Wednesday, January 31, 2007

Ducted fan MAV Prototype @ Indian Institute of Sciencesv(IISc), Bangalore

First of all thanks to Aerospace Engineering Dept, IISc. The project was under progress and is in part sponsorship by Ministry of HRD, Govt. of India. I am thankful to Dr. D. Ghose, Mr. K. N. Krishnanand, Mr. Sharschandra, Mr. Hasan.



19th Jul, 2006: Ducted Fan Proto I: Robotic Aerial Vehicle @ IISc, Bangalore

Ducted Fan Flyer - a MAV under development at IISc, Bangalore
In the extension of mobile robots to three dimension, aerial robots have got a increased attention in recent years and the research on this is something rare in our countries like Nepal, India, etc.

In this respect, the work on MAV is under progress in particular Ducted-fan flyer and Quadrotor concept and i am glad and feel lucky to be a part of the this project under Prof. D. Ghose of Indian Institute of Sciences, Bangalore where I was present for my summer internship (May 8 - July 19, 2006).

The ducted-fan flyer concept consists of a single multi-blade propeller enclosed within a shroud or duct that acts as the main structure of the vehicle; the spinning propeller sucks air into the shroud producing an upward lift. The shroud guides the air vertically down onto a series of airfoil shaped fixed angle stators, which in turn generate lift-forces perpendicular to the propeller turning-axis. The moments generated by these forces provide the anti-torque that is needed to arrest the roll moment of the body (conventional helicopter uses a tail rotor to achieve the same purpose). As the rotor starts spinning at high speed, hovering is achieved as the lift generated by rotor exactly balances the weight of the vehicle.At this instant, if the outlet air is deviated from exact vertical,the vehicle should start cruising.



22nd Dec, 2006: MAV Prototype-2 @ AE, IISc

This date was of great importance as the we (myself, Krishna, Hasan, and Sharsch) made ever first hover into our lab, the Mobile Robotics Laboratory (MRL); Guided, Control, Decisions, and Systems Laboratory (GCDSL); Aerospace Department (AE), Indian Institute of Sciences (IISc).
We were overjoyed in sharing our achievement with our Prof., D. Ghose, who has granted us this project, but he was out of station. I am thankful to you for providing this wonderful environment that made it a success. We took few snaps and videos as for record of that. In the first, you can see the MAV and in the second pic you can see it hovering, and its quite stable, no roll moment at all. Had we not provided the strings, it would have flown-off; and coz we haven't been able to achieve stability completely, it would have ruined our work. The test bench though verry simple was preety much helpful. What all, we need to work on now is stability and electronics control. Unlike the earlier one, we built MAV without duct, still using stators for anti-roll mechanism. We had taken this decision because, we could not get the AXI brushless dc motor from Singapore. So, instead, we though to go ahead for time being without duct, which itself weighed more than 50% of the total vehicle weight in the last design. The idea of using duct was to enhance the lift and safety measures. So, we came to conclusion that if we are able to achieve hover without duct; then obviously we will achieve better control and lift using duct; given an optimised duct is used. In this new prototype, we are still using the stators. The exploration of use of duct, during my last summer-project suration has been of quite help. In this new proto, we saw that it not only provided roll-moment arrest but also stability. The total weight of the vehicle is only 36 gram. Krishna sir's help, and interaction was also a great reason for this successful achievement. With this, we fell we have completed 1st phase of our project, and we should move ahead with controls for which we will soon decide the components required and place order for those.

My MAV prototype-II video
-------------------------
The experiment was successfully carried out IISc, Bangalore. We achieved the first phase of the project on aerial robot.





31st Jan, 2007: Paper ppt at CASST'07


Conference on Advances in Space and Science Technology 2007(CASST’07) was held at Indian Institute of Science, Bangalore between 29th-31st January, 2007 and our paper "Ducted fan aerial flyer – an overview and roll moment control" had got selected for the international conference. I did deliver the presentation with a good appreciation and everyone were more interested when they saw the video of out MAV proto - 2.

Monday, January 29, 2007

Ducted Fan Flyer - Design Overview and Roll Moment Control

Karna, Amit & Kaipa, Krishnanand & Ghose, Debasish. (2007). Ducted Fan Flyer - Design Overview and Roll Moment Control. 10.13140/RG.2.2.15523.04646.

This paper presents the preliminary design phases of a ducted-fan micro air vehicle (MAV). This vehicle concept consists of a single multi-blade propeller enclosed within a shroud/duct that acts as the main structure of the vehicle; the spinning propeller sucks air into the shroud producing an upward lift. The shroud guides the air vertically down onto a series of airfoil shaped xed angle stators, which in turn generate lift-forces in a direction perpendicular to, and offset from, the rotor turning-axis. The moments generated by these forces provide the anti-torque that is needed to arrest the roll moment of the body (conventional helicopter uses a tail rotor to achieve the same purpose). As the rotor starts spinning at high speed, hovering is achieved as the lift generated by rotor balances the weight of the vehicle. Vehicle cruising may be achieved, if the outlet air is deviated from exact vertical. In particular, we have built a small prototype of the vehicle and successfully tested the roll moment stabilization in our experiments.

Link