Block Programming - Using Loops

Block programming, an intuitive and visually pleasing approach to coding, has revolutionized the way we teach robotics, particularly to young learners. Among the fundamental concepts that students grasp through this method is the concept of 'loops'. When coupled with devices like an IR (Infrared) Remote, it opens up a myriad of practical, hands-on learning opportunities, making the abstract concepts of coding come alive in the real world. In this essay, we'll explore the use of loops in block programming specifically focusing on the IR Remote scenario.

Loops, a cornerstone of programming logic, allow us to execute a block of code repeatedly until a certain condition is met. In block programming, two commonly used loops are 'repeat' (similar to 'for' loop) and 'forever' (similar to 'while' loop). These can be used creatively to control robotics components using an IR Remote. For example, we can design a block program that commands a robot to move forward continuously until the 'STOP' button on the IR Remote is pressed. The 'forever' loop runs an 'if-else' block checking if the 'STOP' signal is received. If not, the robot keeps moving. This makes an abstract concept like an indefinite loop tangible and intuitive to learners.

Another key loop in block programming is the 'repeat' loop, which is analogous to the 'for' loop in traditional text-based programming. This loop repeats a block of code for a specific number of times. To illustrate its application with an IR Remote, consider a scenario where a robot is programmed to flash its LED light five times when a specific button on the IR Remote is pressed. Inside the 'When IR Remote received = "START"' block, we place a 'repeat 5 times' loop, turning the LED on and off with one-second intervals. This hands-on approach brings the theoretical 'for' loop concept into the physical world, strengthening understanding through application.

But the real power of loops in block programming shines when we combine different types of loops and conditionals. Imagine creating a robot that can be manually controlled to move in four directions using an IR Remote. In the 'forever' loop, we can use nested 'if' statements inside. Each 'if' block checks if a different directional button (UP, DOWN, LEFT, RIGHT) on the IR Remote is pressed and moves the robot accordingly. This is an excellent demonstration of how loops and conditionals can interact to create complex behaviours in robotics.

Block programming with devices like an IR Remote makes learning about loops engaging, interactive, and fun. The tactile feedback from the IR Remote, combined with the visual feedback from the robot, truly brings the loops concept to life. By physically controlling the repetitions of actions using an IR Remote, students gain a deeper understanding of the significance and application of loops in programming. This solid foundation prepares them for more advanced studies in robotics and other fields of computer science.

Example 1: Forever Loop with IR Remote STOP signal

forever {

if (IR_Received == "STOP") {

stop robot

} else {

move robot forward

}

}

Example 2: Repeat Loop with IR Remote START signal

when IR_Received == "START" {

repeat 5 times {

turn LED ON

wait 1 second

turn LED OFF

wait 1 second

}

}

Example 3: Nested If Statements with Directional Buttons on IR Remote

forever {

if (IR_Received == "UP") {

move robot forward

}

if (IR_Received == "DOWN") {

move robot backward

}

if (IR_Received == "LEFT") {

turn robot left

}

if (IR_Received == "RIGHT") {

turn robot right

}

}