed, so every detail of frame is very important.

PROBLEM DEFINITION

There are many problems today’s world is facing in the field of transportation listed as follows: 1.     Large amount of labour (man-power): Transportation of goods is not limited to a particular area so large number of skilled manpower is required for transporting parcels. 2.     Cost: To deliver parcels from one place to other, fuel consumption increases thereby increasing air pollution and expenditure. 3.     Traffic: In metropolitan cities, traffic has increased to a deadly level, here quadcopters will act like god’s gift to people facing transportation problem. In designing the frame of quadcopters, one must regard the total weight which will be borne by quadcopter such as the weight of electronics, landing gear, frame, rotor and sensors. For this model, the size was determined firstly so that the type of rotor and propeller used can be calculated in terms of quadcopter ability to carry weight. To obtain the strongest frame possible yet with light weight so as to make it possible to carry weight and stably fly, I sections were made in the frame while keeping in mind the symmetry and the centroid of the frame, also stiffeners are provided.  

NEED OF QUADCOPTER

When we look at the above problems, it seems that these are the everyday challenges of today’s world. To tackle them, quadcopter is a very good solution. In low cost, in can deliver objects, reducing human labor and no issue of increasing traffic. In designing the frame of quadcopters, one must regard the total weight which will be borne by quadcopter such as the weight of electronics, landing gear, frame, rotor and sensors. For this model, the size was determined firstly so that the type of rotor and propeller used can be calculated in terms of quadcopter ability to carry weight. To obtain the strongest frame possible yet with light weight so as to make it possible to carry weight and stably fly, I sections were made in the frame while keeping in mind the symmetry and the centroid of the frame, also stiffeners are provided.  

WHY SIMULATION IS NEEDED

1. Better products: Simulating designs allow us to test and validate different design concepts much earlier in the development process. 2. Cheaper: Simulation allow us to get the design right the first time, so we don’t need have to build physical prototypes of each design iteration. 3. Faster: Simulation is very fast compared to physical testing.  

DESIGN AND SIMULATION

Some of the designs we tried while finding the best frame are shown here. The criteria for the best design was in lightest possible weight of frame, how much more load the frame can sustain giving minimum deflection and lowest Von Mises stress. Here only a few are shown because of space constraint. In Simulia app, we applied same load at same places of different arms, clamping the same features. Then one by one, arms are rejected as per the deflection of results from the arm giving best result. Here we have taken only simple sections for experimentation purpose. Detailed designs of the arms are to be done later.

Steps in the Analysis:

1. Meshing: Finest possible meshing was done for most of the cases, wherever possible. For few cases, where model was so complicated with large size, no. of elements goes beyond 250000, medium quality meshing was done.
2. Choosing Procedure: Static Step Analysis was chosen, with automatic time increment of 1E-5 sec.
3. Applying Material: For 3D Printing, we were going to use ABS (Acrylonitrile Butadiene Styrene), so in Simulia, I created a material ABS, having properties same as the original ABS, like Young’s Modulus 2.9E+9 N/m2, Poisson’s ratio 0.35, density 1060 kg/m3.
4. Restraints: Firstly, I clamped bottom face of central bottom plate, then bottom face of landing gears alternatively for experiments. In actual quadcopter, bottom face of landing gears should have been clamped (fixed), what I did for the final consideration.
5. Interactions: Interactions should be mentioned just like we mention engineering connections in Assembly Design workbench. Here we defined surfaced based contacts of all the arms with top and bottom plates.
6. Loads: Total load to be applied on quadcopter can be mentioned here. Here we applied 80 N and 160 N load at the top central plate for the experiments.
7. Load cases: From the applied loads, which load case is to be considered is defined here.
8. Simulation: Here, first simulation checks are done in 2 steps to check is there any problem in previous steps. Then final simulation is done, after that all the results are displayed automatically.

   CONCLUSION

   By applying the amount of thrust required during different manoeuvres of quadcopter, weight of components attached to frame, gravitational force, resulting deformation (displacement), stress (Von Mises stress) and natural frequency results are studied using Simulia app in 3DExperience platform. The deformation and stress results for different types of analysis are within limit. So it is concluded that the design for quadcopter is safe and up to 160N load can be safely loaded.