Educator Vehicle (retail kit version)
The 'educator vehicle' or 'driving base model' is the official Lego standard model for the 'robot educator' exercises included in the educational version of the EV3 software. The building instructions for the model can be viewed or downloaded HERE (thank you, Laurens Valk!). Those build instructions are for the education version of the EV3 kit. The education and retail versions are somewhat different so the educator vehicle cannot be made with the home (retail) version of the EV3 kit without some modifications and compromises.
This page shows you how to modify the educator vehicle build instructions in order to be able to build the vehicle with the home (retail) edition of the EV3 kit. Even if you follow these instructions there will be significant differences between the home version and the educational version of the vehicle:
- In the home version you will have to replace the ultrasonic sensor with the infrared sensor, which measures distances less accurately than the ultrasonic sensor. You will have to modify your programs to take into account the differences between these two sensors. Of course, it is also possible to buy the ultrasonic sensor separately.
- You will not be able to use the gyro sensor with the home version unless you purchase it separately
- The wheels and tires that are included in the home kit are smaller than those in the educational kit. Specifically, the tires of the home kit have a diameter of 43.2 mm rather than the 56 mm of the tires in the education set, which means that the body of the home version of the educator vehicle will be lower (about one beam-height lower) than for the educator vehicle based on the educator set. This should not be a big problem but you may also need to make adjustments to your programs to take into account this difference.
The build instructions are actually a composite of several parts:
- Base vehicle (45 steps)
- Vertical Color sensor attachment (6 steps)
- Horizontal Color sensor attachment (6 steps) (obviously, you won't use the light sensor vertically and horizontally at the same time)
- Touch sensor (6 steps)
- Ultrasonic sensor attachment (8 steps) (you will replace the ultrasonic sensor with the infrared sensor)
- Gripper attachment (20 steps)
- Gyro sensor attachment (8 steps)
Here are the modifications you need to make. In the photos below, the cables are sometimes not included for reasons of clarity. The colors of the pieces shown are not necessarily those of the pieces of the home (retail) set.
Base vehicle sequence
- In step 3, replace the 4-length axle with a 3-length axle and ignore the red piece.
- Similarly, in step 16, replace the 4-length axle with a 3-length axle and ignore the red piece.
- Ignore steps 24 to 34 and replace them with the instructions below
- Prepare the following pieces (paying no attention to the color of the pieces).
- The axle lengths are 3 and 7 units.
- Use the following images to guide you as you assemble the parts:
- In step 38 you will of course use the smaller wheels that come with the home edition.
Vertical color sensor attachment sequence
- You could attach the sensor like this:
Horizontal color sensor attachment sequence
- You could attach the sensor like this...
- ...or simply like this
Touch sensor sequence
- You could attach the touch sensor as shown for the color sensor in the previous photo, like this:
Ultrasonic sensor attachment sequence
- The infrared sensor has the same form factor as the ultrasonic sensor so you can simply follow the instructions given in the PDF, replacing the US sensor with the IR sensor. The clearance between the IR sensor and the (smooth) floor will be about 2mm. If you want more clearance you could attach the IR sensor like this:
Gripper attachment sequence
- You should be able to construct this attachment without any modifications. Here are two photos of the home version of the educator vehicle complete with gripper attachment, color sensor and touch sensor. It's even possible to attach the IR sensor, the gripper attachment, the color sensor and the touch sensor at the same time! (In these two photos, the touch and color sensors have accidentally swapped places.)
Gyro sensor attachment sequence
- Since the home edition of the EV3 kit does not include the gyro sensor you can ignore this section.