The effect of visual and text interfaces in teaching robot programming

Programming is a popular subject in education and experts emphasize the importance of teaching programming to the children in the high school or even earlier. In European countries, ministries of education give efforts to integrate programming education to school curricula. Some of these countries already have programming classes in high schools and consider to give programming class to younger students. In this respect, methods of the programming education is an important subject and deciding on more successful methods is the problem of this area. In this work, we address this problem and compare different programming interfaces to each other. While teaching programming, we use an educational robot to increase the understanding of the programming environment. Thymio, which is the educational robot we choose, does not require any knowledge of electronics beforehand and it is in no need of hardware related constructions before the programming. Therefore, when using Thymio our students can focus only the programming part and use different prebuilt functions of the robot. Thymio is simple structured, has a special programming language and development environment for different operating systems and more importantly it is more accessible and suitable for children because it was made of simple and limited number of sensors and actuators. Also Thymio supports two different programming interfaces. First one is text based programming language which is called Aseba Event Scripting Language (AESL) and the other is icon based programming interface which is called Visual Programming Language (VPL). This study focuses on the programming interfaces and their effects on the performance of programming education. Therefore, we use text programming and visual programming interfaces to teach programming to students. VPL is a purely icon based programming interface and it does not have keywords. Robots can be programmed using only drag and dropping the required icons on the interface. Students do not need to use keyboard and they are not required to know any technical details. On the other hand, AESL is keyword based text programming language which has syntax rules with different keywords. Basic programming features such as variables, decision mechanism, loops etc. are included in the language. It has been designed as event based language to be compatible with robot events. To be able to use AESL interface, students must know basic English and must understand English keywords. To test the effect of this requirement, in addition to original AESL interface we developed an equivalent Turkish keyword based AESL, which we call TAESL. In TAESL, all the keywords and native functions are replaced with Turkish keywords. To be able to do this, we modify the development environment and robot's firmware. To test our interfaces with the students, we also prepared a curriculum for teaching programming with a robot. We prepare three lessons according to text programming and visual programming interface structures and Thymio's features. First lesson generally covered introductory subjects to programming and development environment. In the second lesson, we focused on the decision mechanism with minor sensors and actuators of Thymio. In the third lesson, we covered complementary elements to robot components and programming features. In addition to new topics, we have reinforced previous topics to reach a better understanding of algorithms as well as introducing new topics. Our teaching strategy as well as the consequent assessment experiments focused on basic programming subjects. We kept the lectures rather simple, so that we can ignore effects of personal skills and cognitive levels of the students. Also the languages, VPL and AESL, do not need long code portions to control the robot; so we avoid using complex algorithms and long code parts. Almost all of the examples consist of a few lines of code. This minimizes the complexity of teaching, thus we ignore the algorithm creation, debugging and testing effects on our evaluation. In order to reduce the effects of lecturer, we prepare in the form of recorded lectures based on video for each lesson. In addition to that, we organize the lectures as one to one training, thus we minimized the effects of the classroom environments in teaching. Each lecture is planned to be a traditional 45-minutes long session. First 20 minutes of the lesson is devoted to the lecture part. In this section, students watch the lecture videos and ask their questions. Next 10 minutes are reserved for practicing with the robot freely. The final 15 minutes section is dedicated to the exam part. In the evaluation phase, collected codes are tested by our team in predesigned evaluation environment which has obstacles and cliffs at necessary locations. Each objective is assessed in the given order and the student is considered successful only if the code produces the expected outcome. In our experiments, 32 students, within ages of 7 to 24 with an average 14.3 and standard deviation 5.25 participated. The majority of the students had no experience with programming before and rest of them had barely some experience on programming. We divided students into 3 different groups, students who studied visual programming (Group 1), students who studied text programming (Group 2) and students who studied text programming after visual programming (Group 3). According to the results of experiments, students who studied with visual programming have been more successful than students who studied only text programming. This is an expected result because visual programming is faster and simpler to program. So, it can be said that the visual programming languages are better for learning programming. When we compare the performance of the students who studied only text programming, with the performance of the students who studied visual programming first and then text programming, we observed that students who studied text programming after visual programming have been more successful than students who studied text programming only. This comparison shows that learning programming with visual languages helps to learn text based programming languages later. Another performance criterion in our tests is the time spent on each interface. While time spent on the visual programming interface is always less than the others because of the simplicity of the visual programming, the effects of the visual programming languages can be seen on the time spend for programming on between text programming after visual programming and just text programming interfaces. According to these result we can say that learning programming with visual languages helps to adapt text based programming faster. We also compared the results of the students who study with original text programming to the results of the students who study with TAESL. In our test results there is no significant difference between the success rates of original AESL and TAESL. Average success rates is nearly identical in original AESL and TAESL. In conclusion, we used different programming interfaces to teach programming using robots and compared the results of the experiments. According to result of our experiments, visual programming languages are found to be easier and quicker to learn. In the experiments, using visual programming students had higher success rates overall. In addition to that, when learning text programming, if students have visual programming background before, they had more successful results on learning text programming concepts. So, we verified that if visual programming languages are used for learning programming first time, students can adapt to other programming languages easier. Also, according to our experimental results, using a mother-tongue based programming language does not have any effect on the learning of programming.