Knowledge of machines CMT 6-6
Achievement Standard 1.25 AS 91062
Machines consist of fixed and moving parts that modify mechanical energy and transmit it in a more useful form. A simple machine; such as a lever, a pulley, or an inclined plane; alters the magnitude or direction, or both, of an applied force. Complex machines have internal energy systems; such as electric motors, steam engines, turbines, combustion engines, solar energy systems, nuclear systems; that combine with levers, inclined planes and/or screws to enable the machine to perform their intended function/s.
Learning objective: CMT 6-6
Students will:
- demonstrate understanding of basic concepts related to machines.
Indicators
Students can:
- explain the purpose of levers, inclined planes and screws
- explain the purpose of a range of mechanical components
- explain the advantages and disadvantages of pneumatic and hydraulic
systems
- explain how a machine provides the mechanical advantage and motion
- discuss why particular levers, inclined planes and screws, and mechanical
components were selected to ensure the mechanical advantage and motion in machines.
Progression
Prior to level 6 students should be developing an understanding of range of simple machines such as cogs and cranks and the techniques used when constructing simple machines. Relevant health and safety and codes of practice should also be a focus of the teaching and learning programme.
At level 6 students learn about simple machines such as levers, inclined planes and screws and how when combined with mechanical components they are able to achieve a mechanical advantage and motion.
The Teacher Guidance section provides information that supports teachers scaffolding of learning from levels 1-8 of the curriculum. This allows for differentiation of a programme of learning.
The deliberate use of provide, guide, and support in this section signals that as students' capacity for self-management increases, teachers progressively reduce the level of scaffolding provided.
- Provide – the teacher should take full responsibility for introducing and explicitly teaching new knowledge, skills or practices.
- Guide – the students have a level of understanding and competency on which they can draw but the teacher remains primarily responsible for continuing to develop these.
- Support – the students take primary responsibility for their own learning, drawing on all their previous experiences to consolidate and extend their understanding. The teacher is supportive rather than directive.
- The Teacher Guidance also uses the term ensure to indicate when the teacher plays a monitoring role to check that conditions critical for learning are present.
Teacher guidance
To support students to understanding basic concepts related to machines at level 6, teachers could:
- provide opportunity for students to explain the purpose of levers, inclined
planes and screws
- provide opportunity for students to explain the purpose of a range of
mechanical components within a range of machines
- guide students to explain the advantages and disadvantages of pneumatic
and hydraulic systems
- guide students to understand how a range of machines provides mechanical
advantage and motion
- guide students to discuss why particular levers, inclined planes and
screws, and mechanical components were selected to ensure mechanical advantage and motion in across a range of machines.
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Contexts for teaching and learning
This learning objective is a knowledge objective and hence there is no requirement for students to actually construct the machine(s) they are studying. However within a programme of work it would possible to tie the knowledge related to this learning objective with a project where students are actually designing and/or constructing an outcome that involves a machine or is a complete machine. Knowledge of machines could be covered before students design and make their own technological outcome that includes parts of or a complete machine. For example students could construct a simple wind generator or a radio control car.
For this objective a machine will include one or more levers, inclined planes and/or screws, and one or more mechanical components. Examples of machines may include but are not limited to: mini motorbikes, truck mounted cranes, block and tackle, chain block, pneumatic or hydraulic jack, and turntable. Examples of mechanical components include:
- bearings may include but are not limited to – plain, ball, roller, needle, thrust
- cams and followers; may include but are not limited to – cams such as plate and eccentric; followers such as needle, roller, flat, and offset
- pivots and linkages; may include but are not limited to – pivots such as fixed and moving; linkages such as: parallel, reverse and sliding crank motion
- gears may include but are not limited to – spur, bevel, helical, rack and pinion, worm, and idler
- belt or chains and sprockets may include but are not limited to –flat belt, v-belt, duplex chain or double belt, and tooth belt
- shafts and bearings may include but are not limited to – solid shafts, hollow shafts, ball bearing, roller bearing, and conical bearing.
Students will need to learn about and investigate a range of machines and collect evidence that:
- explains the purpose of levers, inclined planes and screws
- explains the purpose of mechanical components
- explains the advantages and disadvantages of pneumatic and hydraulic systems
- describes the mechanical advantage and motion provided by a machine
- explains how a machine provides the mechanical advantage and motion
- discusses why particular levers, inclined planes and screws, and mechanical components were selected to ensure the mechanical advantage and motion of a machine.
This evidence could include annotated sketches, mock-ups, models, photographs, quotes, and video clips.
- The teaching and learning programme could incorporate a variety of activities such as:
- A site visit(s)
- Futrureintech ambassador or other guest speakers
- Case studies, technical manuals and books relating to how machines work and internet research
- Deconstructing and experimenting with existing machine and components
- Using simulation and virtual machines to explore functionality
Literacy considerations
To be successful students will need to understand the assessment language of describe, explain and discuss. Note the following definitions:
- to identify is to state an idea
- to describe is a statement that gives details about the outcome or idea
- to explain is to describe in detail with reasons – often including the how and why
- to discuss requires an explanation that is comprehensive, detailed, broad and show evidence of some complexity in thinking. It may be a reasoned argument presenting a particular point of view, a comparison and contrast between tow ideas or concepts or it may be a detailed reasoning and relationship between several complex ideas.
Students will need to be supported in their understanding of how describe, explain and discuss look when collecting their evidence for assessment and writing frames and structures or template can be used judiciously to support this. Care must be taken not to over template writing frames, which may not allow students to achieve against the criteria.
Students will need to understand the following key terms and categorisation:
Mechanical components include:
- bearings may include but are not limited to – plain, ball, roller, needle, thrust
- cams and followers may include but are not limited to – cams such as plate and eccentric; followers such as needle, roller, flat, offset
- pivots and linkages may include but are not limited to – pivots such as fixed and moving; linkages such as parallel, reverse and sliding crank motion
- gears may include but are not limited to – spur, bevel, helical, rack and pinion, worm, idler
- belt or chain and sprocket may include but are not limited to – flat belt, v-belt, duplex chain or double belt, tooth belt
- shafts and bearings may include but are not limited to – solid shafts, hollow shafts, ball bearing, roller bearing, conical bearing.
A machine will include one or more levers, inclined planes and/or screws, and one or more mechanical components.
Students will need to be able to:
- explore, research and gather information related to basic concepts relating to machines
- For example in the context of a mini motorbike this would mean collecting information about the following concepts in order to demonstrate their understanding (from the Assessment resource http://ncea.tki.org.nz/content/download/4198/13670/file/tech1_25_CMT_v3_feb15.doc)
- levers, inclined planes, screws, and mechanical components and why they were chosen to achieve mechanical advantage (for example, to provide more power or speed, or to make them easier to stop)
- hydraulic and pneumatic systems and the advantages and disadvantages of each of these systems (for example, what maintenance they require, what faults are likely to occur more commonly in each type of system, which system gives the greater speed)
- the path of motion through the levers, inclined planes, screws, and mechanical components.
- use technical language, diagrams, and symbols to explain how machines work
- evaluate and present evidence to demonstrate their understanding. This may be written, digital, diagrammatic and annotated or combinations of these.
Resources to support teaching and learning
Indicators of progression:
Other resources
- Culley, R. (ed). (1977). Fitting and Machining. TAFE Publications Unit.
- Pedersen, G. (2011). Kontiki Fishing. The Shed, December 2011–January 2012.
Operator manuals for milling machines:
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Assessment for qualifications
The following achievement standard(s) could assess learning outcomes from this learning objective:
- AS91062 Construction & Mechanical Technologies 1.25: Demonstrate understanding of basic concepts related to machines
Key messages from the standard
The teacher may select or negotiate with students a suitable machine for them to investigate. The machine could be one that a student(s) has designed and/or manufactured, or one selected by teacher and or students. It is key that students focus on one or more machines to find out their purpose, how they work, and why they are used.. In a rural context this may be a posthole borer, a tractor, a seed-drilling machine, or a hydraulic tipping trailer, for example.
Evidence should be collected into a report or presentation as negotiated with the student and could include annotated photographs or drawings, diagrams drawn, images of models the student has made, notes from group discussions, and written explanations. Evidence can be collated as a report or a presentation accompanied by a model, display board, or slides,
For this achievement standard a machine will include one or more levers, inclined planes and/or screws, and one or more mechanical components.( Explanatory Note 4)
For this standard students should to explore and investigate the selected machine(s) or components and demonstrate their understanding of:
- the components and their functions within machines
- levers, inclined planes, screws, and mechanical components and why they were chosen to achieve mechanical advantage (for example, to provide more power or speed, or to make them easier to stop)
- hydraulic and pneumatic systems and the advantages and disadvantages of each of these systems (for example, what maintenance they require, what faults are likely to occur more commonly in each type of system, which system gives the greater speed
- the mechanical advantage and motion provided machine.
Mechanical components include:
- bearings may include but are not limited to – plain, ball, roller, needle, thrust
- cams and followers; may include but are not limited to – cams such as plate and eccentric; followers such as needle, roller, flat, and offset
- pivots and linkages; may include but are not limited to – pivots such as fixed and moving; linkages such as: parallel, reverse and sliding crank motion
- gears may include but are not limited to – spur, bevel, helical, rack and pinion, worm, and idler
- belt or chains and sprockets may include but are not limited to –flat belt, v-belt, duplex chain or double belt, and tooth belt
- shafts and bearings may include but are not limited to – solid shafts, hollow shafts, ball bearing, roller bearing, and conical bearing.
For the most up to date information, teachers should be referring to the latest version of the standards, conditions of assessment and assessment resources on TKI and the moderators reports, clarifications documents and student exemplars on the NZQA website. See links below.
Resources to support student achievement
Assessment resource:
Annotated Exemplars
Last updated February 21, 2023
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