MBC Ranger 2-Way × EV3-G (EV3 Lab software)

Read the Ranger with EV3-G in three steps

In the EV3 software (EV3-G), the Ranger 2-Way shows up as a LEGO Infrared Sensor. So you do not import a library: you read it with the Infrared Sensor block in the right mode. Work through the steps on the left and the blocks on the right grow with you. These pictures were taken in EV3-G after opening each program (100% size, English interface), so they look exactly like the software.

1

Start: Start block + Loop

You need to read the sensor again and again. A new program already has the green Start block. Attach an orange Loop block after it and put a Wait block inside, so it reads every 0.1 seconds.

  1. Open the EV3 software (EV3-G) and make a new project.
  2. Drag a Loop from the orange Flow Control tab and attach it after the Start block (it repeats forever by default).
  3. Drag a Wait block into the loop, choose the Time mode and set it to 0.1 seconds.
2

Meet the reading blocks (Infrared Sensor)

On the EV3, the Ranger 2-Way shows up as a LEGO Infrared Sensor. Drag the Infrared Sensor block from the yellow Sensors tab and choose the mode at the bottom left of the block; the number at the top right is the port: choose 1 (the sensor is in port 1). The product puts different values in different modes:

BlockWhat you getRange
Measure → ProximityAverage distance0 to 100 (1 step = 1.2 cm, 100 = nothing in front)
Measure → Beacon, channel 1: HeadingLeft eye distance0 to 100 (1 step = 1.2 cm)
Measure → Beacon, channel 1: ProximityRight eye distance0 to 100 (1 step = 1.2 cm)

Use blocks of only one mode in a program (Proximity, Beacon or Remote). Every mode change makes the EV3 pause for about 1.1 seconds.

3

Show it on the EV3 screen

Use the Text block from the red Data Operations tab to join a name (for example POS) and the reading, then feed it into the green Display block (mode Text → Grid, Y = the line). The yellow and orange lines are data wires: drag one from the sensor to the Text block, and one from the Text block to the Display block. Put a "Display → Reset Screen" block before the loop. Click a function and the blocks and result change to its example.

Sensor simulator (seen from above, front of the robot facing up): drag the left and right obstacle distances and watch the output on the right change

The simulator is only a sketch: it turns the obstacle distance on screen into the EV3 number (cm × 100 ÷ 120); it is not the sensor's own method.

Block example for each function

Every value EV3-G can read has a small program you can copy (sensor in port 1). Press "Try it" to jump to step 3.

What EV3-G cannot read: distances in millimetres, the nearer distance, laser start-up and fault status, device ID and firmware version. The modes 3 to 6 added in firmware v4.0 (for example millimetre distances, bitmaps, connection state, device ID) cannot be read with EV3-G blocks either. For these, use Pybricks (the EV3 needs a different microSD card) or clev3r.

Things to know

  1. Plug the sensor into port 1. If you use another port, change the port number on the block. Switch the EV3 on first, then plug in the sensor; if the number never changes, unplug it and plug it in again.
  2. Use one mode per program. Each change between Proximity, Beacon and Remote makes the EV3 pause for about 1.1 seconds, and a racing robot can lose control.
  3. When the sensor is unplugged: the EV3 cannot read it, the number becomes "not a number" and the screen shows ----. Each reading also waits about 1.2 seconds. The program does not stop, and it works again when you plug the sensor back in.
  4. Units: on the EV3, 1 step = 1.2 cm and 100 = nothing in front (or that laser failed). For millimetres use Pybricks or clev3r (modes 3 and 5).
  5. Left and right: stand behind the robot and look forward; the left eye is on the left.
  6. English interface: the block icons are the same in other languages; only the menu text differs.
  7. For complete projects (line following, avoiding obstacles, driving …) see the EV3 examples page; most examples have an EV3-G file to download.