2011 School-assessed Task Report. Systems Engineering: Units 3 and 4 BACKGROUND INFORMATION. UNIT 3 Systems engineering and energy

Transcription

1 2011 School-assessed Task Report BACKGROUND INFORMATION Systems Engineering: Units 3 and 4 The School-assessed Task contributes 50 per cent to the study score and is commenced in Unit 3 and completed in Unit 4. Components of the task relate to Unit 3 Outcome 2 and Unit 4 Outcome 3. UNIT 3 Systems engineering and energy Outcome 2 Design, plan, construct and document an integrated system to be completed in Unit 4, Outcome 2, and effectively use diagnostic procedures for the system. Nature of task A record of design, planning and production and Production work UNIT 4 Integrated and controlled systems engineering Outcome 2 Select components for, construct, diagnose, adjust, modify and repair an integrated technological system and its control devices commenced in Unit 3, Outcome 2, and provide an evaluation report of the system, its performance and the management of the project. Nature of task Production work accompanied by a record of progress and modifications (pictorial and text material) and A report of diagnostic testing and performance data and An evaluation report. Scope of task The record of design, planning and production should include: a design brief (student or teacher generated) criteria for evaluating the integrated, controlled system research (background information to produce ideas for the design options such as safety, relevant Australian Standards, conventions, components, materials, processes, component assembly methods, suitability of tools, equipment and machines). Students must accurately cite all sources of information they use 1

2 design alternatives and options. Where relevant, alternative options should be provided and the preferred option should be clearly indicated with justification for its selection a design plan (drawings, sketches, annotations, diagrams, block diagrams, flow charts) for the configuration, assembly, integration and resourcing of manufactured systems, subsystems and components intended to produce an operational device with a control device components and materials list, including sources and cost a production work plan (including processes, proposed methods of diagnostic testing and a timeline for the manufacture of the integrated system) a record of progress that may include photographic evidence of production work (e.g. logbook) including decisions made and notes of modifications with justifications. Where appropriate, students should use information and communications technology (ICT) in the production of the record of design, planning and production and documenting diagnostic testing and the evaluation report. Where ICT is used, hard copy printouts must be provided. One product only is to be completed over Units 3 and 4. By the end of Unit 3 the production work should be partially constructed. By the end of Unit 4, the production work will result in an operational device in the form of an integrated system with a control device, i.e. a system which is a functional integration of a mechanical subsystem (includes pneumatic, hydraulic) and an electrotechnology (electrical/electronic) subsystem (includes microelectronic). All products must be compliant with safety standards and Australian Standards. Risk assessment and risk management must be addressed throughout the design, construction, testing and operation of the product, which must adhere to safety standards, laws and regulations. In Unit 4, the evaluation report should be based on the previously developed criteria. The report will include references to the results of at least one diagnostic test carried out on the student s system to assess the functioning and performance of the integrated system with a control device, providing it is not hazardous to do so. When undertaking diagnostic procedures students need to document (using appropriate technical language): the purpose of the test procedural steps to perform the test including the equipment used expected results actual results of the test in quantified (numerical) form explanation of the results. Students are also required to evaluate their management of the project and their work practices. Teachers must sight and monitor the development and documentation of the student s work on a regular basis. The Authentication Record for School-assessed Tasks should be used for monitoring student s work in progress for authentication purposes. This sheet must be made available if requested by the VCAA. 2

3 GENERAL COMMENTS Advice on management and organisation Conditions which are conducive to student achievement in the School-assessed Task include well-managed, organised classrooms and work areas and provision of relevant technical resource materials. Teachers need to provide guidelines on the selection of appropriate tasks, timelines, due dates and the requirements of the task. Regular monitoring of progress is also important in supporting and encouraging students through their tasks. Discussion and ongoing feedback assists students in remaining focused on their work throughout the duration of the task. Structuring the task through the various stages of its development is useful and timelines should be set to assist students. In addition to observing the development of the individual School-assessed Tasks, teachers should provide the students with the appropriate documentation required and keep appropriate records to verify student work is their own by using authentication documentation. Teachers can access the 2012 documentation and support information at: Specific information Features of successful folio and production work A wide range of productions were explored in the School-assessed Task. Most students negotiated production topics with their teacher. They organised work plans, work processes and set goals for completion and evaluation. The 2011 review identified some very successful folios and production work. An increasing trend has been for the students to produce photo journals. This is where research ideas have been explored and the planning, design, construction and final testing of the built system is photographically recorded. The other increasing trend is the application of ICT to provide Gantt charts, which enable comparison of the intended construction timeline with the actual timeline. Detailed journaling of the research undertaken and production processes went hand in hand with quality work in the production activities. Successful student work exhibited the following features. The production tasks were completed using a diverse range of work processes. These processes required a high degree of skill and knowledge. Design plans were thorough, in depth, detailed in content, with a range of design proposals or options. Justifications were made for selection of appropriate options and diagnostic tests of the solutions developed were planned with expected and actual outcomes identified. A sound analysis of the test data was made and explained. Evaluation reports were thorough and discussed the production activities as well as the practical outcomes of the task. Production activities involved working on an integrated system, its subsystems, parts and components. Appropriate steps were taken to control the system, its inputs, processes and outputs of completed systems were operational and produced to a very high standard of assembly and finish. Work required a significant effort and ample time to achieve completed and operational status. Folio work was of a high standard in content and detail and a range of appropriate communication techniques was used to present information and design work. The Teacher Additional Comment sheet Schools were asked to provide the Teacher Additional Comment sheet for all student work being reviewed. It appeared that the application of this documentation was widely misinterpreted. The February 2011 VCE, VET and VCAL VCAA Bulletin provided a copy of the Teacher Additional Comment sheet and information on how it should be used, as follows: Teachers should photocopy the Teacher Additional Comment sheet and make notes of observations of students during the production of the School-assessed Task. The Teacher Additional Comment sheet should not be filled in retrospectively, that is, following 3

4 notification of visitation. As the production work for the School-assessed Task occurs over a period of time, the Teacher Additional Comment sheet can also assist teachers in their record keeping. Teachers may find it useful to refer to the comments on the sheet when assessing the four criteria related to the production. The criteria related to the production work are Criteria 3, 4, 5 and 6. In addition, these criteria relate to the key skills listed in the production outcome in the study design. The reviewers reported that in many incidences the Teacher Additional Comment sheet was not provided at all. When it was provided, the Teacher Additional Comment sheet consistently appeared to have been filled in retrospectively, purely as result of the notification of the review. Although the application of this document has improved over recent years, quite commonly, teachers didn t restrict their comments to the related production work of Criteria 3, 4, 5 and 6. In a couple of more extreme cases the document appeared to be used to request special consideration from the reviewers. Nevertheless, the reviewers commented that the documentation in which the specific Criteria 3, 4, 5 and 6 were observed and discussed were directly useful in determining the reviewed assessments. It should be noted by teachers that the intent and purpose of the Teacher Additional Comment sheet remains unchanged in The document should be used to assist teachers with the assessments of the School-assessed Task, and can be requested by the VCAA as evidence in the school-based audit and review process. Types of products Examples of successful production activities selected for the School-assessed Task were: micro-controlled toys, games, monitoring and control systems (such as remote weather stations) electromechanical toys and games controlled robot arms and vehicles compliant electric bicycles and scooters controlled model systems (such as automated model houses) model cars, watercraft and aircraft controlled sporting equipment and accessories (such as mechanical ball throwers) audio equipment with integrating mechanical components (such as ipod-connected amplifiers with some integration of mechanical components). Areas of strength and weakness Production tasks that were of a high standard reflected the emphasis on quality practical work. The 2011 review identified more systems products than in previous years to be non-integrated, commonly only being electronic. Some products that were purely mechanical were generally a result of incomplete work, with the intention to integrate the system shown in the planning only. The products produced that fully met the intention of School-assessed Task were characterised by being controlled, integrated systems which included a clear statement of input process output and control of integrated electrical, electronic and mechanical subsystems. An increasing number of micro-controlled systems (predominately Picaxe based) were undertaken in Non completion of work In 2011 the reviewers reported an increase in non-completed School-assessed Tasks. A number of students in past years have not completed the planned and designed product to the intended level or finish. There was a significant increase in the number of students who did not complete diagnostic testing and evaluating their processes, work practices and product. Specifically, diagnostic testing and final evaluation were completely omitted. On occasions some reference to early testing of components was made in the work journal. No particular 4

5 reason for the decrease in work completion was apparent, other than poor student planning and running out of time to complete the work assessed by the final three criteria. Production work safety Overview The processes that the students are involved in will by their very nature have an element of inherent but minor risk. This risk needs to be monitored, documented and minimised through all stages from conception, during all production activities and in the final use of the product, as specified in the skills in Criterion 2: Ability to assess and document safety risks associated with the production task. Some of the completed projects observed in the review appeared to be far from safe to use. The accompanying documentation did not reflect the overall intent of managing risk as a key and overall concept in students undertaking the School-assessed Task. Quite commonly the focus of the risk assessment was far too narrow. The risk assessment needs to consider the safety risks associated with the production task in its entirety. The planning and production stages, appropriateness and safety of the materials and equipment used, and the associated risks of using the final completed project, all need to be covered. Materials safety The reviewers identified some completed systems that potentially could be unsafe. Pressure vessels were of particular concern. Certification of compliance with appropriate standards should be provided, which could add significantly to the total cost of the production task. The use of glues and materials that produce potentially toxic fumes such as fibreglass resins required the students to document or show through photographic evidence that it had been undertaken in an appropriate environment with good ventilation. While not encouraged, composite materials such as MDF can be provided by a supplier cut exactly to the required size, thereby reducing the associated risk. Electrical safety In the 2011 review, compliance with electrical safety requirements was generally better; however, it was still evident that some dangerous productions had been undertaken, in both the inappropriate selection of components and the equipment used, and/or the practices that had been undertaken by students. For example, students should be directed by the teacher to use controlled low-voltage circuits (typically 12V DC), rather than producing circuitry to control mains (240V AC). Even if control systems were tested and tagged, it was observed that speed controlled 240V motors were not appropriate for small spit roast barbeques. The engineered aspects of low voltage motors are clearly better in terms of the appropriateness of the size, performance and overall safety. As the State regulator, Energy Safe Victoria < is quite specific in the ruling that students should not work on mains 240-volt products and equipment. This extends to the wiring of mains connections of equipment. All mains wiring must be undertaken by a suitably qualified, licensed person. This does not preclude students from using mainspowered equipment as part of their overall project. The equipment is subject to routine testing and tagging as required for all the portable electrical equipment used in schools. Similarly, this applies to mains-powered portable electrical equipment used in student projects. Typically, students used mains-connected plug packs and low-voltage power supplies to power the electrical section of their built systems. In the review in one instance an Australian/US step-down transformer had been used. While the working voltage was reduced to 110V AC, the bare mains (110V) connections inside the system were clearly not compliant and posed unacceptable risk to anyone working on the circuit. Examples of appropriate electrical equipment that has been certified as compliant and used as part of the constructed systems included laptops, power supplies, audio amplifiers, exhaust fans, electric drills and video monitors. 5

6 Motorised vehicles The 2011 review showed that the general compliance for motorised vehicles has vastly improved. Motorised vehicles produced were commonly motorised bicycles or scooters. It had been observed in previous years that motorised vehicles were not compliant due to poor structural frames and overpowered petrol engines. The use of battery-powered electric motors, which are rated below 200 watts and utilise the structural integrity of existing bike or scooter frames with the original brakes, has resulted in a far safer and more compliant product. Assessment criteria Criterion 1 Skill in developing a design plan for an integrated system. Use of a design brief to outline a project that is an integrated system with a control device. Use of a range of presentation methods for communicating ideas and design plans for the proposed system. Use of research in developing options. Development of a range of options and justification for the preferred option. Development of a range of criteria that are suitable for evaluating the product. It was widely reported by the reviewers that Criterion 1 was generally done well across all the schools that were reviewed. In the majority of cases, students had completed this criterion with some level of success. The range and ways to present information varied greatly. No one format or presentation method was considered superior. Reviewers often commented about the different good ideas students had in developing design plans for their integrated systems projects. It was desirable that the student showed the journey they had travelled. It was useful when very early primary sketches were included. To achieve a very high, students were required to complete a thorough design brief that provided a clear insight into the proposed project accompanied by a very clear statement of what was intended to be built. Within these high range responses, the research was very specific to one type of project that was to be constructed. This also extended to at least three specific options being presented (of the one type of project). Often some form of ranking was developed to show the justification for the preferred option. The ranking or scoring was presented in many forms, including written engineering judgments, cost benefit analysis and diagrammatic explanation. Sometimes it just came down to what was readily available. It was observed that a summarised tabulated presentation of the preferred options scored highly in most cases. Similarly the developed range of criteria for evaluating the product needed to be highly relevant to the proposed product. Often the developed criteria were ranked into a number of areas with a weighting or expressed as essential, desired and preferred. Reviewers noted that poor student performance in this criterion was often indicated by a confused design brief, unclear overall intent, and subsequent poor planning. Reviewers read the design brief multiple times and were still unsure of what the student was ultimately planning to build. Criterion 2 Skill in preparing the production plan. Sequence of steps needed to complete the product in the available time. Knowledge of relevant Australian Standards and the components, tools, equipment, machines, materials and processes required to make the integrated system. 6

7 Ability to prepare a materials and components list (including their sources and costs) required to produce the system. Ability to assess and document safety risks associated with the production task. The reviewers reported that work assessed through Criterion 2 was also generally well done. The majority of students completed work for this criterion with some level of success. To achieve a very high in this criterion some specific features were included. Students usually opted to use a Gantt chart to show a sequence of necessary steps to complete the product in the available time. Gantt charts that indicated the intended timeline were revisited at a later stage to compare the intended timeline with the actual production timeline. Specific knowledge of Australian Standards was covered by students in very board terms. Often students sourced some general information which related to the general area in which they were working, such as general standards related to the manufacture of toys. This was seen as quite adequate in meeting the assessment criterion. High level responses in demonstrating knowledge of components, tools, equipment machines and processes were broken into distinct sub-fields. Commonly, high scoring students grouped together the tools, equipment and machines and presented them in tabulated format. The tools, equipment and machines were named and accompanied by images. The tabulated format allowed students to indicate the associated risks, precautions and Personal Protective Equipment (PPE) associated with using the tool, machine or equipment. The presentation of the materials and processes to be undertaken were (sometimes logically) included in the common group of tools, equipment and machines, however, depending on the nature of the production it was often appropriate to present materials and processes separately. The high achieving students produced very comprehensive component lists, once again in a tabulated form, detailing suppliers and cost. Students commonly used the Jaycar Electronics website for components and costing. In 2011, it was common to see components sourced via ebay. High achieving students presented a very broad and comprehensive view of the safety risks associated with the production. They considered the inherent risks and safety issues in design, construction, testing, and in a range of aspects of the final use of the product. Criterion 3 Skill in the application of processes in producing an integrated system. Range of processes used. Degree of difficulty in the processes used. Ability to record progress and modifications. Efficient use of time during production. The range and types of production work was extensive. Common integrated system types were listed previously in this report. To achieve a very high in Criterion 3 students needed to select a project that was clearly an integrated system and to demonstrate a significant range of processes at a reasonable degree of difficulty. Typically these processes involved the design of circuits and mechanical parts, making printed circuit boards, wiring and looming, fabrication of parts, shaping and bending, joining and welding, drilling and shaping, filing and finishing of surfaces, and painting (incorporating graphical designs). Progress and modifications were generally recorded in the form of a journal, often with supporting photographic evidence. As mentioned previously, the Gantt chart was often used 7

8 to compare the expected timeline with the actual timeline to determine efficient use of time during the production. Students who performed poorly in this criterion often elected to produce a system which was not integrated and which was more commonly only electrical or electronic in nature. It followed that the range and difficulty of processes that could be demonstrated were greatly limited. Criterion 4 Skill in the use of tools, equipment and machines. Range of tools, equipment and machines used. Competence/technical skill in the use of tools, equipment and machines. Appearance and finish of the product. To achieve a very high the students needed to demonstrate a very high level of competence in using a range of tools, equipment, and machines. The reviewers commented that quality work was easily identified. In some cases students had opted to send work out for finishing because they required a high level of finish and did not have the resources to complete this themselves. In this situation students provided supporting documentation in their journal and provided quotes on work to be done and the associated costs. A common example of outsourcing was the application of powder-coat finishes on steel frames. Particularly with complex systems being built, the reviewers considered the fine balance between the ability of students to safely and effectively complete a particular process and on the other hand have some outside assistance to achieve the desired level of finish of the final product. Teachers are encouraged to discuss these issues with the students. It would not be appropriate to expose students to a high level of risk to satisfy a requirement that they demonstrated technical skill competence in in a particular process. An example of this would be if a student had larger sheets of steel that were guillotined and supplied cut to size as specified in their planning. Criterion 5 Skill in realising the plan. Performance and quality of the completed technological system with comparison to the plan and recorded modifications. Suitability of the selection and use of appropriate materials, components, methods of assembly and conventions to meet the design plan. For students to achieve a very high in Criterion 5 they had to show they had achieved what they had set out to do in their planning. The stated performance and intended quality of the product had been met. The changes to the plans and modifications undertaken were documented and recorded in the student s journal. The completed product needed to reflect that the selections that had been undertaken were effective and appropriate for their integrated system Criterion 6 Understanding of appropriate diagnostic test procedures. Planning of the tests. Skill in carrying out the tests on the system developed by the student. Accessing and using relevant technical information. 8

9 It was reported by the reviewers that Criterion 6 was poorly done by a significant number of students. It was observed that an increasing number of students did not undertake or complete the written component for this criterion. The predominant area of improvement was the required testing on the system that they had constructed. In previous reviews, it was evident that diagnostic testing was undertaken on totally unrelated products. To achieve a very high, students showed a very good understanding of appropriate tests that could be undertaken on the system or sub-systems directly associated with the system. Generally these tests were dynamic tests when the system was operating normally, rather than static tests. High achieving students planned their tests on their own system. Often these planned tests required research of relevant technical data. Additional jigs or test conditions were developed to reduce error. The high achieving students demonstrated understanding and skill through applying very appropriate and relevant tests to the particular system parameters, whether that be noise measurement, power usage, light intensity, or measurements with appropriate test equipment, such as digital multimeters, for the task. Quality testing was documented with diagrams of set-ups or a series of photographs showing the set-up for carrying out the tests. Criterion 7 Analysis of data gained from diagnostic testing Specification of test data in quantified (numerical) form. Explanation of the actual results versus the expected results. Accurate use of technical information and appropriate technical language to explain results. A significant number of students performed poorly in Criterion 7. To achieve a very high, students had to provide logical analysis of the test data gained. High performing students commonly elected to present the quantified numeric data in a tabulated form. This enabled a range of actual results to be easily compared to expected results. Correct and appropriate technical language was easily identified by the reviews. Those students who completed this criterion but performed poorly typically did not present relevant data. Their poor understanding of technical language was regularly apparent to the reviewers when measurements of voltage, current, resistance and power were involved, as these terms and associated units of measurement were often muddled or exchanged incorrectly. Criterion 8 Evaluation of the processes, work practices and the product Effectiveness of the production work plan. Difficulties encountered and how these were addressed. Suitability of the product with reference to the previously established criteria. Description of how the system could be improved. A significant number of students did not complete an evaluation report. The evaluation report provided a summing up of the overall project, giving reviewers an insight into the whole project and the journey the student had taken. It was commendable when students provided a frank and honest assessment of the whole process. To achieve a very high the students provided a comprehensive and honest report. While no particular word limit was specified, reports of at least a full page were generally comprehensive enough to reasonably cover the relevant dot points. High achieving students were not limited in their discussions. 9

10 Students who limited their discussions, sometimes to a just a few lines, performed poorly. In circumstances where a separate evaluation report was not provided, reference was made to the journal for evidence of an evaluation of processes, work practices and the product that had been undertaken. In most cases, low scores were achieved if an evaluation report was not provided. 10