Low friction belt treadmill for use in space constrained experimental rigs
Designed at HHMI's Janelia research campus by the jET team, this treadmill is relatively small and inexpensive compared to most existing designs. It is manually driven with an encoder which tracks the movement of the belt. The encoder does not have to be connected, unless it is desired to record or analyze the motion. Encoder interfaces are documented in a separate repository and on Flintbox.
It may be used for natural action (e.g., walking) for the mouse to take during an experiment instead of standing still. For example, some users let the mice walk normally on the treadmill and then play a tone the mouse associates with a trained response to see if the mouse will start or stop moving.
Advantages: This was designed to fit underneath MIMMS 2P microscopes where space is limited. There are now some commercial options available based on this design, as well as other commercial options.
Interface: These may be placed under an imaging microscope or other behavioral setup with a head-fixed rodent on it.
Construction: The treadmill is composed of 3D printed parts and two machined axles that can be made by a machine shop on a lathe with simple tooling. There are also some laser cut side walls on the treadmill and a laser cut belt as well. The belt is seamed together using a heat sealer such as this one from Amazon: 8" (200mm) Impulse Manual Bag Sealer Heat Sealer http://a.co/8Zj5Gaq
Teflon tape used to hold the belt halves in position: http://catalog.cshyde.com/keyword/s-ptfe-teflon-products-ptfe-teflon-tapes-4/skived-high-density-ptfe-tape-with-silicone?key=all&&keyword=R233&SchType=2
See the individual part drawings for more detail on printing and fabricating each parts. See the attached assembly drawing for the BOM including purchased commercial items needed to complete the treadmill.
Operation: Researchers can physically mount the treadmill and place the mouse on top of it. Some training is required of the mouse.
Maintenance: The belts need to be cleaned regularly to keep them turning smoothly. Many users have spare belts that they swap between. If there is enough space in your rig other options such as the cylindrical treadmill are good options that do not require as much maintenance.
Opportunity: Free to make for Non-Profit Research by downloading the design here or on Flintbox. See included hardware license.
Rights and designs available for Commercial License. Janelia makes no endorsements or guarantees of licensee products.
For inquiries, please contact innovation@janelia.hhmi.org and reference: Janelia 2017-049 https://hhmi.flintbox.com/technologies/5e4af2a5-6154-4bc0-a10d-56b5b6dce978
To cite the designs, please use DOI: https://doi.org/10.25378/janelia.24691311