Jfrog Pipelines support automatic triggers through webhooks, REST API based triggers, as well as manual triggers through the UI.
Jfrog Pipelines also provides you the ability to schedule a Pipeline to be triggered at specific date/times, or at a recurring interval.

You can use the cronTrigger resource of JFrog Pipelines to achieve the functionality scheduled triggers in your workflow.

Before starting I would like to quickly tell you about JFrog Pipelines key concepts which would help you understand this better.

CronTrigger Resource

cronTrigger resource provides cron-like functionality. It is used to trigger a build in a cron-like manner.
You can define the resource in your yaml config file as:

- name: cron                 #friendly name to remember
  type: CronTrigger
  configuration: 
    interval: "*/2 * * * *"  #follows the standard Cron format

This resource can be used as an inputResource to a step in pipeline as follows:

steps:          
      - name: bash_1
        type: Bash
        configuration:
          inputResources:
            - name: github
            - name: cron        #created CronTrigger resource name
        execution:
          onExecute:
            - echo "executing bash step."

If the CronTrigger typed resource is given as Input to a step then it gets triggered at the recurring interval or at a specific date as depends on what you configure in interval.
A new run will be created every time the step is triggered.
In my example, this bash_1 step will be triggered by cron resource in every 2 minutes as shown in the below screenshot:

You can also schedule to trigger this on a particular day by just updating the interval in the resource definition as per cron syntax.

Hope this helps. :)