petersnoek / robot-arm

Robot Arm

Robot Arm is a Lua library for learning how to program. It simulates a robot arm that can grab and drop colored blocks.

The purpose of Robot Arm is similar to that of the classic turtle, but Robot Arm is better suited for slightly more complex program flow. Where the turtle mainly teaches you that the order of instructions is important, Robot Arm allows and encourages you to use loops, functions and data structures to build your own operations and algorithms.

The number of operations Robot Arm supports is intentionally limited. You can (and should) build more complex operations yourself from the basic building blocks.

Prerequisites

• wxLua

Robot Arm is written to be used in ZeroBrane Studio. It should/might work without ZeroBrane Studio, but that hasn't been tested yet.

Installation

To use Robot Arm, just copy robot_arm.lua (from the src folder) to the folder that contains your Lua libraries.

Alternatively, you can copy robot_arm.lua to the same folder your program runs in, but then you have to make a copy for each program you write.

Usage

Simply add require "robot_arm" to the top of your Lua file.

The robot arm understands six instructions: move_left(), move_right(), grab(), drop(), scan(), and wait(). You can also set the robot arm's speed on a scale of 0 to 1. If speed is equal to 1, you won't see any animations.

Levels

Robot Arm comes with a couple of build-in levels. You can use load_level(name) to load a build-in level, where name is "exercise 1", "exercise 2", "exercise 3", etc. Note that these build-in levels are subject to change.

You can also create a set of random blocks with random_level().

Example

require "robot_arm"

robot_arm.speed = 0.85
robot_arm:random_level()

robot_arm:grab()
robot_arm:move_right()
robot_arm:drop()
robot_arm:move_right()

robot_arm:wait(2)

robot_arm:grab()

if robot_arm:scan() == "red" then
  robot_arm:move_left()
  robot_arm:move_left()
end

robot_arm:drop()

Known issues

• You must use the name robot_arm when you require the library. This means that library must be on Lua's library path, because something like require "libs.robot_arm" won't work.
• In ZeroBrane Studio, you can't use Robot Arm from the local console yet.