STEM Coding Competition

The basis for successful participation in the competition

First Steps

A small tutorial for the first steps

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Basics ROBO Pro Coding and TXT 4.0 Controller

Important basics about ROBO Pro Coding.

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User Manual TXT 4.0 Controller

A small tutorial for the first steps.

Click here for the manual

The TXT 4.0 Controller has a powerful 32-bit Cortex A7 processor, 512 MB RAM of storage space and 4 GB eMMC, three servo outputs and a touch display that supports gestures, and offers a wide range of new functions

Up to nine additional controllers can be connected to one controller as extensions.

Firmware updates can be downloaded online via the fischertechnik cloud. The ROBO Pro Coding software can be used for graphic programming, as well as using the programming language Python.

The software supports the following operating systems: Windows, MAC OS, Linux, iOS and Android. The app can be installed from any app store.

Other features of the TXT 4.0 Controller include:

8 universal inputs
4 fast pulse counters
4 motor outputs
3 servo outputs
Combined Bluetooth/WiFi wireless module
Control via language recognition
USB host port
Camera port
Integrated speaker
Programming with ROBO Pro Coding or Python, C/C++ Compiler (not included in the scope of delivery)
9V DC power supply

In addition to the TXT 4.0 Controller, the building set contains a variety of actuators and sensors, as well as many different fischertechnik components.

Actuator - Encoder motor

At first glance, an encoder motor looks like a normal electrical motor designed for a 9 V voltage and a maximum current consumption of 0.5 ampere.

However, an encoder motor can do much more. In addition to providing a connection to supply power to the motor, they also include a socket for a 3 pin connection cable that can be used with the so-called encoder to assess the rotary motion of the motor. The encoders on fischertechnik encoder motors generate 3 impulses per rotation of the motor shaft. And because the encoder motor also has a gearbox with a transmission ratio of 21.3:1 (read as “21.3 to 1”), one rotation of the shaft from the gearbox is equivalent to 63.9 impulses of the encoder.

Actuator - Servo motor

A servo motor is a rotary drive or linear drive which allows for precise control of the angular or linear position, speed and acceleration. It consists of a suitable motor, which is connected to a position feedback sensor. Servo motors are used in applications such as robotics, radio-controlled plane or vehicle models or automated production.

Sensor - Camera (image and colour recognition)

The camera is a particularly versatile sensor. The image resolution is 1 Megapixel. The images the camera takes can be transmitted to a PC and displayed on the screen. In addition, the ROBOTICS TXT 4.0 Controller can process the images and use them to detect movements, colours and tracks so that the user can control the robotic model. The camera can be focused by turning the lens.

Sensor - Ultrasound sensor (distance measurement)

A distance sensor is a technical component able to measure the distance between itself and an object. Distance sensors work using light, infrared radiation, radio waves or ultrasound, and use different measurement methods. The fischertechnik distance sensor uses ultrasound. Sound spreads as a wave.

An echo is reflected to the ultrasound source, which is then received as a signal and analysed. The difference between the times at which the signal was transmitted and received indicates the distance between the obstacle and the sensor. The range of the sensor is up to 4 m. The numerical value output corresponds to the distance in centimetres.

Differential gearbox

The adjustment range of the fischertechnik servo motor is mapped in 512 steps in Robo Pro Coding. To fully utilize the steering range, the servo motor must be connected to a servo connection of the started TXT 4.0 controller before assembly. It then moves to its zero position. The servo lever can then be fitted.

In the proposed axle steering setup, the servo motor strikes the chassis from a steering angle of +/- 52°. To protect the servo motor, the lever should therefore only be deflected between the values in this range.

The positions of the servo lever vary with different servo motors. It is therefore advisable to calibrate the zero position and the maximum deflection using variables.

If you are using an individual setup for the stub axle steering, make sure that the servo lever does not hit the servo mount or your chassis. The maximum deflection up to the stop on the servo holder is +/- 58°.

Further information

For further suggestions for your robotics project, you can find various example programs including a configured display or camera in Robo Pro Coding. To do this, do not select an empty template in a new project, but "Example".

You can access the Robo Pro Coding documentation via the following link:

ROBO Pro Coding Books