kids-toy

A race car that simulates a Formula 1 car can be made using the LEGO MINDSTORMS Education EV3 (45544) educational set. The driver sits in the car and holds on to the steering wheel. The machine is remotely controlled from an Android smartphone.

I used the EV3 Numeric Pad app to control the car (see picture below). The application allows you to make control according to your own algorithm. Here are the steps to follow to drive this race car with EV3 Numeric Pad:

• • • • Launch the application EV3 Numeric Pad and connect it via Bluetooth to EV3.
      • Run the demo on the EV3 (be sure to set the front wheels straight before running).
      • Can be managed.

How the app works EV3 Numeric Pad next: when you touch the blue rectangle and move your finger over it, you thereby move the red target along it. During this time, the app continuously transmits the target’s coordinates (in the X and Y axes) to the EV3 Brick. The x-coordinate is transmitted in the range from -100 to 100 to the mailbox named «x», and the y-coordinate is also transmitted in the range from -100 to 100, but to the mailbox named «y» (top left displays the current numbers transmitted by EV3).

Demo Program racing-car.ev3, which you can download below, reads the coordinates from the «x» and «y» boxes and converts as follows: the x-coordinate is converted to front wheel turns to the right and left, and the y-coordinate is converted to rear wheel speed. As soon as you lift your finger from the screen, the red target returns to the center of the blue field, the EV3 Brick is given coordinates 0, 0 and, accordingly, the front wheels return to a straight position and the rear wheels stop.

The bottom bar works similarly to the top square box, but it passes values ​​from -100 to 100 to a mailbox named «z». If you touch here with your finger to the left or right of the center, the demo program will make the car horn.

Instead of a program EV3 Numeric Pad you can use its more advanced analogue EV3 Numeric Pad+ (see the picture below), which has 4 additional buttons, by clicking on which, you can program additional actions. The numbers of the pressed buttons will be sent to the mailbox with the name «w». Here is what you can try to program yourself when pressing additional buttons:

• • • • Assistance to the driver when turning: after pressing the button, the car independently makes a 180-degree turn, alternately moving forward and backward and turning the steering wheel left and right.
      • Assistance to the driver in parking: set the car near the place where you want to park, press the programmed button, and the car will park itself.
      • Signaling: setting and disarming — while the car is armed, it cannot drive, and when an obstacle is detected near the distance sensor, the siren turns on and the LED starts flashing red. You can also connect a gyroscope and use it to determine that the guarded car is stationary, and as soon as someone moves the car, also turn on the alarm.

In addition to being in the program EV3 Numeric Pad+ there are additional buttons, here you can choose between two options for mailbox names. These can be boxes named ‘w’, ‘x’, ‘y’ and ‘z’ (default) or ‘a’, ‘b’, ‘c’ and ‘d’. Those. You can program two remotes at once in one.

Files:

In addition to the first version of the car, you can make a version of the car with increased movement speed. In the high-speed version, gears have been added, due to which the car will lose power, but will be able to go 5 times faster. The only difference in assembly is the mounting of the rear wheels (steps 18, 24, 25 and 26 are different, and step 29 becomes steps 29 — 35 in the speed version). For this version, you need to use a different demo program.

Another way to control a racing car is shown in this video:

Here is the first-person control of the racing car using a smartphone, tablet and the RoboCam application. How to install and use this application, read the articles. You can download ready-made RoboCam settings for controlling a racing car here.