The Lab’s Best Friend: 3D Printed Dog Treat Dispenser Outperforms Its Predecessors | Nebraska today

Welcome to Pocket Science: an overview of recent research by Husker scientists and engineers. For those who want to quickly learn the “What”, “So what” and “Now what” of Husker research.
What?
A good deal of dog research, including some conducted at the Nebraska Canine Cognition and Human Interaction Lab, involves automatically dispensing treats that reinforce behaviors and help test a dog’s ability to learn.
Reliably dispensing a specific number of treats can be vital, especially when the number of treats assigned depends on – and is intended to gauge – a dog’s ability to discriminate between numbers or quantities. In these cases, handing out too many or too few treats can ruin the validity of a study.
Even so, treat vending machines typically only dispense the correct number 70-80% of the time. Meanwhile, having a person hand out the treats may introduce undesirable effects and limit experimental designs.
So what?
Walker Arce and Jeffrey Stevens from Nebraska recently designed a 3D printable dispenser that holds up to 59 treats and can be built for less than $200. After building five of the dispensers and testing each 100 times, the duo found that their design automatically dispensed the correct number of treats 96% of the time.
Because it includes a Raspberry Pi – a miniature computer weighing less than 2 ounces – the dispenser can also be paired with a monitor, mouse and/or keyboard.
Now what?
After releasing the 3D print files, assembly guide, and open-source software for the design, Arce and Stevens said labs can customize the system based on their own research questions.
Arce and Stevens illustrated a single potential application by mounting a touchscreen on the dispenser and training a dog to sniff the screen. The Raspberry Pi presented a choice between two collections of dots on the screen, recording the option selected by the dog. The pre-programmed system then dispensed the number of treats corresponding to the dog’s decision.
Hardware adjustments could also allow studies involving birds, rats and other species.