RPDS AI ยท USER GUIDE
Technical Documentation
Understand the concepts, prepare your data, and follow a clear path from process measurements to useful insights.
THE ESSENTIALS
Getting started
Begin with a specific process question. Decide what you want to estimate, compare, or improve before choosing a workflow.
Prepare your data
Explore measurements and resolve data quality issues.
Open Data CleaningEstimate a variable
Build a model using the process inputs you can measure.
Open Soft SensorCompare your batches
Establish a reference and investigate process deviations.
Open Golden BatchDefine the target variable, its unit, and the outcome that would make the analysis useful. For example: estimate final product concentration from temperature, pH, and feed rate.
BEFORE YOU BUILD
Data preparation
Reliable analysis starts with consistent measurements. Check the dataset before selecting features or training a model.
- Confirm the structure. Use meaningful column names and consistent units. For batch analysis, clearly define batch identifiers and the time or progress axis.
- Review data quality. Inspect missing values, duplicate records, and unusual readings. Investigate outliers before deciding whether to remove them.
- Select the target and inputs. Choose the output to estimate and the measurements available at the time a prediction will be made.
- Keep evaluation data separate. Avoid using information from the test set during preprocessing or feature selection. For time-dependent data, preserve the time order.
An input recorded only after a batch finishes cannot support a prediction made during that batch. Choose inputs that match the intended prediction point.
PROCESS REPRESENTATION
Digital twin
A digital twin is a virtual representation of a physical system or process. It can combine measured data, mathematical models, and machine learning to describe process behaviour.
When to use it
Use process models to study relationships between operating conditions and outcomes, or to explore scenarios before making a plant change.
What it helps you understand
- How process inputs affect performance.
- How operating scenarios compare.
- Where observed behaviour differs from the model.
A reactor model can estimate how temperature and feed conditions influence reaction performance. Compare its predictions with measured results before using it to guide decisions.
The RPDS model workflow provides tools for exploring data and developing predictive models. A live digital twin also requires appropriate plant data integration and validation.
Explore the model workflowFUTURE OUTCOMES
Forecasting
Forecasting uses historical observations to estimate future values. The forecast horizon defines how far ahead the prediction is intended to apply.
Common applications
- Estimate future production or demand.
- Anticipate energy consumption.
- Predict process yield or batch duration.
Recommended approach
Define the prediction horizon, preserve the sequence of observations, and evaluate predictions against later periods that were excluded from training.
Use historical operating conditions to estimate the yield of a future production cycle. Compare predictions with a simple baseline to establish whether the model adds value.
Estimating a value from current inputs and forecasting a future value are different tasks. Time-based forecasts require an appropriate time structure and evaluation strategy.
REFERENCE & COMPARISON
Golden batch
A golden batch is a reference production run, or a set of runs, selected for desirable quality and process performance. Its profile provides a benchmark for comparing other batches.
Follow the workflow
- Upload and inspect. Review the batch data and choose the target variable.
- Define the reference. Select and lock the golden batches using your process and quality criteria.
- Review statistics. Examine reference profiles, variability, and relevant process variables.
- Compare and investigate. Review similarity and deviations, then use process context to interpret the differences.
For a fermentation process, compare temperature, pH, and feed profiles against successful reference batches. Investigate where a lower-yield batch departs from the reference.
A close match to a reference profile does not by itself establish product quality. Interpret comparisons alongside measured outcomes and operating conditions.
Open Golden BatchINFERENTIAL MEASUREMENT
Soft sensors
A soft sensor is a computational model that estimates a process variable from other available measurements. It is useful when the target is difficult to measure continuously or requires laboratory analysis.
Choose the inputs
Select measurements related to the target, such as temperature, pressure, pH, or flow rate. Ensure they are available when you intend to make a prediction.
Validate the estimates
Compare predictions with measured target values on held-out data. Review the error across operating conditions, rather than relying on a single overall score.
Estimate biomass concentration from pH, dissolved oxygen, and temperature. Laboratory measurements provide the reference values for training and evaluating the model.
Review model performance when feedstocks, equipment, or operating ranges change. Predictions outside the training range may be less reliable.
INTERPRETING RESULTS
Reading your graphs
Choose a graph that matches your question. Always check the variable names, units, and data range before interpreting a pattern.
| Graph | Use it to examine | What to look for |
|---|---|---|
| Histogram | The distribution of one numerical variable. | Spread, skewness, multiple peaks, and unusual values. Bin size can change the apparent shape. |
| Time-series plot | How a variable changes over time or batch progress. | Trends, shifts, cycles, and differences in timing. Compare batches on a consistent time basis. |
| Scatter plot | The relationship between two numerical variables. | Patterns, clusters, and outliers. A relationship does not establish cause and effect. |
| Correlation heatmap | Pairwise relationships among numerical variables. | Strong associations and redundant inputs. Correlation may miss nonlinear relationships. |
| Predicted vs. actual | Agreement between model estimates and measured values. | Distance from the agreement line, systematic bias, and errors at high or low target values. |
Using a histogram
- Choose a numerical variable, such as temperature or yield, and confirm its unit.
- Review the frequency of observations in each interval, or bin.
- Compare the distribution across relevant batches or operating conditions.
- Investigate unusual values using the original records and process context.
Ready to work with your process data?
Explore RPDS workflows