MOK week with Ritaharju students

This is the shield that we provided to the pupils.

A group of 12 9th graders from Ritaharjun Koulu have been working at our Fab Lab for around 5 hours per day during the whole week. They have come in company of Sebastian, their technology teacher, who have provided a really valuable help to us while providing support to the pupils with their projects

In this case, the students were given totally freedom oto select their project. During the first day, Antti Mäntyniemi presented the different devices and process that we have at our Fab Lab. In addition, we showed the kids some of the previous projects completed at the Fab Lab (including some robots built by other school groups in the past). After that, we gave them totally freedom to choose whatever they would like to build. The only conditions that we imposed were that they had to use Arduino Uno as a development platform, that they should utilize at least one actuator (to choose among servos, continous servos or piezoelectric buzzer to generate sound) and that they had to build the external mechanics utilizing our laser cutter or if they had previous experience with3D development our 3D printer. In addition, we provided them with an Arduino shield built by a group of first year university students last september. The shield (sright picture) provides supports for 5 actuators (servos, buzzer ...) and a Bluetooth module. All the groups but one utilized the shield in their projects.

We did not define any deadline. Pupils were free to organize their own time. The only condition is that they should have something working by the end of the week. All the groups, in general, organized the time in a similar way. During the first day they had a brainstorm and define their project functionality as well as external appearance. They utilize mainly paper to present their concept to their colleages. During the second and the third day they built the mechanics of their system, mainly using wood and the laser cutter. One group utilized a 3D model, though. During the third and fourth day they started to attach the components (buttons, servos ...) into their projects. They also programmed the Arduino. Finally, during the last day they were mainly making the last minute adjustments and testing their projects.

During the week neither us, nor the teacher, took any leading role. We just provide dsupport to children when they asked for help or when we realized they were stucked with some problem. In addition we taught groups separately how to use the Fab Lab machines (mainly the laser cutter) and provide really short introduction to Arduino platform (description and programming) as well as on how to use Inkscape in order to create 2D models.

All in all, I think the teacher, the students and us got a really positive feeling about the group results. All the groups manage to build a prototype was able to perform basic actions. Not all they groups manage to conclude the projects, though. I think with one extra day all the projects would have been ready. In addition, some of the initial ideas were really challenging, so they had to modify the functionality dinamically to make it more realistic given the time constraint.

Projects descriptions

Useless box

This group built their own version of the Useless Box. Basically, it is a box that contains a mechanism activated by a switch. When a person moves the switch, the mechanism will be switch it back to the initial state. The designed the box utilizing the Inkscape Tabbed Box Maker plugin and cutted on MDF using our Epilog Laser Cutter. In addition they used an extension to cut the hinges (Living Hinges extension).

The switch is controlled by an Arduino Uno hidden inside the box. When activated, a servo moves a semicircular wooden piece that push the switch to its original position. Simple but really effective and appealing.

NOTE:There is one Inkscape extension that contains the most important plugins to work with the laser cutter. Its name is Knox Makers Laser Cutter

Camera rail

The group built a simple camera slider for their mobile phones. It consists on a long gear rack that is moved back and forward by a big semicircular gear attached to a 180-servo. The box which supports the phone is glued to the rack. In addition they have to build a 5mm tall rail to avoid that the gear moves away from the rack. The rack and the gears were built using the Inkscape gears extension. The whole machine was built out of 4mm MDF pieces cut with the laser cutter. Right now the movement is hardcoded in the microcontroller (it basically moves back and forth to a constant speed). However, they were planning to control the position with a mobile phone using a bluetooth connection.

Small Jukebox

These pupils opted to create an Arduino driven Jukebox. They did not used our shield, but they attached directly the components to the Arduino. The gadget core is a 3D-printed box (designed with Autodesk 123D) utilized to accommodate the Arduino board and each one of the four buttons. In addition, they laser-cut the top of the box out of acrylic, with four holes for the buttons. They also laser-cut the name of the songs, activated by each button press, at the top-lid. When a button is pressed the corresponding song, that is hardcoded in the software is played. They utilized a piezoelectric buzzer to play the sound. The four songs of the JukeBox are: Sandstorm, Happy Birthday (actually it plays the Imperial March of Star Wars), Super Mario Bros theme, and Twinkle, Twinkle.

This group created different versions of the Jukebox. In the begining they 3D printed the lid of the box. However, the resolution of the printer was not good enough to present correctly the text so they decided to laser cut it. In addition, the first version of the sofware did not permit to change the song until the current one is finished. I had to help them to implement a new version of the software that it permits a dynamic change of the current song.

Electronic controlled lock

These students designed a simple wooden box utilizing the Inkscape Tabbed Box Maker. The peculiarity is that it includes a cam lock that is opened/closed when the button located at the top of the box is pressed. A servo, makes a wooden cam rotate 90 degrees when a button is pressed. The button and the servo are controlled by the Arduino Shield.

Car with servo controlled direction

This was a really challenging project. They wanted to build a remote controlled car. The idea was to use one continous servo that control the rotation of the back wheels and one 180 servo that acts as a steering wheel. Two gears (one connected to the continous servo and other attached to the back axis) enabled the back wheel rotation. The steering box which control the front wheels were built upon a rack-and-pinion linkage. A servo controlled the pinons which made the front wheels turn. They manage to build successfully the mechanical part of the project. However, they run out of time to implement the software. We just built for them very basic functionality to show that their concept was working.

The rack and the gears were built upon MDF using the Inkscape gears extension, while the outer part of the car was a box designed with the Tabbed Box Maker. Both servos were controlled by the Arduino Shield.