This document discusses modifications made to two unmanned aerial vehicle (UAV) platforms, the EAV and XSCAV, used by NASA to test novel control systems. The EAV airframe was modified by adding an aluminum rib structure and avionics box, and replacing the struts with stronger custom-built struts. The avionics systems on both platforms were also updated by adding a second CPU, replacing the power supply, and designing a custom enclosure. Model reference adaptive control (MRAC) simulations were run using MATLAB and results from the updated systems were compared to previous models and tests.

1. Hardware
Implementation of
COTS Avionics System
on Unmanned Aerial
Vehicle Platforms

2. MUHAMMAD USMAN ALI
(12063122-086)
MUHAMMAD FARAN ALI
(12063122-055)

3. I. Introduction
II.EAV Airframe Modifications
III. Avionics Design
IV. EAV System Identification
V. MATLAB Simulation
VI. Reflection Simulation

4. I. Introduction:
 To test novel control systems the National Institute Of
Aeronautics And Space Administration (NASA) operates
two COTS (also known as Commercial Off the Shelf) aerial
platforms in its EAV laboratory. The two platforms
include EAV (Exploration Aerial Vehicle) and XSCAV
(Experimental Sensor Controlled Aerial Vehicle).EAV is the
Cessna 182 while the duties of XSCAV are performed by J3
Piper Cub. To provide low-risk testing of adaptive
controllers EAV will be used but due to its limitations in
limited payload capabilities other platform comes in
mind. To remove this XSCAV is used. There hardware is
updated regularly to provide state of the art power.

5. Cessna 180 and J3 Piper:

6. II.EAV Airframe Modifications:
 To improve its capabilities aluminum rib support
structure and custom avionics box was added but it
resulted in the overweight of system, so to provide high-
g maneuvers in the air the factory struts were replaced
with stronger custom built struts. The stress was easily
distributed between areas of the vehicle.

7. The ribs distribute the stress between the six areas
of the EAV airframe with the heaviest load: the wing
bar area, from which most the lift of the wings is
distributed to the fuselage, the body wing strut
mounts, which also distribute some of the stress
from the lift, and the landing gear, which pass the
impact of hard landings into the belly of the plane.

8. III Avionics Design:
The avionics systems use many state space and transfer
functions to improve real time data processing. In addition
with already using CPU an another CPU was added in the
casket. The former power supply was replaced with a higher
wattage DC/DC power supply. The Unmanned Aerial Vehicle
(UAV) is found to have capabilities very similar to the EAV.
The height of the stack was increased due to the addition of
a second CPU. To address this problem instead of keeping
the stack in vertical they were replaced horizontal. A
custom box provided the requirement for further
improvements. Various specifications were provided for the
box which included its length width and height.

9. Main avionics were chosen in the PC/104 but the main thing
kept in mind was the compatibility so considering this
compatible systems were used with PC/104. Different areas
were kept in mind which included electrical and
mechanical.
To provide repetition of messages to reduce the probability
of errors in transmission in case of signal loss and battery
short circuits there was a need to redesign the actuator
system.

10. IV.EAV System Identification:
The members of this lab carried out a detailed system
identification on flight data using various principles and
laws however a slight error was found but was removed
using new and advanced system. Longitudinal and Lateral
formulas were used for aircraft dynamic model. The result
was run on multiple flight data sets but two results were
obtained. First being the normalized MSE and second being
the generalization score.

11. V. Matlab Simulation:
Model Reference Adaptive Control (MRAC) controller was
used by the NASA Ames Integrated Resilient Aircraft Control
(IRAC) project to study flight tests.

12. VI. Reflection Simulation:
The model is sent to the main software running on the
avionics system which is a real time component based plug
and play architecture. The results are documented

13. SUMMARY:
This paper tells the design modelling and testing process for
two platforms. MRAC Simulation was used new results were
compared with the previous ones. Some improvements were
provided in systems model and hardware which will help us
in the low-risk testing of adaptive controllers under IRAC.