Is there a way to Splunk two dimensional motion data in a defined space without individual GPS sensors?

I am looking to Splunk two dimensional motion data in a defined space without individual GPS sensors and display the data graphically. Anyone done this before and have any best practices, recommendations, and ideas on good portable sensors that could work with Splunk for this? Maximum objects tracked would be around 21, minimum around 14. Area would cover no more than probably 500 sq meters.