UAV Design build and fly GDP
Teams
The teams are nominally organised as given below. However, this may be subject change to ensure there is a balance of skills and experience across the teams.
Team A
Andrew Penn
David Holland
Benjamin Nash
Team B
James Hickey
Martin Inglis
Harriet Steynor
Team C
Ricky Bhargava
William Jardim
Martin Casbolt
Nidhil Kapila
Paul Blyth
Andrew Morley
Introduction and objectives
Each team will be issued with a polypropylene fuselage equipped with radio control equipment and rudder / elevator servos. The fuselage is also equipped with an electric motor, propeller and 8.4v power pack. A speed controller can vary the current to the motor to allow full control over thrust settings.
Your task is to design, build and flight-test a wing for this fuselage.
Scenario
The planned application for this UAV is surveillance. The mission profile typically involves a high speed dash to target area followed by low speed flight to allow sensors to capture information. The teams can ignore any payload and fuel/ range issues.
The customer is therefore interested in achieving the greatest possible speed range for this UAV using this fixed fuselage and power plant selection. There are advantages in achieving the slowest possible flight whilst capturing surveillance data but conversely the highest possible flight speed is desirable whilst in transit. You task is therefore to design a wing which can achieve the highest possible speed range.
Deliverables
Apart from the usual GDP report and presentations your task is essentially two-fold:
1) Predict the performance of your wing design and fuselage combination based on analysis, calculations and a limited amount of wind tunnel testing.
2) Carry-out flight testing to compare your predictions with actual performance.
Flight Testing
This will be scheduled late in the second semester. Testing will be carried out using a skilled test pilot who will fly the aircraft and explore the flight envelope under the instructions of the design team. Several flights will be undertaken to fully assess performance.
Low and high speed runs will take place over a 100 metre course using timed runs. Clearly the test must establish performance on the basis of stable, sustained, level flight at low altitude. The course will be aligned with any prevailing wind and testing will go ahead providing there is no more than a mean wind of 8 metres per second. An anemometer will be used to record wind speed during each run.
Design Constraints
You will be allowed to choose between a fairly large range of structural/manufacturing methods and materials. However, you will clearly have to remain within the £240 GDP cost budget. The fuselage/motor and control gear costs approximately £80 so this means that you will have approximately £160 to spend on wing materials.
Your wing must be capable of attachment to the fuselage using the existing pin and bolt design. This means that the wing chord at this point is constrained.
You are limited to a wing span of 2 metres.
You are allowed consider the use of lift modulation devices including spoilers, slots, slats and flaps. There are three spare channels on the receiver to control servos that may be used to actuate high lift devices.
Wind tunnel testing
Two test slots will be made available to you in the RJ Mitchell wind tunnel in the first semester. The first slot will allow you to determine the lift, drag and thrust characteristics of the fuselage/ powerplant at various angles of incidence and wind speed. The second slot will allow you to carry out further testing using wing sections representative of your emerging design.
You will also have fairly extensive access to smaller wind tunnels to help test and select suitable wing sections. You will be able to use the CNC hot wire foam cutter in the aerodynamics lab (Lanchester 2003) to generate tunnel test sections.
Performance prediction and design model
You will need to predict the performance of your design and document this prior to flight trails. Assistance/advice will be given in the use of CFD tools to achieve this. You will be using ESDU VGK full potential code for both 2d section design and 3d wing design. It may be worth familiarising yourselves with this over the summer period.
Assessment
The flight trials will be competitive; the team achieving the highest speed range being deemed the “winner”. However the overall GDP assessment will focus on;
· the elegance of the design,
· the integrity of the design calculations and analysis
· the design rationale.
· analysis and explanation of any differences between prediction and test results.
· quality and structure of report and presentation
Key tasks
The following list of tasks is neither exhaustive nor proscriptive but is intended as an initial check-list.
· Obtain reliable base data on fuselage drag, motor thrust and fuselage lift at various angles of incidence in RJ Mitchell tunnel.
· Identify limits and design targets for speed range.
· Construct design model to establish key design parameters and conduct sensitivity analysis.
· Carry out wind tunnel testing on a range of possible wing sections.
· Tunnel test wing fuselage combination in RJ Mitchell tunnel.
· Select wing section and consider possible high lift devices.
· Consider range of possible materials and manufacturing processes.
· Calculate/estimate wing loads.
· Design/build structural test specimens/test wing structure
· Create wing 3D surface geometry
· Conduct CFD analysis of flight cases.
· Create structural geometry and perform weight estimate.
· Design high lift device actuation mechanisms (if included in design).
· Construct wing (compare actual/predicted weight); consider effect of variance on performance.
· Plan flight test schedule
· Conduct and record flight test data.
· Analyse flight test data and reconcile with performance prediction.
Schedule
The notional schedule is given below. A more detailed schedule with confirmed dates will be issued before the start of the GDP. This will include a series of timetabled meetings between the academics and each team.
JP Scanlan 18/10/2005