 Hello, everyone. I am Ashish Zawalka working as a student professor in Department of Mechanical Engineering at Walton's Institute of Technology, Singapore. Today we are learning about robot programming languages. Let's look into it. Learning outcome. At the end of this session, students will be acquitted with generations of robot programming languages. Robot Languages. The previous session on robot programming was devoted to the types of task commands that can be implemented on a robot. The current session will be concerned with textual languages for robot programming. Most of the robot languages implemented today use a combination of textual programming and teach pendant programming. The textual language is used to define the logic and sequence of the program while the specific point location in the workspace are defined using teach pendant control. This can be thought an offline online programming method in the sense that the program itself can be written offline with the textual languages while the points must be defined online with the teach pendant. In our discussion, a textual programming language will be described which represents a composite of the available commercial robot languages. Textual Robot Languages. The first textual robot language was WAVE developed in 1973 as an experimental language for research at the Stanford Artificial Intelligence laboratory. Research involving a robot interface to a machine vision system was accomplished using the WAVE language. Development of a subsequent language began in 1974 at Stanford. So the language was called AL and it could be used to control multiple arms in task requiring arm coordination. Many of the concepts of WAVE and AL went into the development of the first commercially available robot textual language that is VAL, Victor's Assembly Language. After Victor's Saint Man, VAL was introduced in 1979 by Unimation for its Puma Robot series. This language was upgraded to VAL2 that is VAL2 and released in 1984. Work in robot language development was also taking place at the T.J. Watson Research Laboratory of the IBM Corporation. It was around 1976. Two of the IBM languages were ATOPAS and AML. The second of which has been commercially available since 1982 with IBM's robotic products. Both of these languages are directed at assembly and related tasks. Some of the other textual languages for robots that should be mentioned include RAIL Rail which was introduced in 1981 by Atomatics for Robotic Assembly and ARC welding as well as Machine Vision. Similarly MCL Manufacturing Control Language was developed under US Air Force sponsorship by McDonnell Douglas as an enhancement of the APT that is Automatically Programming Tooling and similarly HELP helped available from the General Electric Company under the license from the Italian firm DEA. Now coming to Generations of Robot Programming Languages. The textual robot languages possesses a variety of structures and capabilities. These languages are still evolving. In this section, we identify two generations of textual languages and speculate about the what a future generation might be like. These are first generation, second generation and future generation languages. So let us move to first generation language. The first generation language use a combination of command statements and teach pendant procedures for developing robot programs. They were developed largely to implement motion control with a textual programming language and are therefore sometimes referred to as motion level languages. Typical features include the ability to define manipulator motions, straight line interpolation, branching and elementary sensor commands involving binary signals. They can be used to define the motion sequence of the manipulator like move. They have input output capabilities like weight, signal. They can be used to write subroutines like branch. Now think which method is easier for programming a robot that is teach pendant or textual programming. For writing a program of low to medium complexity, sharp person would likely find the teach pendant methods of programming easier to use. Whereas people with computer program experience would probably find the first generation language easier to use. The real language that is VAL is an example of a first generation robot programming language. Limitations. Common limitations of first generation languages include inability to specify complex arithmetic computations for used during program execution, inability to make use of complex sensors and sensor data, a limited capacity to communicate with other computers and these languages cannot be readily extended for future enhancement. Second generation languages. Now coming here the second generation languages overcome many of the limitations of the first generation languages and add to their capabilities by incorporating features that make the robot seem more intelligent. These languages have been called structured programming languages because they possesses structured control constructs used in computer programming languages. Commercially available second generation languages include AML, RAIL, MCL and VAL2. The features and capabilities of these second generation languages can be listed as follows. Motion control. This feature is basically the same as for the first generation languages. Motion control capabilities in some of the second generation languages goes beyond the previous generation by including more complex geometry problems than straight line interpolation. For instance MCL language includes many of the geometric definition features contained in an APT for example like lines, circles, planes, cylinders etc. Advanced sensor capabilities. Now here the enhancement in the second generation languages typically include the capacity to deal with more than simple binary on-off signals and the capability to control devices by means of the sensory data. Advanced sensor capabilities include the use of analog signals in addition to binary signals and the ability to communicate with devices that are controlled by the signals. For example control of the gripper. So in first generation language it involves commands to open or close the gripper but in second generation languages it permits the control of censored grippers which can measure force, pressure during closure against the object. Limited intelligence. This is the ability to utilize information received about the work environment to modify system behavior in a programmed manner. Instead of merely repeating the same motion pattern over and over with a slight difference for different product configuration the robot has capacity to deal with irregular events that occur during the work cycle in a way that seems intelligent. The intelligence is limited in the sense that it must be programmed into the robot controller. Now the lastly communications and data processing. Second generation languages generally have provisions for interacting with computers and computer databases for the purpose of keeping records, generating reports and controlling activities in the work set. The communication capabilities would be used for maintaining production records on each product, generation, each product, generating performance reports and similar data processing functions. Future generation languages. Future generation about languages will be involved a concept called world modeling. In a programming scheme based on world modeling the robot processing knowledge of the three-dimensional world and is capable of developing its own step-by-step procedure to perform a task based on a stated objective of what is to be accomplished. According to this definition there are two basic ingredients of a programming language based on a world modeling system. The first is that the robot system has in its control memory a three-dimensional model of its work environment. This model includes the robot manipulator itself, the work table fixtures, tools, parts and so on. World model might be generated either by inputting three-dimensional geometric data into the control memory or by providing the robot with the capacity to see the work environment and properly interpret what it sees. In a second case the robot develops its own three-dimensional model of the workplace. The second ingredient of the capacity for automatic self-programming the system, the objective and the system develops its own program of actions required to accomplish the objective. It should be possible with future generation languages to accomplish robot programming completely offline without requiring the need for a teach pendant to physically show each point in the program to the robot. In the next part of this session we will be learning about robot language structure, elements and functions. These are the references for lecture presented. Thank you.