Day 20 - Popsicle Stick Autonomous Robot (Technological Education)

Computer Engineering - The Popsicle Stick Robot

Nathan Fisher, Bradford District High School

     Often when thinking about trying a robotics project the main factor of intimidation preventing people from getting started is how to create a robotic chassis to hold all of the electronics, sensors and motors that make a robot function.  A metal platform requires machining and metalworking tools, plywood and wooden platforms still work best with access to a shop to create custom cuts and wood materials can still be cost prohibitive for an initial learning experience in a classroom.  That's why I decided to link craft stick crafting and robotics together.  All that is required to shape the structure is a pair of snips to cut the craft sticks and hot glue to reliably assemble the robotic platform.  It is a low-cost and highly creative 'canvas' for robotics solutions.

     Below is a final result of one of the craft stick robots working autonomously.  It encounters obstacles with the bumper sensors.  Depending which bumper circuit was completed, it will turn away from the obstacle it encountered.

Design Process

*Image from: Ontario Technological Education Curriculum 2009 , Page 23

     The creative design process is an integral part of Technological Education.  Creativity, design and innovation are all built into each and every technology course offered in SCDSB. As a teacher, it is a learning experience each and every time a project is assigned since every student can have a different take on how to accomplish the same task.  When we analyse the final design effectiveness, there is never one 100% perfect solution and all solutions have some merit which is very rewarding for students to see.  Creating a project is about maximizing merits while minimizing demerits of design concepts to create the most effective solution for a particular problem.  Different problems benefit from different design concepts being emphasized.

For this project there are 4 specific areas emphasized in the creative design process.

• Robotic platform design
• Bumper Sensor
• Bumper System
• Autonomous Algorithm

Students had to design a bumper mechanism using salvaged supplies that that would connect a circuit when an object is encountered. The main problem to overcome is getting the connection to break again after the bumper is hit.  One solution was to cut a spring from a dried out/broken pen or mechanical pencil. Another solution was to use foam that would expand again after the the circuit bumper was placed.  Finding out whether a bumper was fully functional on a wide range of obstacles took a lot of of testing and adjusting.  If a bumper was hit a certain way it wouldn't trigger, requiring the spring or contact to be adjusted.

Bumper sensor pictured on left.

     The design of the bumper system was another challenge for students.  Functional requirements of the bumper system required it to be held in place and be able to slide back and forth with a low amount of friction while having a wide range of contact to prevent the robot from getting stuck.

Bumper system pictured on right.

The final stage of building the robot is to program the micro controller which controls the input and output.  It is was set to constantly read the bumper switches, and adjust direction away from the object it encountered.

PicAxe microcontroller system pictured on left.

The Learning Experience

     As with all Technological Education classes there is valuable learning for both the teacher and the student. Trying out new projects that will be approached with new ideas or students having innovative takes on old projects that have not been seen before.  The number of potential solutions is near limitless, and we need to enable students' creative problem solving processes by giving them manipulative and constructive opportunities to solve authentic problems.  This is what technological education is. Thus the importance of Technological Education as a physical and practical learning experience for all students from K-12 is clear. And the opportunity to share this experience with students as a Computer Engineering, Computer Science and Robotics teacher is extremely enlightening and rewarding.