THE ELECTRONIC DICE Teacher s manual a technology project for secondary education
Many parties were involved in making this lesson / project available for schools: This technology project was originally developed by Philips (The Netherlands) for the Dutch Jet-Net-project and incorporated in the EU Ingenious project of European Schoolnet (EUN). Jet-Net, the Netherlands Youth and Technology Network, is a partnership between companies, education and government. The aim is to provide higher general secondary school (HAVO) and pre-university school (VWO) pupils with a true picture of science and technology and to interest them in a scientific-technological higher education course. European Round Table of Industrialists ERT is a forum bringing together around 45 chief executives and chairmen of multinational industrial and technological companies with European heritage with sales volume exceeding 1,000 billion and thereby sustaining around 6.6 million jobs in Europe. ERT advocates policies at both national and European levels which help create conditions necessary to improve European growth and jobs. ERT was the initiating force for the EU Coordinating Body (ECB), now called Ingenious, to disseminate proven best practices of industry-school cooperation to stimulate interest in careers in science and technology throughout the European Member States.. European Schoolnet (EUN) is a network of 30 Ministries of Education in Europe and beyond. EUN was created to bring innovation in teaching and learning to its key stakeholders: Ministries of Education, schools, teachers and researchers. The Ingenious project is coordinated by European Schoolnet. This document is supported by the European Union s Framework Programme for Research and Development (FP7) project ECB: European Coordinating Body in Maths, Science and Technology (Grant agreement Nº 266622). The content of this document is the sole responsibility of the Consortium Members and it does not represent the opinion of the European Union and the European Union is not responsible or liable for any use that might be made of information contained herein. This is a publication of: Philips Human Resources Benelux / Jet-Net, PO Box 80003, 5600 JZ Eindhoven Edition: English version 2.2, March 2012 for European Schoolnet Ingenious programme 2-1-2012 Koninklijke Philips Electronics N.V. 2012 No part of this publication may be reproduced, stored in a database or retrieval system, or published, in any form or in any way, electronically or mechanically, by photocopying, photography or any other means without prior written permission from the publisher or European Schoolnet..
TEACHER'S MANUAL FOR THE ELECTRONIC DICE This technology project is intended for secondary school pupils in the age of 11-13 year. Optional modules in the booklet make it possible to vary the lesson in depth and match wit the level and experience of the target group. PROJECT STRUCTURE The course material consists of one general section and five optional modules, all combined in a single book. The different sections are clearly identifiable by the footer. The general section consists of four parts: 1. the history of dice; 2. the components of the electronic dice; 3. building the electronic dice (practical); 4. testing the electronic dice. Parts 1, 2 and 4 of the general section will take up a total of approximately one lesson. The time required for part 3 (the practical) depends on your decision regarding the content of this assignment. You might for instance also decide to get the students to design and build a housing. See below in this manual for more on this. There are four optional modules: A. Explanation of the components B. Reading the colour coding on resistors C. How the electronic dice works D. Soldering The decision to have optional modules was taken because technology education in schools can vary considerably. By making a choice between various modules yourself, you can ensure that the project matches your own lessons as much as possible. In Optional module A we deal with the various components that make up the electronic dice. This is a general explanation and no questions are asked about it. It will take students about 10 minutes to read and understand the text of this module. Optional module B is about reading the colour coding on resistors. The module explains a rapid method of numerical coding on small components (compare for instance the barcode, which can only be read electronically). You will find three questions at the end of this module. Students will need about half a lesson to get through this module. 1
Optional module C. It is important that you deal with this module in your lessons. Otherwise students will not know why and how the electronic dice works. In Optional module C the operation of the electronic dice is explained using written text. In between the written passages questions are asked so that students can familiarize themselves with the text. An excursion is made into binary numbers. Students will need about one lesson to get through this module. Optional module D deals with the technology of soldering. CARRYING OUT THE PROJECT The various parts may for instance be carried out in the following order (the optional modules are in brackets): - The history of dice; - The components of your dice; (- Explanation of the components of your dice (Optional module 1);) (- Reading the colour coding on resistors (Optional module 2);) - How the electronic dice works (Optional module 3a or Optional module 3b); - Making your dice (possibly in combination with Optional module 4); - Testing your dice. To assist the organisation in the classroom it may be useful to vary the order of the parts for different students. In this way you can for example avoid a situation where all the students are doing the practical section at the same time. SOLDERING It is advisable to introduce the students in an earlier lesson to the technology of soldering before they start making the dice. The following points are important for successful soldering: - Provide extraction of solder fumes; - Use 25-watt soldering irons with a sharp tip; - Use resin core soldering tin wire with a diameter of 0.7 mm; - Use a third hand to secure a PCB or electronic components; - Use a desoldering pump to suck up excess tin and re-open holes; - Emphasise to students that when soldering the chip legs they must not use too much solder so as to prevent the legs from being soldered together; - Use small side-cutting nippers to cut off legs that are too long. 2
Some components are sensitive to the direction of the current and could be damaged if the student places them incorrectly. We therefore advise handing out the batteries only after the workpiece has been checked. Some instructive video YouTube links: http://www.youtube.com/watch?v=ll8gcqqxb2e&feature=related http://www.youtube.com/watch?v=gf283e_j6ii&feature=related http://www.youtube.com/watch?v=qglcyhf1-ig THE WORKPIECE You may decide to get the students to build the electronics into a workpiece, as shown in the photos on the front page. The PCB has a fracture line between the area containing the LEDs and the other components. The students can use this in the workpiece. Make sure in that case that the students first break the PCB and only then start soldering. So-called spacer sleeves can be used for mounting (parts of) the PCB in a wooden workpiece. The PCB can be screwed onto wood using cross-head screws (size 2.5 x 13) via PCB holes and spacer sleeves. Contact adhesive can be used for fastening to plastic. BLOCK DIAGRAM OF THE ELECTRONIC DICE pulse generator pulse counter 1-6 LEDs o o o o o o o finger switch Functionally, the electronics in the dice consists of three components. A circuit (pulse generator) generates voltage pulses at a rapid rate; these pulses are then counted by an electronic counter. This counter counts from 1 to 6, then goes back to 1, and so on (the value of the dice). The state of the counter (1-6) is sent in binary form to the 7 LEDs: the display unit. When the counter is stopped with the finger touch button, the state is clearly and permanently displayed on the LEDs. When the dice is running free, the LEDs switch on and off very rapidly due to the speed of the pulse generator and it is impossible to see what state is being indicated. 3
ASSESSING THE PROJECT This project consists of a written section and a practical section. The marking criteria for assessing the written section are given in this teacher's manual. You can give a mark yourself on the basis of the number of points scored. No instructions are given for assessing the practical section (making the switch and the electronic dice). Since the content of the practical section will vary greatly from teacher to teacher, it is best if you assess the students' work yourself. To obtain a student s final result for this project you can for example take the average of the marks for the written section and the practical section. MARKING CRITERIA: General section 1 maximum score 1 in Iraq 2 maximum score 1 2750 + the current year 3 maximum score 2 4 x 4 x 4 x 4 1 there are 256 possible outcomes 1 4 maximum score 2 for a sketch of a correct switch 5 maximum score 1 approximately 100 times (or more) 6 maximum score 2 for a correctly filled-in table for the electronic dice 1 for a correctly filled-in table for the ordinary dice 1 7 maximum score 2 a correct conclusion based on the table 1 a correct explanation for this conclusion 1 8 maximum score 3 examples of advantages: - an electronic dice cannot roll very far; - an electronic dice takes up less space; - with an electronic dice you can also play in the dark; - the outcome cannot be influenced by the way the dice is rolled; - an electronic dice makes no sound. give 1 point for every correct advantage 4
MARKING CRITERIA: Optional module B: Reading de colour coding on resistors 9 maximum score 2 resistor A: 20 000 Ω (or 20 kω) 1 resistor B: 420 Ω 1 10 maximum score 6 the tolerance of resistor A is 5% 1 the value of resistor A may deviate by 0.05 x 20 000 = 1000 Ω 1 the value of resistor A is between 19 000 Ω and 21 000 Ω 1 the tolerance of resistor B is 10% 1 the value of resistor B may deviate by 0.10 x 420 = 42 Ω 1 the value of resistor B is between 378 Ω and 462 Ω 1 Note If the value of the resistors in assignment 1 has been incorrectly calculated, these values must continue to be used for the calculation in assignment 2. 11 maximum score 4 100 kω resistor: brown, black, yellow, gold 2 560 kω resistor: green, blue, brown, gold 2 Note Deduct 1 point for every incorrect colour band on a resistor, up to a maximum of 2 points. 5
MARKING CRITERIA: Optional module C: How de electronic dice works 12 maximum score 2 1 the lamp lights up for 1111 seconds 1 the lamp lights up for 9 x 10-4 seconds (or 0.0009 seconds) 1 13 maximum score 2 1111 the pulse counter counts to 6 times 6 1 this is 185 times 1 14 maximum score 4 01010 equals 10 1 10001 equals 17 1 01111 equals 15 1 11111 equals 31 1 15 maximum score 5 1 equals 001 1 2 equals 010 1 3 equals 011 1 4 equals 100 1 5 equals 101 1 16 maximum score 2 H5 H4 H7 H3 H2 H6 H1 Note For every incorrectly coloured-in lamp deduct 1 point, with a maximum of 2 points. 6