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Team A3: BikeBuddy

Jason Lu, Jack Wang, Johnny Tian

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Use Case & Design Requirements

Bike Safety Hub

  • Blind Spot Detection
    • Warn if car or large object is within 10-meter range
  • Collision Alerts
    • Relative speed of car behind is >= 15 mph
    • Near insufficient distance left to brake before hitting car in front1
  • Turn signals
    • Capable of self-canceling when making 90 deg. Turns
  • Centralized Warning Display
    • Flash red on section of display if having potential of being hit

Category

Metrics

Cost

<= $200 Market Price

Power Consumption

>= 2 hrs endurance

Detection Range

>= 10 m

Uptime

>= 99.999%

Confusion Matrix

<= 40% False Negatives

<= 30% False Positives

Ruggedness

IPX4

Difficulty of Installation

Easy (user survey)

1Equation for stopping distance from AASHTO “Guide for the development of bicycle facilities”, 4th ed.

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Solution Approach

Cars Can’t See Bikers vs Bikers Can’t See Cars

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Why Radar?

  • All-weather operation
  • No direct line of sight requirements
  • Speed measurement
  • Direct serial output (K-LD7)

Radar

  • Susceptible to interference from atmospheric conditions
  • Direct line of sight required

Lidar

  • Short range
  • Can be affected by ambient conditions

Ultrasonic

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Other Possible Benefits

Reduce healthcare, repair costs due to less rate of collisions

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Economic

Making biking safer

More people biking

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Public Health

Reduce collision rates between cyclists and vehicles

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Safety

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System Specification

  • K-LD7 Radar
  • RPi 4
  • Hosyond IPS 5 INCH LCD
  • Hyunduo 5V LED CHIP light bulb
  • Anker 337 power bank
  • Button
  • Rapid prototyped waterproof enclosure

https://rfbeam.ch/wp-content/uploads/2022/11/K-LD7-EVAL-1024x1024.png

https://m.media-amazon.com/images/I/61e-o+8K9HL._SL1500_.jpg

https://m.media-amazon.com/images/I/51rXQqJtTxL._AC_SL1500_.jpg

https://m.media-amazon.com/images/I/71PrFibLvLL._AC_SL1200_.jpg

https://www.sparkfun.com/products/15447

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(Based off the example block diagram in the handout)

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Turn Signal Schematics

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Turn Signal

led blinking

switch activation

handlebar position sensing

self cancellation

UI

hello world GUI

design mockup

UI implementation

sensor integration

Exterior Case

bike attachments

fitment check

waterproof check

Radar

radar basic bring up

raw data processing

tuning for BSM*, RCW*, FCW*

*BSM - Blind Spot Monitoring, RCW - Rear Collision Warning, FCW - Forward Collision Warning

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Testing, Verification and Metrics

Metric

Test Plan

Pass Metric

Mitigation Plan

Uptime

  • Record time that radars respond to data queries on RPi, divide by total application runtime

>= 99.999% uptime

  • Analyze why system is not available and address accordingly - e.g., if wiring is loose, tighten them

Confusion Matrix

  • Static testing - Record radar performance with and without objects in front in a controlled environment
  • Real world testing - Record video, manually count both types

<= 40% False Negatives

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<= 30% False Positives

  • Try with different enclosure materials and radome configurations
  • Tune radar parameters (max speed, distance, frequency)
  • Switch to other method (LIDAR)

Power Consumption

  • Measure average current draw using ammeter and extrapolate total time
  • Record the running time of the system under normal use

Endurance time >= 2 hrs

  • Measure current draw of each component to identify excess usage
  • Use a lower power device that still meets perf. need
  • Increase battery size

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Testing, Verification and Metrics

Metric

Test Plan

Pass Metric

Mitigation Plan

Detection Range

  • Static testing - Verify radar on bike can see parked car beyond 10 m in a controlled environment
  • Real world testing - Record both display and behind bike, manually analyze distance of vehicle when alert is triggered

Car >= 10 m detected

  • Try with different enclosure materials and radome configurations
  • Tune radar parameters (max speed, distance, frequency)
  • Switch to other method (LIDAR)

Ruggedness

  • Test with IPX4 test protocol
  • Test functionality of system in case by riding around in poor conditions and verifying functionality still works

Passes IPX4 test, functionality unimpeded by case

  • Identify points of water entry and seal
  • Verify all wiring is tight and undamaged
  • Verify radome to sensor distance is correct

Difficulty of installation

  • Ask 5+ bike riders to try the product and gather their opinions

Rated “easy” on rating scale

  • Survey what people want and redesign if possible

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Project

Management

Jack:

  • Radar Bring up & Tuning

Jason:

  • RPi software/UI

Johnny:

  • Turn signals
  • Enclosure fabrication
  • Part Installation

Spring break

Start of finals