DOMO (Dynamic Offsite MX Operator)

An automated system for mounting and dismounting pre-frozen crystals has been implemented at the SIBYLS beamline. DOMO is based on the Stanford Automounting System (SAM) developed at the SSRL which was designed around the EPSON SCARA robotic arm.

Sample Cassettes

The pre-frozen crystals are mounted on standard Hampton Research 18mm CrystalCap Copper Magnetic pins and held within a compact cylindrical cassette, each holding up to 96 crystals.

DOMO Sample Dewar

A dispensing dewar holds two cassettes under liquid nitrogen on a platform adjacent to the goniometer.

DOMO magnetic tool and gripper/cryo tongs

DOMO uses a small magnetic tool to extract samples from, and insert samples into a cassette, and a cryo-tong tool to transfer them to and from the goniometer.

in action:

DOMO Operation

DOMO is controlled via the Blu-Ice GUI.

Guidlines for freezing crystals

In general ice is your enemy. Use fresh liquid nitrogen. Freeze crystals in small batches. The SMB group at SSRL has extensively documented best practices for preparing samples and loading them into the cassettes so I will refer you to their instructions.

Request a cassette kit

This is the foam dewar and assorted tools that come with a cassette loading kit.

You can purchase these from Crystal Positioning Systems or if you just want to try it out first I can probably lend you a kit. Please call (510.495.2697) or email me sclassen@lbl.gov for requests.