Workflow Description

Note

This description assumes the reader has a foundation in Bonsai that is built on the Trigger Workflow Description. Start there if you have not already.

Commutator GroupWorkflow

• The Quarternion node connects to the Commutator node. The Commutator node represents a GroupWorkflow operator named Commutator. A GroupWorkflow operator encapsulates a workflow fragment inside a single node. To inspect the encapsulated workflow fragment, double left-click the Commutator node.

• A node’s border represents the scope of the corresponding operator. For instance, the dashed grey line around the Commutator node indicates it shares a scope with the “main” workflow. In contrast, a solid line would indicates it defines its own scope. For more information, refer to the Bonsai documentation on this subject.

Note

To learn more about a respective node, refer to the desciption in the Properties pane that appears after left-clicking the respective node. If the node has a name that is different from the name of the operator it represents, the operator name is presented in parenthesis after the node name.

Sample Quarternion Data

• The Source1 node represents a WorkflowInput operator. A WorkflowInput operator is a source operator that emits items passed to the GroupWorkflow from the parent workflow. In this case, Source1 emits quarternion data that is what is passed to the input of Commutator.

• The Source1 and Timer nodes connect to the Sample node. The Sample node emits the most recent upstream data at an interval specified by setting the Period value that appears in the Properties pane after left-clicking the Timer node (in this case, 100ms).

Generate Automated Commutator Command

• The Sample node connects to the Heading node. The Heading node represents a PythonTransform operator named Heading. A PythonTransform operator contains a Python script for transforming items in an observable sequence. The script contained in Heading transforms quarternion data to a single quantity that represents direction the UCLA Miniscope v4 is heading. To inspect the script that performs this computation, double left-click the Heading node.

• The Heading node connects to Zip and Skip nodes. The Skip node also connects to the the Zip node. The Skip operator skips a number of items in the observable sequence or upstream data as specified by the Count value that appears in the Properties pane after left-clicking the Skip node (in this case, 1). The Zip operator emits a combination of two inputs. In this case, the Zip operator emits the most recently sampled heading data and the sample before that. In other words, if the Heading emits the \(nth\) item in an observable sequence, Zip emits items \((n, n-1)\).

• The Zip node connects to the AutomatedCommutatorCommand node. The AutomatedCommutatorCommand node represents a PythonTransform operator named AutomatedCommutatorCommand. The script contained in AutomatedCommutatorCommand transforms current and previous heading data to a commutator command. To inspect the script that performs this computation, double left-click the AutomatedCommutatorCommand node.

Generate Manual Commutator Command

• The KeyDown node represents a KeyDown operator. A KeyDown operator emits an item anytime a key/key combination specified by the Filter value that appears after left-clicking the KeyDown node (in this case, Alt+Right and Alt+Left) is pressed.

• The KeyDown nodes each connect to the String node.

• The String node represents a String operator. A String operator emits a string specified by the Value value that appears after left-clicking the String node (in this case, "{turn : 0.1}" and "{turn : -0.1}") anytime it receives an item from upstream item.

Send Commutator Command Over Serial

• The two String nodes and AutomatedCommutatorCommand each connect to the Merge node. The Merge node represents a Merge operator A Merge operator merges multiple observable sequences into one.

• The Merge node connects to a SerialWriteLine node. The SerialWriteLine node represents a SerialWriteLine operator. A SerialWriteLine operator writes serial messages appended with specified by the NewLine value that appears afer left-clicking the SerialWriteLine node.

Note

Because SerialWriteLine operator is a sink operator, it doesn’t transform data. In other words, its output is equivalent its input, and the SerialWriteLine operator passes that data to the WorkflowOutput as-is to the downstream operator.

• The SerialWriteLine node connects to a WorkOutput node. The WorkOutput node represents a WorkOutput operator. Items passed to the WorkOutput operator are emitted by the corresponding group workflow’s node (in our case, Commutator in the main workflow). This can be seen by double-clicking the Commutator node while the workflow is running.