Automated Bridge ScourInspection

FSU/FAMU College of EngineeringTeam 7

Concept Design Review

12/1/2010

Revised System

Vertical Motion

Design Updates / Improvements- Concepts considered- Selection criteria - Risks associated with selection

Schedule / Budget Updates- Analysis time exceeded- Fabrication time overestimated- Proposed equipment within budgeted amount

Vertical Motion

Analysis Method / Assumptions - Operating parameters for DC Motor

- Critical Operation Point- Gearing for adequate ascent/descent speed

Analysis Results- Minimum load torque: 6.5 N*m - 5:1 gear reduction ratio

- Adequate speed: 20 cm/sec- Sufficient output torque: 32 N*m

Vertical Motion

Revised Specification- System weight inflated 10%: 44 lbs.- Motor load under 80%

Proposed Equipment- Maxon Motors RE 35 Brushed DC Motor

- 24V Operation- Maxon Motors 32 HP Planetary Gearhead

- 28:1 Reduction ratio- Combined Cost: $ 468.00

Vertical Motor Performance

Circumferential Motion Design Updates / Improvements- Concepts considered- Selection criteria - Risks associated with selection

Schedule / Budget Updates- Analysis time overestimated- Fabrication time overestimated- Proposed motor within budget amount- Guiderail cost pending

Circumferential Motion

Analysis Method / Assumptions - Operation at low speed, low displacement

- Low drag- Focus on precision positioning

Analysis Results- 12 V DC Motor- Minimum 200 oz-in stall torque

Circumferential Motion

Proposed Equipment- Pololu 12V 131:1 DC Gearmotor- Combined 64 CPR Encoder- Cost: $ 40.00

SONAR TiltDesign Updates- Maintain previous design - Lower priority- Low risk

Schedule / Budget Updates- Analysis and specification pending- Budget on par

Design Structure

•Design Updates and Improvements

•Circular Guide Rail

•Component Housing

•Localization

•Risks

Design Updatesand Improvements

•Circular Guide Rail

•Bishop-Wisecarver

•Single Edged PRT

•24” Diameter

•11.5 lbs

•Custom Hinge

•Component Housings

•Locker 2 by Witz

•Size

•Pressure

•Localization

•Motor + Encoder

•Accuracy

Risks

•Ring Design•Custom

•Waterproof•Exit Holes

•Encoder Accuracy

Power Old Design Use 2 separate battery sources - DC Motors, Motor Controller - AGM battery - Microcontroller, Sensors - NiMH Better efficiency, less power loss

The New Design - Motor Driver outputs 5V for

Microcontroller,Sonar,servo. Eliminates 2nd battery - Use 1 LiFePO4 or SLA Battery to power

everything

Block Design for Powering Components

- Motor Driver has a feature that can power the DC motors and also some low power

components.

Sabertooth dual 25A motor driver

Controls 2 Brushed DC Motors independently

5V Output Terminal for Microcontroller Power

Lithium protection mode

Built-in Overcurrent & Thermal Protection

Screw-in Terminals for Easy,Secure Connections

Continuous Output per channel

25 Amps

Peak Output per channel

50 Amps

Nominal input Voltage

6-24 Volts

Max Voltage 30 Volts

Size 2.6''x3.2''x0.8''

DC motors

Vertical motion motor

- Nominal Voltage 24V

- Starting Current 41A

- Cont. Current 3.36A

Circumferential motion motor

- 12V ~300mA

Battery

- Weight and Cost are issues

- Lead Acid vs Lithium Polymer

1. Sealed Lead Acid Battery

- Cheaper, but heavier

2. Polymer LiFePo4 Battery

- More expensive, but lighter

Technical Risks - hook up battery to motor driver reverse polarity.

This will damage and void the driver!! Add a diode to prevent this. Product is expensive ~$125

- Motor overheating,

The motor driver peaks at 50Amps and has over-current protection built-in. DC motors are within the motor driver's capabilities...6V-24V

continuous run < 25Amps. Starting run < 50Amps

The Next Step..

- Choose battery type and capacity Ah

- Choose/Purchase DC Motors and Motor Controller

- Purchase a Battery for testing purposes

- More detailed design to integrate into system (wiring, positioning electronics in casing, protection, i.e.)

MicrocontrollerBeagle Board

• $149

• ARM ® Cortex TM A8 MHz @ 1 GHz

• LPDDR RAM 512MB

• SD Card Expansion

• 3D graphics accelerator

• 5 Volts

• 16 I/O IC2 ports

• RS-232 Port

• Large active community

Autonomous Programming

• Language - C++

• Computer Environments - Eclipse - Netbeans

• Beagle Board Packages - Bash task - Nativ-sdk - gdb - samba

Autonomous Programming

• 3 Modules - Vertical Movement - Circumference Movement - Sonar Servo Movement

• Outputs - Motor Controller - Servo

• Inputs - Encoders - Sonar

Current Progress

- Preliminary pseudo code finished

- Detailed information on I/0 Communication

- Write Detailed pseudo code

- Begin programming using Eclipse and/or Netbeans

Technical Risk

• Inefficient amount of I/O pins

• IC2 1.8V Tolerance

• Microcontroller shortage

SONAR• Old Design:

• Test multiple sensors

• Use Fish Finder transducers

• Lower costs

• Compatibility issues w/ microcontroller

• Time Constraints

• New Plan:

• Only test 1 or 2 sensors

• SONAR altimeters

• Higher costs

• Connect directly to microcontroller via RS-232

Benthos PSA-916

Frequency: 200 kHz

Beam Width: 14 degrees conical

Range: 0.8 m – 100 m

Output: RS-232 (digital)

0 – 5 VDC (analog)

Resolution: RS-232: 1 cm

Analog: 2.5 cm

Power: 6 – 24 VDC; 100mA @ 6V

Dimensions: 2.25” Diameter X 9.38” Long

Weight: 1.4 lb (air); 0.8 lb (water)

Kongsberg 1007 Series

Frequency: 675 kHz

Beam Width: 2.5 degrees nominal

Range: 0.61 m – 30.48 m

Output: RS-232; 9600 baud rate

Resolution: 2.4 mm

Power: 22 – 26 VDC; 250mA

Dimensions: 3.49” Diameter X 7.75” Long

Weight: 5.2 lb (air); 2.4 lb (water)

Tritech PA500

Frequency: 500 kHz

Beam Width: 6 degrees conical

Range: 0.3 m – 50 m

Output: RS-232; 9600 baud rate

Resolution: RS-232: 1 mm

Analog: 0.025%

Power: 24 VDC @ 80 mA; 12 VDC @ 160 mA

Dimensions: 1.85” Diameter X 6.30” Long

Weight: 2.43 lb (air); 1.76 lb (water)

Risks

• Physical Damage to sensor

– O-ring

– Abrasion from sediment

• Operation Angle

• Weak Signal Received

• Obstacles

Budget

Schedule