Robotics - Design, Build And Execute

We have mapped out a project that adhered to the competency based learning standards.
i.e. statement of learning standard, description of the learning tasks and assessment matrix.

The objectives were to design a device that can be programmed to
1. switch on / run the motors,
2. pause at pre-determined intervals,
3. activate the sensors,
4. record the readings,
5. proceed to the next station,
6. repeat the tasks, and
7. download the data eventually to the computer for analysis.

The first step was to work out the gear ratio so that we can slow down the speed.


We utilised 2 sets of gears ( 8 and 40 teeth ) and arranged them so that we can reduce the speed to 1/25th of the original motor speed. See diagram.

Next ,we selected a set of wheels with the appropriate diameter, and we worked out how fast the wheel was turning ( revolution per second ). We attached the angle sensor to one of the wheels, and we recorded a reading of 5 secconds for a complete turn. The wheel had a diameter of 49.6 mm, and the circumference ( product of diameter and pi ) worked out to be 15.6 cm. As a result, we spaced the workstation at an interval of 15.6 cm, as we intended to move the device for 5 seconds and pause.

Light and temperature sensors were attached to take readings from each of the 5 workstations.


We wrote a program to handle this. Upon completion of the datalogging, we proceeded to download the data to the computer for further analysis. The results were presented graphically for ease of visualisation.

The kids were then required to analyse the results and draw on the necessary conclusions. They were successful in interpreting the data and gave correct answers to the light and temperature readings.

Next: Lessons Learned


Keywords: robotics, competency-based learning, datalogging, VBA programming