PowerPoint Presentation

Dominick Squillace & Kevin GrignoliELT 2435/13/2013Prof. BiscardiAutonomous Robot

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Code name: OPTIMUS SUBPRIME

DESIGNSCCC Interscholastic RoverAutonomous RC vehicle with embedded systems for collision avoidance navigation and data sampling with the anticipation of data transmission.To be achieved by the use of ultrasonic sonar ping sensors and infrared technology.Engineer circuits for driving bi-directional DC motors. Incorporate sensors and RF technology for data collection and transmission.

Ultrasonic Sonar Ping Sensor

Theory: The ping sensor measures distance using sonar. An ultrasonic pulse is emitted from the unit and distance to target is determined by measuring the time required for the echo to return. Real Life: The accuracy of the ping sensor is severely limited by real world scenarios. Small objects and shallow angles will not produce an echo as the sound waves will not bounce back.

Infrared technology

Frequency formulaDuty cycle formulaConcept: Generate a 38kHz pulse train through an infrared LED and is reflected off of objects and detected by a 38kHz infrared receiver.

(Like shooting a remote control at a wall)

H-Bridge

Theory: The implementation of four switches to control a DC motor in two directions. When two opposite switches are closed, the motor will operate in one direction and in another for the other two switches.

Sensors

DHT11-3 pin Digital Temperature and Humidity SensorMeasures temperature from 0~60CAccuracy of +/- 2CMeasures humidity from 20-90% RH with +/- 5% accuracyBH1750FVI Light Intensity SensorMeasures in lx (Lux meter)Wide range and high resolutionSmall measurement variation of ONLY +/- 20%Little light source dependency

RF Technology ))))))))))))))

NRF2041B 2.4GHz

Up to 1Mbps working speed125 ChannelsHigh anti-jamming GFSK

Intended to send collected data to a remote location. Was not used.

Simulation Multisim!

Original design created in Multisim. Utilized an excessive amount of transistors and arduino pins. Very inefficient use of power.

Simulation Multisim!

Refined H-Bridge design- More efficient use of power and space.

SteeringDriving

Note: able to find curents10

Simulation Multisim!

Built in MultiSim accordingly.

Circuitry verified with oscilloscope.

26 micro second period equates to 38kHz frequency.

Simulation Multisim!

Implementation

If you aint first, youre last ;)

Implementation

Original H-Bridge DesignFirst bread-boarded, tested, and working version. Utilized too much real estate, and high power inefficiency

Refined H-Bridge DesignEmbedded final version that was put into the car.Smaller, more compact, and power efficient.

Road to the top!

Implementation

Improved H-Bridge Circuit Design (steering pictured) Refined H-bridge circuit design, more compact and power efficient. New design was powerful enough for the steering h-bridge to drive the main motor.

Turn n Burn

Ir tech

Pre-manufactured IR sensorLimited Range

Reversed engineeredhomemade versionMore powerGreater range

IR Tech

Incorporated re-engineered design with more IR LEDs and IR receivers.Consumes more power but is easily handled by a single 555 timer.Implemented as a reverse detection sensor.

Prototype

One ping sensor proved to be ineffective in creating a comprehensive field of view. In order to sense adjacent objects, two additional ping sensors were incorporated at 45 degree angles to the original. This addition allowed for a greater field of vision for the vehicle , and a better chance of object detection. THE BUBBLE

Real life: smaller 20

if(Code Red : Code);

By far most difficult part of the project.Required endless amount of parameters for directive processing.Subtle changes in code made huge impacts in testing environment (hallway/corners) Simplicity was key.Less variables allowed for simpler processing and decision making.

Only represents 1/3 of just the driving parameters

PrototypeHit the brakes!!!! .JK, We dont have anyThrough testing, it was evident that simply cutting power to the motor was not enough to stop Optimus Subprime in his tracks. Its massive weight combined with the low coefficient of friction of rubber on freshly cleaned school hallway floors proved to be a hurdle that was not easily jumped.

Using the relay to short out the drive motor leads, created an effective braking system that could easily stop within a reasonable distance as to not collide with objects .most of the time.Effective braking requires a completely shut down H-bridge to prevent the battery from shorting out.

Prototype

Prototype

prototype

Layered... like onions

Prototype

Results

Autonomous robot carDrives by itselfMakes decisionsManeuversData collectionSamples light and temperature X Does not transmit dataX Avoids collisions but has difficulties in some scenarios.Limitations created by sensors available and time/$$$ budget More and/or better sensors needed.

Results

.Oh Snap

In conclusion ..

Referenceswww.Parralax.com www.buildcircuit.comwww.kerrywong.com