Stamp Bug Project

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Stamp Bug Project

• Jack Harris

Second Year Electronic and Electrical Engineering
Student
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The Stamp Bug Project An Introduction

• Part of the Engineering Project Management
  module.
• 4 groups per company
• 4 people per group
• Each group is given a different task to complete
• Darts
• Gymnastics
• Orienteering
• Basketball
• Competing against 3 other companies in a Stamp
  Bug Olympiad in the spring

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The Stamp Bug

• Robotic Insect
• Made by a company called Parallax
• Unmodified bug consists of
• 6 plastic legs
• Servos
• PCB body
• Power supply
• Electronics
• Feelers (switches on the front of the bug)
• Current additions to the bug include a breadboard
  with the hardware for the RF receiver and an
  extra battery pack.

The Stamp Bug
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Our Task - Orienteering
For illustration purposes only

• Objective
• To collect a token and return it to the start in
  the shortest time.
• Rules
• You can use a remote control.
• The course is unknown before the Olympiad.
• The team provides the token and its largest
  dimension must be between 10mm and 30mm.
• You must drop the token once over the start line.
• You can lift obstacles up.

Token pick up area
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How Our Bug Will Work

• Wireless RF communications between the remote
  control and the bug.
• Remote control made from an old Nintendo
  controller.
• Software altered so that the bug can turn around,
  stop, pick up and drop the token.
• Token will is likely to be paperclip.
• Use of electromagnetic system to pick token up.

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Prototype Electromagnet

• Core is made from cast iron.
• Connected in series with a 1O resistor to avoid a
  short circuit.
• Approximately 160mm10mm10mm
• Will be powered by a 6V power supply.

The prototype electromagnet
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Strength of Magnet Will it pick up a paperclip?

• Currently the magnet is only strong enough to
  pick a paperclip up if it makes contact with the
  paperclip.
• The magnet will need to be made stronger or a
  mechanical solution will need to be found if we
  are to succeed.

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How to make the magnet stronger

• Increase current.
• Use a separate power supply for the magnet.
• This would involve constructing a DC to DC power
  converter.
• Change the material the core is made of
• This is currently cast iron
• Alternatives are silicon or ferrite.
• Change the shape of the core.

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Prototype Electromagnet Diagram
Magnetic Flux
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Strength of Magnet E core
Magnetic Flux
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How the current affects strength of the magnet
This equation is derived from the Biot-Savart law.
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Summary

• We are adapting a Stamp bug so that it can take
  part in the orienteering event at the Stamp bug
  Olympiad in the spring.
• The main modifications are the addition of
  wireless communications to the bug and an
  electromagnet.
• Work is still progressing on the electromagnet,
  it is currently to weak.
• Solutions which are being considered making the
  magnet stronger or a mechanical solution.

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Questions?

• j.harris-06_at_student.lboro.ac.uk