The paper proposes a model for Smart Factory's elements informational interaction and organizing their functioning using smart contracts. An approach for modeling Smart Factory is based on the Enterprise Resource Planning organizational strategy, which assumes the division of the manufacturing process into modules, and is focused on continuous balancing and resource optimization. The proposed model includes a common Central Computer, modules for resource managing, agents responsible for operations, and task executors. The Central Computer receives a response from the External Environment, sends it to resource managing module, which determines the required amount of resources for the manufacturing operation and distribute tasks to the executors. To increase the production performance, two types of smart contracts are introduced: the former for defining a contract between the Smart Factory and the environment, and the latter for the production process organization. The integration of smart contracts into the production process allows to automate decision-making and control procedures, reduce the probability of manufacturing a low-quality product, and diminish the production costs.
Smart contract is a block of computer code in which the agreement on the transaction between the parties are formed. After the parties established the contract, it is maintained in the blockchain and comes into force. Such contracts are used in various fields such as finance and insurance, e-commerce, taxation and auditing, etc.
The integration of smart contracts and blockchain technologies into various economy sectors
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Decision-making and execution control automation [
The contribution of this work is twofold. First, we propose a Smart Factory model, which is described in the Enterprise Resource Planning organizational strategy context. The model divides manufacturing process into modules, and is focused on continuous balancing and resource optimization. In addition, we integrate smart contracts into Smart Factory elements’ informational interaction model, which allows to regulate the relations with the External Environment and between Smart Factory elements’.
Internet of Things (IoT) access control is a critical issue. In [
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In this paper we consider centralized factory elements informational interaction model. Under
a centralized factory we mean a production model that has one common center responsible for
communication with the External Environment and production processes control. The Smart
Factory model description is formulated in the context of an Enterprise Resource Planning
(ERP) organizational strategy [
The following types of agents were identified: • Central Agent - Central Computer; • Modules Agents: Resource Management Module Agent, Executor Management Module
Agent, and Operations Management Module Agent (Comp1, Comp2, Comp3 respectively); • executors.
There is also some abstract wireless communication channel in the system. Figure 1 demonstrates our proposed Smart Factory informational interaction model overview.
Central Agent is the Central Computer, which communicates with the External Environment (for example, with a customer), verifies the information received from the control modules, and sends this information to the DataBase. The DataBase stores information about orders received by the Smart Factory, the work of system agents and manufactured products. Management Modules agents determine the available system resources, resources required for the production, and perform task-distribution procedures. Executing agents have levels, for each level access parameter is defined, i.e. set of executing agents: = {(11 |1), (12 |1), . . . , (1 |), ( |)}, where is the agent’s access parameter: 0 ≤ ≤ 1, that distributes agents by access levels and determines the available functionality. The following parameters are defined for each agent-executor: • a set of functions: = {1, 2, . . . , }, which depends on the agent’s access level and parameter; • agent’s resource set: = {1, 2, . . . , }, where relates to the agent ∈ , and represents his level; • the remaining time of executor is , if ≈ 0, then the agent is redirected from the set of to the = { ∈ : ≈ 0}, and = ∖
Each = { , , }, where = 0 if the agent is busy, and 1 if the agent is free, and is the agent’s coordinates. The information space can be described as = ∪ ∪. . .∪, where is the information on Smart Factory’s functionality, is the Smart Factory’s rules, and is the information on Smart Factory’s consumers.
Central agent has global knowledge on the information space. The resource management module possesses information on the resources. The agent-executors management module has information on the agent’s location and their status. The operations control module has information on the diferent levels of executing agents’ functions, ways of transmitting information over the communication channel such as encryption, transmission protocols, etc. The combination of these modules constitutes a certain computer Shop.
The manufacturing production can be represented as = {1, 2, . . . , }, after converting each product into some function by the Central agent: = (, , , , ), this information is sent to the Shop, where, according to the provided function, resources, and Comp2
...
Product
Comp3 ...
Shop executor1a executor1b
executor1n abstrPr1a abstrPr1b
abstrPr1n ... ...
...
External Environment
Central Computer Comp1 the required time, tasks are distributed among the executors agents. The production process is divided into several tasks: = {1, 2, . . . , }, where = () and ∑︀ = , which means that all tasks are required to be performed to manufacture the product.
Further, at each executing agents level, a task is performed, for which the access level and functionality are defined. After that, the executing agents proceed to perform the assigned tasks, the results of which are: 1, 1, . . . , 1. Further information on abstract products (represented by (1)) is sent to the Shop, where it is verified for the correctness of their assigning to the executing agents. All verified abstract products are assembled at . After that, information on the product is sent to the Central Computer, where it is verified for compliance with the product requirements. If the verification procedure passed successfully, the information on the product is sent to the DataBase, and the product is sent to the customer.
= ( 1) ∪ ( 1) ∪ . . . ∪ ( ) (1)
For the centralized factory model, we introduce two smart contracts’ types. The former assure the relationship between the External Environment and the Smart Factory, the latter is used to organize the work inside the factory.
The response for product manufacturing comes from the External Environment. Then, the Central agent determines the required resources and functionality: = (, , , , ). If the manufacturing is possible, a smart contract is composed between the Factory and the External Environment: = (, , ), where is a producing time limit, which is determined by the External Environment, is a function that defines the resources and functionality, required to be performed by the factory: = ( , , , , ). However, there are several conditions for the contract generation process: • if → 0 : = ; • if ∈ < : = ; • ≥ .
Information on the established contract is sent to the DataBase: = {1, 2, 3, ...}, where = (). After the manufacturing response is transferred from the Central agent to the Shop, the Shop split the production procedure into certain tasks: = {1, 2, . . . , }, = (). For each task, the access level , resources amount and functionality are defined : ( ) = {, , }.
In the next step, the Shop forms internal smart contracts: = (, , , , ), where ⊂ is set of task executors agents, and , are functionality and resources amount of these agents. In addition, the following contracts’ conditions are introduced: • ≥ . • if ≥ (, , ) : = ; • → 0 : = ; • () ≤ , , ; If one of the contact’s conditions does not met, the contract is canceled.
When the contract is established, information on it is sent to the factory’s DataBase: = {1, 2, 3, . . .}, where is represented by (2). That is, knowledge on the contract is linked to the knowledge on the previous contract − 1. This blocks’ sequence forms a chain of related information. Information on the first contract 0 is defined as: 0 = (0).
= () × (− 1) (2)
In this paper, we proposed a novel approach for Smart Factory elements informational interaction using smart contracts. The model is based on a multi-agent approach and ERP organizational strategy, which divides the production process into several modules and is focused on continuous balancing and resources optimization. Two smart contract types are introduced: the former for generating a contract between the Smart Factory and the External Environment, and the latter for manufacturing organizing inside the Smart Factory. The smart contracts integration into the production process allows to automate decision-making and execution control, reduce the probability of manufacturing a low-quality product, and decrease production costs.As future plans, we intend to enhance the proposed Smart Factory elements’ informational interaction model and integrate other manufacturing organization means into it, as well as conduct an empirical study to assess the performance gain with smart contracts.