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Firefighting Robot

Design Presentation II

By Sarah Clark, Ben Fontaine, and Danny Gersick

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Problem Statement

Create Robot for the Trinity College Fire-Fighting Robot Contest

Put out Fires, which are candles, in a simulated apartment
Able to respond to a 3.8 kHz starting frequency signal
Avoid Dog Obstacle
Respond to its surroundings

Avoid Obstacles
Traverse Over Rugs

Time based (3-5 minutes depending on level)
Save the Baby (Level 3)

Find Correct Cradle
Deliver to Safe Zone

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Specifications and Constraints on Design

Robot Overall Dimensions

Base: 31 x 31 cm, Height: 27 cm
Baby pickup device

Never exceed 41 cm, and must be fully retracted to within the required dimensions at start.
The cradle with baby will be placed 82mm off the floor.

Arena dimensions

Apartment Dimensions: 8ft x 8ft
Hallway and Doorway widths: 46 cm

Control Panel

Must be attached to Handle on top of the robot

All of the rules and dimensions we know so far are from last year, we will have to wait for an update for the coming competitions rules, but they will probably not change by much.

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Arenas

Level 2:

Level 1: Level 2: Configuration A Level 2: Configuration B

Level 2: Configuration D Allocated Rug Locations:

Shaded locations are rug areas, but rugs will not be in all these locations.

Level 2: Configuration C

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Our Solution (UPDATE)

Rectangular Base, 2 Front Wheel Drive DC Motors with Wheels, 2 Rear Casters. Battery Powered
Fire Extinguisher

CO2
Valve

“Spatula” Baby Carrying Device
Micro Controllers

Raspberry Pi
Arduinos

Sensors

UltraSonic Sensor (Wall Sensor)
IR Flame Sensor
IR Line Sensor to sense the doorways

Handle

Transporting the Robot
Control Panel

Rough Solidworks Rendering of Base

Ben

We will be using a rectangular base with two wheels controlled by DC Motors and two Casters to maintain balance. To put out the fires we will be using CO2 Canisters of 16 grams and a Valve to control the output so that we can put out multiple fires. To carry the baby, we will use a Spatula like Carrying Device. This will allow the robot to carry the cradle to the safe zone. We’ve decided to use a Master/Slave method with the Raspberry Pi as the Master and two Arduinos. One Arduino will be in charge of Extinguishing Sub-System and the sensors, while the other will control the DC Motors. The line sensor will be near the bottom as much as possible because of the close range. The spring is to make sure that the line sensor isn’t badly damaged or dislodged.

We also may need some buck converters.

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Drive System

Used the Uxcell 12 V 220 RPM motor with wheel set.

Got a average speed of about 17.44 in/s.

The current design will use aluminum plates and look a bit neater later on.

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Drive System Code

I put the code in functions for specific movements. The pictures below contain the functions in the code.

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Rug Considerations

Line sensors tend to need to be close to the line on the floor to be able to read it. This is a problem since the rug which can be 10 mm tall, is taller than the range of the line sensor.

HiLetgo IR Infrared Obstacle Avoidance Sensor Module for Arduino

The effective distance range of 2 ~ 30cm, the working voltage of 3.3V- 5V.

Board size: 3.2 cm by 1.4 cm

Weight: 0.81 ounces

Can be widely used in robot obstacle avoidance, obstacle avoidance car, line count, and black and white line tracking and so on.

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Fire Extinguisher

Flame Detection
Extinguishing method

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Flame Sensor

IR Spectrum
+/- 60 deg (Left to Right)
Analog Signal (arrow)

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Flame Sensor Code

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Extinguisher

CO2
Valve
Coupler

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Extinguisher Code

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Cradle

The Cradle will only be in Level 3
Robot must find and carry baby back to start before putting out candles
The Cradle containing baby will be 8.2 cm above floor
Cradle base will have patterns or LED on it depending on team choice.

Pattern method will increase score by 150 points, but may not have the time.

Cradle and base

Cradle Front

Huskylens

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Concept Picture of forklift/spatula motion

1: Retracted:

One gear connected to motor turns gear connected to rod.

Rod

Cradle

2: Extend:

Motor activated. Gears turn.

3: Get cradle:

Motor activated. Gears turn. But in opposite direction so it lifts.

Part 4: Carry cradle to start position. Lower arm so it will slide off. Then fully retract arm after dropping it off.

Software Chart

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Baby/Cradle Saving Device

Plan to use a servo motor to move the forklift parts.
Plan on using the Servo 6001HB on pololu.
Going to use it on the arms to turn the arms.

May need to use another servo motor to control forklift part itself depending on room available in robot, to get it with starting dimensions.

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Score Keeping

In this competition lowest score wins. You get your total final score (TFS) by adding the lowest operating score in each level. TFS = LS1 + LS2 + LS3.

Level 1 and 2:

You can improve your score by completing additional tasks like the operating modes.
The judges will record for each trail, the operating modes, the actual time (AT), room factor (RF), and the penalty points (PP).
After the trial is completed, the judges calculate the Operating Score (OS). To get it:

Multiply all of the active Operating Mode (OM) values together to find the mode factor (MF). If no operating modes apply then MF = 1.
Add all the PP points to the AT to get Time Score (TS). TS = AT + PP
OS = TS x RF x MF

In order to compete in the next level you have to have a

successful run in the previous level.

Sarah

In this competition the one with the lowest score wins. The Total Final Score is the lowest score of each level combined. In Level 1 and 2 you get your scores by taking the time it took to extinguish the fires, called the actual time, then we add up all the penalty points to the actual time, to get the Time Score. Then we get our mode factor by multiplying the factors for all the operating modes we used. And we get our room factor by taking how many rooms the robot searched. We multiply the Time Score, with the room factor, and mode factor to get our score for that run.

If you fail to complete the trial within the time limit you get a score of 600.

Other notes:

The TFS is an addition of the lowest OS of level 1, the lowest OS of level 2, and the lowest OS of level 3.

The AT is the time the robot took from activation to flame disappearance. The max AT for a successful trial is 300, or at least for level 1. They max AT will change depending on level since it is set around the time limits. Level 1 is 3 minutes, level 2 is 4 minutes, and level 3 is 5 minutes. However if the robot doesn’t extinguish the flame within the limit, the judge will assign a an AT = 600. The AT doesn’t count the time it takes to get back to start. However all robots in return trip mode must return to the start circle within 2 minutes after extinguishing the candle.

RF pertains to the number of rooms searched before it finds the candle. If a robot enters the room with the candle, but does not extinguish it, that still counts. Scores for RF are:

One room searched: RF = 1 2nd room searched: RF = 0.85

3rd room searched: RF = 0.50 4th room searched: RF = 0.35

PP will be added to the AT. Touching the candle or it’s base while lit will have 50 PP for each time. Continuous Wall Contact, is when a robot slides along a wall. The robot will have 1 point added to its AT for each 2cm of wall. Touching is allowed but it cannot slide. There is no penalty for touching or sliding along the wall on the return trip. Kicking the Dog, which is when you move the dog more than 1 cm will have 50 PP added to its AT score.

Operating Modes Info:

We are in the Senior (Sr) Division. We get no extra points when the mode is required.

In the furniture mode, the robot if needed has to go around the furniture without touching it in order to get this OM.

In the return trip mode, the robot must return to its starting location after extinguishing the flame. The robot must stop with any part of its chassis within the 30 cm white start circle.

In arbitrary start, the robot will be placed by the judges in a arbitrary position. It will be placed in any room that does not have the candle, determined by the toss of a die. It may be facing a wall but will not be trapped by furniture. There is no start circle, and the starting room doesn’t count as a searched room for the room factor.

The Candle Location mode is to find the candle without a candle circle.

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Score Keeping

In Level 3, scoring is a bit different. An incomplete run run will receive a score of OS = 600.

There is no Room Factor (RF)
There is a 300 second (5 min) time limit to rescue the baby and put out all the candles.
There is no requirement to return to start, except when to return the baby.

You get an initial score based on table below.
Then if the robot uses the ramped hallway it will subtract 25 points from the score.
If the robot rescues the baby, the multiplier, TIME.MULT = (Measured time to rescue baby)/300 is computed. If baby was not rescued the multiplier is 1.
The OS = (Initial Score) x TIME.MULT.

To clarify, to rescue the baby you must find it, and return it to the start point.

Sarah

In level 3, you get an initial score based on the table here, if you used the ramp you subtract 25 points. If the robot successfully rescued the baby we take the time measured to do that, and divide that by 300. We take the initial score and multiply it with the rescue time calculation to get our score for the level.

Other notes:

In level 3 there will be two arenas separated by a hallway. The robot will start in arena A. The baby will be placed in arena B. In order to complete the level, you must (1) find and get the baby, (2) transport the baby back to the start position, (3) leave the baby at start position, (4) and extinguish all the candles.

Initially there will be one lit candle in Arena B. Two additional candles, initially not lit, will be placed in Arena A; these candles may be in the same room or in different rooms. One of the Arena A candles will be lit 90 seconds after the robot begins operation. The second will be lit 120 seconds after the robot begins operation.

The robot must pick up the baby and bring it back to the chosen safe zone. The time needed to complete the rescue task (the Actual Time for the run) is recorded. Robots that fail to rescue the baby may receive credit for other completed tasks.

The table in this slide only factors in the initial score not the ramped hallway points or the TIME.MULT.

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Questions