Introduction

This project has been designed, in order that you gain a better understanding of components, and how they can be connected together. By studying the effect of LEDs in series and parallel, and how a 555 chip can be used in an astable configuration. You will use breadboards to experiment with and decide on the final components you will use in your astable multivibrator circuit. You will explore the use of plastics, particularly acrylic for the casing of this project.

external image photo_01.jpg

Learning Outcomes

  • Practical application for LEDs in series / parallel
  • Astable configuration of a 555 IC
  • Soldering techniques
  • Casing design - sketches, orthographic views, isometric & perspective, Google Sketchup
  • Casing manufacturing - laser cutter, TechSoft 2D Design, line bender, oven, using jigs and formers,
external image safe_20.gif

555 Safety Light Project

Making a timer using a 555 IC circuit configured as a astable circuit.
  1. You are going to finish the preparations of the PCB, ready for soldering. Use the wire wool, and drill the holes.
  2. You are going to collect and prepare the components.
  3. Some components will be placed straight onto the PCB and others will first have flying leads attached.
  4. Insulation needs to be added to components such as LED's after they have been soldered.
  5. Flying leads need to be twisted to make them stronger and tidy (good practice).
  6. Once soldered the 555 chip is inserted into the holder.

You are going to design the casing for the safety light - which will be made entirely of Acrylic
For this part of the project you are going to learn about materials, manufacturing techniques and how to draw your casing ready for manufacture, and you are going to create a Google Docs presentation about what you have learnt and created.

Drawing Techniques

To start with you are going to choose an existing mold which will be the casing for your timer.
  1. You are going to draw accurate, and detailed orthographic views of the casing, including dimensions.
  2. You are going to draw accurate and detailed oblique drawing of your casing, and add some colour.
  3. You are going to use Google Sketchup to create orthographic and isometric views of your casing including dimensions.
  4. You are going to research laser cutting, injection moulding
  5. You are going to record (Schedule) how you made your casing - methods of manufacture,
  6. Health and Safety

Materials & Software

You will learn how to use the following software:
  1. Google Sketchup
  2. Techsoft 2D Design
  3. Focus on Plastics & Resistant Materials

Manufacturing

You will learn how to use the following equipment
  1. The line bender
  2. The laser cutter
  3. The oven

Links for Safety Light Casing

Orthographic Drawing
http://www.animatedworksheets.co.uk/webgate.html
http://www.technologystudent.com/designpro/ortho1.htm
http://www.technologystudent.com/despro_flsh/clock1.html
http://www.slideshare.net/robjwise/multiview-sketching
http://www.slideshare.net/docsclass/line-conventions-presentation
http://www.teachertube.com/view_video.php?viewkey=72a8401889ac64749e12

Dimension Practice
http://www.slideshare.net/robjwise/dimension-practices

Oblique Projection
http://www.slideshare.net/robjwise/oblique-pictorials-156130

Plastics
http://www.technologystudent.com/joints/joindex.htm

Laser cutting
http://www.technologystudent.com/laser1/laser8.html

TechSoft 2D Design
http://www.siastraining.co.uk/TVEAZcadcam%20site/oldtveaz%20cadcam%20resources.htm
Google Sketchup
https://msc-ks4technology.wikispaces.com/Google+SketchUp+Introduction

References

This project is taken straight from the following website. Thanks great work.
https://homepages.westminster.org.uk/electronics/Lower%20Shell/safety.htm

BackToMenuBtn.jpg