During the design specification phase, an alternative design matrix was made and evaluated based on the following parameters: number of bumpers, shape of bumpers, number of target light sensors, height of beacon light sensor, and finally the floor sensor module location. The 4 conceptual designs were evaluated then, a prototype was constructed that employed three target light sensors, a Beacon light sensor, a Floor Sensor Module for floor color recognition and a three bumper design.

Robotics: Autonomous Devices

Arena with obstacles target lights and navigational light

• Build an autonomous robot that can seek out and extinguish the opponents 2 target lights in under 3 minutes.

• The robot must be able to:

• Sense and remember the floor color.

• Locate and advance upon the navigation light.

• Locate, approach, and knock out the target lights.

• Circumnavigate basic obstacles.

• Speed and efficiency is imperative; the robot will be competing against other units.

Floor Sensor Module Circuit (FSM) – designed for floor color recognition. The reflection of the emitted light from the LED to the floor would differ when on the white side of the arena than the black side of the arena.

Programming• The robot was programmed in C++/C language through the compatible HI-TECH Integrated Development Environment.

Electrical

Conceptual design Autonomous Robots are robots that can perform desired tasks in unstructured environments without continuous human guidance. Many kinds of robots have some degree of autonomy. Different robots can be autonomous in different ways. The current generation of autonomy is particularly desirable in fields such as space exploration, cleaning floors, mowing lawns, and waste water treatment. There are hundreds of applications for autonomous technology in the civilian market, from home and community applications to cameras at intersections. Autonomous robots are a very versatile field. It currently exist for civilian, commercial and research purposes. The objective of the robot project was to create a fully autonomous battle robot able to adapt accordingly to a dynamic environment. The robot’s mission was to navigate, take corrective courses of action in the presence of obstacles, locate, identify and extinguish the “enemy” territory’s target lights before the enemy robot extinguishes the Battle Roach’s home target lights.

Sponsors:National Aeronautics and Space Administration (NASA)NASA Goddard Space Flight Center (GSFC)NASA Goddard Institute for Space Studies (GISS)NASA New York City Research Initiative (NYCRI)Stevens Institute of Technology (SIT)

Contributors:Dr. Siva Thangam, PIProf. Joseph Miles, PISharif Abdelbaky, HSSJusten Garner, UGS

Objectives

Abstract

Applications of Autonomous robots today and in the future

•Unmanned aerial vehicles•Unmanned cars•Autonomous robots on the assembly line•Finding mines in demilitarized zones•Researching alternative fuel sources

Bumper Interrupt Support Board (BIS) – hardware interrupt designed for easy ON/OFF logic. Composed of a 74LS07N Hex Buffer IC, a pull-down resistor, and three micro-switches acting as bumpers.

Stevens Institute of Technology custom-designed PIC microcontroller board. The board has both analog and digital inputs for data acquisition, a voltage divider circuit for the analog light sensors channels, and an Analog to Digital (A/D) Converters for voltage sensing, as well as a motor driver circuit for the two motors used.

The programming could not be done without the flowcharts for they gave the logic in programming the robot.

Program basic routines:• Move Forward• Move Backward• Pivot right• Pivot left• Read light sensor data• Motors off

Main loop flowchart Bumper interrupt support Flowchart

ResultsThe Autonomous robot was able to:• Navigate autonomously through the obstacles in the arena• Use its bumper interrupt system for evasion.• Detect the floor color and where it is using the Floor Sensor Module (FSM)

for color differentiation through color reflectivity thresholds and a Beacon light sensor tower to use the navigation light.

• Detect target lights• The battle robot competition has not taken place

Robot Enemy Target Light Locating/Obstacle Avoidance Subsystem

Goal: Identify the Conceptual Design with the Highest Probability of winning the competition    All Combinations  

   Conceptual

Design 1  Conceptual

Design 2  Conceptual

Design 3  Conceptual

Design 4  Number of Bumpers     2 Bumpers   3 Bumpers   3 Bumpers   3 Bumpers  

Shape of Bumpers    Rounded - Front Split   Rounded-180  

Flying Bumpers w/Strings  

Pointy - Front Split  

Number of Target Light Sensors     1   3: 1Lt, 1Rt, 1 back   1   2: 1Lt, 1Rt  

Height of Beacon Sensor     On Roof   6 in. above roof   6 in. above roof   3 in. above roof  

Floor Sensor Module Photo Resister Location     Front   Rear   Rear   Rear  

Acceptance CriteriaWeight (by %) of Acceptance Criteria (apply last)

Importance of Conceptual Design in meeting Acceptance Criteria

Weighted Score  

Importance of Conceptual Design in meeting Acceptance Criteria

Weighted Score  

Importance of Conceptual Design in meeting Acceptance Criteria

Weighted Score  

Importance of Conceptual Design in meeting Acceptance Criteria

Weighted Score

Teams chose own acceptance criteria                            Doesn't draw down the battery (8 competitions) 20%    10 2  8 1.6  9 1.8  8 1.6 Doesn't confuse the navigation light with target lights 30%    4 1.2  7 2.1  5 1.5  6 1.8 

Minimal Impact on software complexity 5%    8 0.4  6 0.3  8 0.4  7 0.35 Crosses from Friendly to Enemy Territory in 15 seconds 10%    3 0.3  8 0.8  5 0.5  6 0.6 Extinguishes both target lights in 35 seconds 5%    3 0.15  8 0.4  5 0.25  6 0.3 

After crossing over, the sub system detects light 1 and extinguishes it. Then it detects light 2 and extinguishes it. 15%    3 0.45  8 1.2  5 0.75  6 0.9 

Doesn't cross back to friendly territory after crossing into enemy territory 15%    3 0.45  8 1.2  5 0.75  6 0.9 

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Total Percentage = 100% 31 4.95  63 7.6 42 5.95 45 6.45