MATERIALS Design Sheets Five A3 design sheets were used to record the pupils work. They were pre-printed, with titles, assessment targets and instructions. They were titled: Research, Ideas, Final Idea, Planning and Evaluation. Manufacturing The Outer Case Pupils had some choice of sheet materials but were limited in size to two pieces measuring 170mm by 125mm. Opaque acrylic, 3mm, in a wide range of colours Clear acrylic, 3mm, in a limited range of colours including fluorescent. Birch plywood, 4mm MDF, 3mm A class discussion, that followed up a homework, involved assisting pupils to choose a suitable case material. Reasons for choice were recorded on the pupils ‘Ideas’ design sheets. Selection criteria included: Quality of Finish, Ease of manufacture, Cost, Durability, Safety Approximately half of the pre-cut pieces were pre-drilled and countersunk for easy set up on the Roland CAMM2. Product Analysis Product disassembly and analysis can be a challenge for pupils studying Systems and Control but gives them opportunities to reach the higher NC levels such as level 7. In this project a single ‘Steady Hand Game’ bought from Woolworths plc for £7.99 was disassembled and evaluated. The product used has clear weaknesses and allows pupils to consider improvements. Microcontroller Cost considerations and ease of use make the PICAXE the obvious choice of microcontroller. The PICAXE 08M chip is an 8 pin controller that operates reliable at 4.5v, in this project it provided one input and four outputs. This particular PIC is a recent addition and is very powerful for its size, containing an A/D converter and several pre-programmed tunes. Pupils could program their own tunes or download tunes from the web from free ringtone sites. The ringtones are ‘rtttl’ files that are imported into picaxe’s tunes wizard. There are advantages in allowing pupils to manufacture their own PCBs but it was decided that the emphasis would be on control so a pre-made PCB was used. This allowed pupils to populate and solder their own circuit quickly in order that they could then program their own board. Batteries External components add cost and complexity to a project so it was decided to use a small case that would house three AAA cells. The case also contains a slide switch. ICT Elements There are three main elements of ICT in this project.
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