The LEGO Galaxy Explorer is amongst one of the most popular sets of all times. In 1980 LEGO published the Idea Book 6000 that contained an alternative build for the Galaxy Explorer. The building instructions were sketchy at best. I built the Galaxy Explorer 6000 model for the Moonbase 42 at the Christchurch Brick Show 2015 and I also created an LDD file for it. The building instructions are available here. It has been great fun to re-create this spaceship from my childhood. I hope you enjoy it.
Here is the original 497 Space Explorer in all its glory:
This LEGO great ball contraption consists of a module that sorts the balls by its color and a train module that returns the balls to the start. Both modules use Mindstorms EV3s to control the motors. The train EV3 controls and original LEGO RC Train motor using a DIY cable.
Harry Davis and me built a cable to connect a LEGO Power Functions (PF) motor to a Mindstorms EV3. The goal is to enable the EV3 to control PF motors. In particular I wanted to control a RC train motor through an EV3.
LEGO produced a cable (8528) to connect old motors (RCX) to the NXT, but it is no longer in production. You can still get them through Bricklink, but it will cost you dearly. You still need a PF extension cable to convert the old motor plug (RCX) to the current PF plug.
Firgelli produced a cable that allowed you to connect an modern PF to NXT directly, but it is also no longer in production.
There are two more solutions but both are more complex and costly. First, you can use the PF Mate from Mindsensors (currenlty $35). It sends IR signals to the IR PF receiver and thereby allows you to control motors even at a distance. The second option is the GlideWheel PF (currently $38) that directly connects a PF motor to the EV3. It also features a rotation sensor so that you can control the PF just like you would control a Mindstorms encoded motor. Both of these solutions offer a great functionality but they are also expensive, in particular since the components necessary for a custom made cable only costs a few cents.
At Amazon you can get a book Make: Lego and Arduino Projects: Projects for extending MINDSTORMS NXT with open-source electronics that will show you how to do such projects, but for now it is time to pull up our sleeves and do it ourselves. TechnicRobot already showed that it can be done but detailed instructions were not yet available. We also built a casing for our cable so that it can be easily integrated into your model. Here is the final result:
And here is a video that shows our solution at work:
Dexter Industries offers the DLight for LEGO Mindstorms. It allows you to control four full color LEDs through a sensor port of your EV3 or NXT. The first thing to do is to set the toggle switches on each LED to a unique address, so that you can control each LED individually. In the NXT-G environment you can still decide to control all of them at the same time if desired. The biggest nuisance is that only the first LED can use its red component. The other three cannot show any red light. Dexter acknowledges this bug in its forum and offers refunds. It is ridiculous that Dexter does not warn its customers on its product page, in particular since they do not intend to fix this problem.
that will show you how to do such projects, but for now it is time to pull up our sleeves and do it ourselves. 