A Years 9–10 design project: a two-motor drive base for a line or obstacle course, with a battery chosen against the brief, steering planned, built in a simulator then for real, and tested on a timed course.
Load these into Waypoints Prepare: choose Load URL and paste the copied address, or download the file and import it. In Prepare, the worksheet's Teacher edition shows the answers; the student copy hides them.
SlidesDownload Present from the browser, or export to PowerPoint or PDF.
WorksheetDownload Print the student copy; the Teacher edition has the answers.
Students will be able to
I can choose a battery and motors against a brief.
I can plan a robot's steering from its sensors.
I can test a robot on a course and evaluate it with data.
Timing
About 5 to 8 lessons (around 300 minutes). Inquire 1 · Develop 1–2 · Create 2–4 · Test and evaluate 1
Before class
Needs Power and motors (drivers, shared ground, batteries); LiPos only after the LiPo safety sign-off and if your risk assessment allows. Pairs with Mechanisms (gearing), CAD (a printed chassis) and the robotics simulator. The micro:bit Cutebot (Code › Robotics challenges) is a ready-made alternative base for classes without kits.
If you assess with MYP Design, the steps line up with the criteria:
A Inquiring and analysing: the brief, its criteria and constraints, and research into parts (Inquire).
B Developing ideas: a design specification, the circuit and code plan, and the test table written before building (Develop).
C Creating the solution: building it (in the simulator, then for real), following the plan and justifying changes (Create).
D Evaluating: testing against the specification, recording failures, improvements and impact (Test, Evaluate).
Otherwise, use the same four headings as a simple rubric: each step's reflect checks are the evidence list.
Running the lesson
Develop: the battery choice must be justified against all three numbers.
Create: drive straight first, then add one sensor.
Test: three timed runs, results in a table.
The hard part (on purpose)
Mechanical problems (loose wheels, a dragging chassis) look like code problems. Test the base driving straight before adding sensors.
When students get stuck
What you will see
A question to ask
The fix
The robot turns the wrong way.
Which motor slows when the sensor sees the line?
Swap the turn logic, or swap a motor's wires.
It resets when it starts.
Where do the motors get their power?
Their own battery, grounds joined.
Answers to the checks
Inquire: the brief: Sort each line of the brief: a criterion (what it must do, which you can test) or a constraint (a limit you must work within)? Completes the course in under 60 s → Criterion; Leaves the line at most once → Criterion; Runs for 30 minutes on one battery → Criterion; Two DC gear motors and a motor driver → Constraint; Battery 6–9 V, at most 150 g → Constraint; Chassis fits in 20 × 20 cm → Constraint Criteria are what you will test at the end; constraints decide what you are allowed to build with.
The battery: The two motors and the board draw about 900 mA together. Choose a battery that meets the brief (30 minutes using 80%, 6–9 V, 150 g at most).
4 × AA alkaline (107 min, 100 g) or the 2200 mAh LiPo (147 min, 120 g, and the LiPo safety lesson first). The PP3 and the 1000 mAh LiPo run out too soon; 4 × NiMH is under 6 V; 6 × NiMH is too heavy.
Steering: The line drifts left under the robot. To steer back, the robot should… Slow the left motor (or reverse it) and keep the right one going Turning towards the line: the inside wheel slows.
Which is evidence?: Which is the strongest evidence that the design meets a criterion? A test from the table that set the input and recorded the expected result A planned test with a recorded result is evidence; everything else is a feeling.
Stretch and support
Stretch: Proportional steering: slow the inside wheel by an amount that depends on how far off the line it is.
Support: A driver wiring diagram and a two-sensor line-follower sketch to Modify.
Exit ticket
Name the three numbers you checked to choose your battery.
Voltage (in the driver's range), run time (capacity × 80% ÷ current) and weight.
What each step is for
Inquire: the brief: Separating what the design must do (criteria) from the limits it works within (constraints) is the first move of any design brief.
Develop: plan before you build: Choosing the battery against the brief and planning the turn signals before building connects Power and motors to a real design.
Create: build it: Building in the simulator first catches wiring and code slips cheaply; the real build then tests the design against the world.
Test: run your table: Running the test table written in Develop, and recording every result including failures, is the evidence for the evaluation.
Evaluate: against the brief: Judging the design criterion by criterion, with evidence from the tests, is what separates an evaluation from a description.
Where it leads
Other Years 9–10 projects: Automated sorter, Lift.