This paper investigates using educational IoT in group of students. There is formal investigation of IoT system approach presented as transition systems and their composition which presented as Petri net with next liveness checking. Paper describes architecture of IoT system which is implementation of Petri net. Nowadays IoT devices is popular and can be used as IoT for mobile phones, smart homes, automotive technologies. There is a good opportunity for using IoT in education curriculum. This paper exposes using IoT technologies in education, especially model of interaction between IoT and end-users, and realization of model by using system architecture. This paper has a contribution: model of interaction between IoT and end-users which exposed as Petri net with liveness checking which is result of multiplication transition systems of each aspect of interaction and system architecture of implementation of Petri net. Section II provides a literature review oof using educational IoT. Section III introduces using IoT in curriculum and described initial information about IoT system. Section IV provides transition system and Petri net definitions, investigates liveness of Petri net presented as multiplication of transition systems. Section V presents system architecture of Petri net implementation. Section VI describes conclusions and Section VII - references.
There are plenty examples of using IoT in education curriculum with Lego Mindstorm. There is
Robolab programming tool for Lego Mindstorm analysis of using IoT for learning programming
languages by students which take a part in Lego IoT building blocks, decomposing and investigation
of educational task given, running program [
Different interaction between system architecture aspects can be presented by Petri net. Current
paper describes model interaction by using transition systems of each aspect by example of model of
working with graphic processing (GPU) systems where working GPU cycle is decomposed by parts
and presented as transition systems with further transforming to Petri net with liveness checking[
Let’s describe overall view of using IoT in education curriculum. Let’s assume that there is theoretical educational IoT device which is controlled by student’s command in moment of solving educational task. This IoT device illustrates task invocation, which helps student understand correctness of command according to task. Task for student is generated by task service and student solves this task by means of user interface service which handle user task’s input and user interface service interacts with IoT. Also, IoT can be used in group of student which can share common task generated from task service – task generates accordingly to data collected for group of IoT devices paralelly. There are three aspect of interaction: user service – gets task from task service, interacts with user input, transform input to task command and sends to IoT device, task service – generates task for students, collects information about each IoT device and generates task according to information collected. Task service controls parallel invocation of task of all IoT devices assigned IoT – device which performs each command obtained by user interface assigned. In conclusion, user service, task service and IoT can be presented as transition system in the next chapter.
Let’s introduce transition systems and Petri net [
Let’s 1, … , are transition systems where = ( , , , , 0), = 1, … , . Constraint of synchronization is subset of set ( 1 ∪ { }) × … × ( ∪ )\{( , … , )} where is identical transition which is absence of any action in transition system. Elements of set are global transitions. If = ( 1 … ) ∈ and ≠ then transition system takes a part in the transition . Tuple = ( 1 … , ) is multiplication of transition systems 1 … , which are multiplication components of . Global transition = ( 1, … , ) is modeling possible transition to 1 … . If transition = then transition system doesn’t take a part in the global transition .
Petri net ( , , , 0) describes multiplication = ( 1, … , , ) of transition systems = ( , , , , 0) where ∩ = ∅ with ≠ . , = 1,2, … , if = 1 ∪ 2 ∪ … ∪ , = , = {( , )│ ≠ & = ( )} ∪ {( , )│ ≠ & = ( )} for some = {1,2, … , } where defines -th component ∈ , 0 = ( 01, 02, … , 0 ) . Semantic of multiplication of transition systems and semantic of Petri net which is illustration of this multiplication, accords in sense of sequence of global transitions 1, … , is global history of multiplication of transition systems only in case of using allowable sequence of results of transitions for Petri net.
Let’s abbreviate transition system as TS and there are: 1 – IoT 2 – user interface service 3 – task service Interpretations of states and transitions from fig.1 for 1 are next: 0 – waiting command from 2 1 – fetching command from 2 1 – command fetched is stated and is ready to use data from command 2 – send command to controller to start 2 – controller started command invocation 3 – get command invocation result 3 – result is fetched and prepared to return to 2 4 – result of invocation is sending to 2 4 – result of invocation is sent and there is nothing to do.
5 – transition to 0 9 – go to initial state: wait for user input
After building Petri net there is a task of checking correctness of model – let’s check liveness of Petri net. For liveness checking it needs to find solution of equation ∙ = 0 where A is incidence matrix for this Petri net on fig. 5.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Figure 6: solution of ∙ = 0 All transitions of Petri net are covered by positive invariant values so Petri net is viable.
Task service generates one common shared task parallelly for group of IoT devices. Common task means one common task with specific context of each IoT device. Specific context can have task difficulty, IoT configuration, actual state of IoT.
According to transition systems above there is system implementation: Task service transition system is implemented as task service User interface service and IoT transition systems are implemented into education IoT system.
There is the scheme for implementation on fig. 6:
Let’s view education IoT implementation: it can consist of educational robot as IoT, as Wi – Fi web server and mobile phone, as user interface service, as Wi – Fi client. Mobile phone is used as illustrative example of device with user interface. They have JSON restful communication on fig.7. Via mobile phone student can send command to robot to change location and task service generate tasks for students and can check command from mobile phone before sending to robot.
Let’s see IoT robot inner components: there is a power source, which gives a possibility to use robot IoT autonomously, Wi – Fi web server module which communicates with mobile phone as user interface service via JSON protocol, microcontroller which controls command invocation, engine module with motors which can move robot to other location on fig. 8. Robot can have functionality of changing location. Group of students solves common changing location task with purpose to impove programming skills. Task service controls all IoT devices assigned to common task and generates new task to each IoT device accordingly.
Task service can be implemented as web – server which generates, checks task for mobile phones for students. Web service interacts with mobile phone via JSON restful protocol and web – service can support parallel connections which allow to do common task in group of students as showed of fig. 9.
Web service uses database as data source for keeping all actual information data about all IoT assigned to task service.
Let’s see implementation of Petri net as interaction of systems.
User interface (mobile phone) waits for user input, which is command programmed for IoT robot.
After user input user command in fetched and going to be sent to task service via JSON protocol User command is sent to task service web server via JSON protocol and wait for task service response
Task service web server sends the command to database to get actual info about other IoT Task service web server got database result about the command invocation Task service web server return result with the command to user service (mobile phone) User service sends the command to IoT robot Iot service (IoT robot) obtains a command via JSON protocol by means of Wi – Fi controller IoT service does the command by using IoT robot’s components IoT service sends to User interface the command invocation result User interface service obtains a result from IoT service User command is sent to task service server and wait for task service response Task service obtains the command Task service sends the command to database to get actual info about other IoT and generates new tasks Task service got database result about the command invocation and new task Task service return result with the command to user service (mobile phone) User interface service shows result to end users and waits for next input
Implementation of IoT system is similar to Petri net transitions sequence.
There is education system for possibility to solve common task in group of students which can be decomposed into three transition systems IoT, user interface service and task service. After Petri net, as multiplication of three systems, is used for checking liveness of IoT educational system model. This model can be implemented as IoT robot as IoT transition system, mobile phone as user interface service and task server as task service. This system supports parallel work which allows generate one common task for group of IoT devices.