Setting up ELS with BRFplus

Business Rules Framework plus (BRFplus) provides a comprehensive application programming interface (API) and user interface (UI) for defining and processing business rules. It allows you to model rules in an intuitive way and also allows you to reuse these rules in different applications.

Applications use BRFplus in the following scenarios:

• Validation of data and detection of invalid data and states

• Matching responsibilities, suitable products and locations

• Calculation of costs, overhead and risks

• BRFplus as a technical configuration engine

BRFplus components include application, function, catalog, expression, action, data object. The rule interface is called a function. Rules are implemented in the application as expressions. The three modes of operation available in BRFplus to process the function are:

• Functional mode
• Event mode
• Functional and Event mode

The rule input is known as a context and the rule output is called a result. Context and result consist of elements, structures and tables. BRFplus supports features including:

• simulation
• trace
• transport
• XML export and import

Using labor activities instead of external process steps and work step sequences for the normal time determination has several advantages. For example, the external process step for all picking tasks is PICK. In contrast, you can define different labor activities to distinguish between picking in different activity areas or between case picking and pallet picking.

With labor activities you can structure the planned and executed workloads without changing the external processes steps that may already exist, and you can (together with evaluation types and labor activity groups) monitor planning and execution. You can also use them for reporting purposes.

To use labor activities, you must define a labor activity catalog, which is a list containing all the labor activities you can use in your warehouses. To use labor activities from the catalog, you must activate the labor activities at warehouse level. Evaluation types are used to classify the working time of labor activities. Evaluation types are mandatory and they must be defined before you define labor activities. Labor activity groups are optional and are used for reporting purposes.

Labor activities can be determined in two ways:

• Directly:

  This is used if there is a 1:1 relationship between a labor activity and an external process step. This is always used for indirect labor, for example, changing a battery.

• Using a decision service in BRFplus:

  If there is no 1:1 relationship between a labor activity and an external process step, for example, in the case of picking or staging, a decision service in BRFplus determines the labor activity at runtime. It does this by considering context-dependent information such as external process step, activity area, material group, location, or reference document data (such as a warehouse order).

The BRFplus decision services define the interfaces between EWM and BRFplus and enable data exchange between EWM and BRFplus at runtime using:

• Context (parameter) to pass data from EWM to BRFplus.

• Result (parameter) to return the result of a decision from BRFplus to EWM.

EWM provides several decision services (functions) in the BRFplus system application Labor Activity Service (/SCWM/LM_LA_SYS). You can replace the predefined decision services for the labor activity determination with your own decision services, without implementing a Business Add-In (BAdI). You need to assign your own decision service to the decision service context in Customizing for Extended Warehouse Management, under Labor Management → Assign BRFplus App. and Function to Decision Service Context.

Additionally, there are several BAdIs available for creating enhancements for each context, for example, if you want the labor activity determination in BRFplus to consider additional information.

In most cases, you need to define your own business rulesets, business rules, and expressions for each decision service provided by EWM. You also need to register your own business rulesets to the decision services provided by EWM in the BRFplus workbench at design time. A business ruleset contains a set of business rules. A business rule is defined again by a set of expressions, such as decision table, decision tree, case expression, and Boolean expression. You can use the Customizing application Labor Activity Service Contents (/SCWM/LM_LA_CUST) provided by EWM as an example for your own business rule definitions. You can use the example application /SCWM/LM_LA_CUST if it is suitable for your warehouse processes. To do so, you must first add and activate its contents to the corresponding decision tables in the BRFplus workbench.

EWM provides several predefined, default decision services for calculating the planned duration (normal time) of planned workloads and for the adjusted planned duration (normal time) of executed workloads. These are all part of the application /SCWM/LM_ELS_SYS. You can replace the default decision services for the time calculations with your own decision services. You need to assign these to the specific context in Customizing for Extended Warehouse Management, under Labor Management → Assign BRFplus App. and Function to Decision Service Context.

You can make your own enhancements for each context, for example, if you want the time calculation in BRFplus to consider additional information. For this purpose, each decision service call is encapsulated by a Business Add-In (BAdI). Each BAdI provides a fallback implementation which calls either the standard decision service or the decision service you specify in Customizing. For more information, see the Enhancement Spot for ELS Determination (/SCWM/ES_LM_ELS).

You want to calculate the normal time for an executed workload of a warehouse order. This is a pick warehouse order containing three warehouse tasks, each with different products and different units of measure.

When the warehouse order is created, one planned workload is created for which the labor activity is determined and the travel time is calculated. The results are provided as input for the normal time calculation. The decision service ELS for Warehouse Task is called separately for each warehouse task of the warehouse order. The results from each calculation per warehouse task are summarized and passed on as an input value to the decision service ELS for Warehouse Order for Warehouse Task. This decision service is called at the end to calculate the overall normal time of the planned workload for the warehouse order.

This example uses the following, simplified data for the warehouse order, labor activity, and travel time:

This example uses the following, simplified data for the warehouse tasks:

The decision service ELS for Warehouse Task is called for each of the warehouse tasks. The labor activity is provided as the input and it determines how the normal time is calculated. For example, the labor activity code SCRAP might have a fixed time of 100 seconds per warehouse task, but here we have the labor activity code OPICK. OPICK does not have a fixed time. Instead, it requires a second step to calculate the normal time.

The following table is a simplified representation of the normal time calculation per unit of measure:

Given the above data, the normal time per warehouse task is calculated as follows:

• Warehouse Task 1: (10 PC * 5s) + 10s = 60s

• Warehouse Task 2: (5 CAR * 10s) + 20s = 70s

• Warehouse Task 3: (1 PAL * 5min) + 40s = 5min 40s

The normal times of all the warehouse tasks in this warehouse order are added together to give 7min 50s (= 60s + 70s + 5min 40s). The result is passed on to the decision service ELS for Warehouse Order for Warehouse Task.

The normal time per warehouse task contains the time required for each pick. We also need to add the times for the movements between the picking locations. For this, we need the travel time, which is provided as the input to the decision service. We also add a fixed offset of 4 minutes to the overall normal time to account for the time a worker requires to read the information about the warehouse tasks.

Using this information, the rules of the decision service ELS for Warehouse Order for Warehouse Task calculate the sum of the pick duration per warehouse task, the travel time between the individual pick locations, and the fixed offset for reading the information. The overall normal time for the warehouse order, thus the executed workload, is calculated as follows: Normal Time: (Sum of Warehouse Tasks) + (Travel Time) + (Time for Reading Information).

In this example, this would result in the following normal time: (7min 50s) + (4min 27s) + (4min) = 16m 17s.

You can display traces from BRFplus for the labor activity determination, travel distance calculation, engineered labor standards, and PFD factor.

To activate the traces, select Extended Warehouse Management → Settings → Application Log → Activate Trace in BRFplus. For each trace object, you can activate either a simple context trace or a lean trace.

• The simple context trace shows only the input data of a BRFplus call and the result.

• The lean trace additionally shows how the result was calculated.

You can use authority checks in BRFplus to ensure that only specified users are able to edit certain rules in BRFplus. For example, so that a warehouse supervisor can only make changes to rules for his or her own warehouse.

For this purpose, BRFplus provides authority checks for editing rules, based on BRFplus functions. The idea is to call different BRFplus functions for the different warehouses. Users only have maintenance rights to the functions for the warehouses for which they are responsible. The same functions can be called for a group of warehouses. Therefore, a user can maintain rules for a group of warehouses as long as they have the required authority for the corresponding functions.

To define which function is called for which warehouse, maintain the following settings:

1. Use the BRFplus copy functionality to copy the BRFplus standard functions into a new application.

2. Enter the application and the functions for the warehouse in Customizing for Extended Warehouse Management, under Labor Management → Assign BRFplus Application and Function to Decision Service Context.

3. In BRFplus, provide the users who will be allowed to maintain rules for the warehouse with the authority for the corresponding functions.

If you want to use PFD when calculating the adjusted planned duration (or standard time), you can use the predefined BRFplus application /SCWM/LM_PFD_SYS or define your own application.

As import parameters, the BRFplus function context contains data from the following sources:

• Executed workload (EWL)

• Processor attributes, such as ID, service start date, processor type

• Shift, if an assignment between processor and shift exists

• Exception codes entered at time of execution

The result elements in the context are the PFD factor and the PFD allowance.

The system uses the BAdI Decision Service for PFD Calculation (/SCWM/EX_LM_PFD_DSM) to calculate the PFD factor and the PFD allowance. For more information, see Customizing for Extended Warehouse Management under Business Add-Ins (BAdIs) for Extended Warehouse Management → Labor Management → Personal Needs, Fatigue, and Unavoidable Delays → BAdI: Decision Service for PFD Calculation.

• With labor activities you can structure the planned and executed workloads without changing the external processes steps that may already exist, and you can (together with evaluation types and labor activity groups) monitor planning and execution. You can also use them for reporting purposes. To use labor activities, you must define a labor activity catalog, which is a list containing all the labor activities you can use in your warehouses. To use labor activities from the catalog, you must activate the labor activities at warehouse level. Evaluation types are used to classify the working time of labor activities. Evaluation types are mandatory and they must be defined before you define labor activities. Labor activity groups are optional and are used for reporting purposes.
• The BRFplus decision services define the interfaces and enable data exchange between EWM and BRFplus at runtime. In most cases, you need to define your own business rulesets, business rules, and expressions for each decision service provided by EWM.
• You can use ELS in BRFplus to calculate the planned duration (normal time) of a planned workload and the adjusted planned duration (normal time) of an executed workload. You can use the results of the labor activity determination and the travel distance calculation as the input for the ELS.
• In order to use BRFplus in Labor Management, you have to activate the usage for the warehouse number. When you have made this selection, ELS with work step sequences is not used anymore. You can display traces from BRFplus for the labor activity determination, travel distance calculation, engineered labor standards, and PFD factor. You can use authority checks in BRFplus to ensure that only specified users are able to edit certain rules in BRFplus.
• You can take personal needs, fatigue, and unavoidable delays (PFD) into account when calculating the standard time. The system changes the adjusted planned duration (also known as the standard time) with the PFD calculation. You either apply a PFD factor to the adjusted planned duration to compensate for time lost due to PFD, or you can add the PFD allowance to the adjusted planned duration.