Physical quantities provide information Up until now, such test series required a great deal of manual work. The various steps could only be partially automated. With CYRIS® FLOX, has cre- ated a fully automatic device that can perform the multi-day test run without human intervention and can also fully document the results. At the heart of the test setup is a micro- titre plate made of transparent material that has 24 wells, or test chambers. These hold the cell samples like miniature Petri dishes. 24 pipettes on a robot arm supply the small cultures with nutrient solution and feed in the substances that are to be tested. In doing so, a different composi- tion of the solution can be selected for each pipette. Each test chamber is equip- ped with sensors for oxygen content, pH value and electrical resistance. The indi- vidual test chambers are photographed from below at regular intervals through a microscope lens. Development for automation is a start-up with acade- mic roots. The founders of the com- pany worked previously in university research. There, they used motors from other manufacturers for the initial pro- totypes of their device. These did not prove to be suitable and were later replaced by models from FAULHABER. They convinced with their compact design and the reliability of the com- ponents. When it came to the further development of the system to prepare for series production, there was, thus, no need to find a drive supplier. New goals were, however, defined for this area: "We wanted to work with as few different motor types as possible,” says Matthias Moll, head of development, describing the initial situation. "We also wanted a simpler arrangement for the wiring. We were looking for a drive in which the electronics are already inte- grated. Up until then, they were housed in a control element of the robot arm, which meant that many cable connec- tions were necessary in a moving ele- ment.” In addition, the motors should be able to report errors, for example, if overheating causes or threatens to cau- se a mechanical blockage. In combination with an integrated Motion Controller of the CxD series, the 2232…BX4 brushless servomotor satisfi- es these new requirements of the tech- – as well as all nicians from others, such as high performance in an extremely compact design, low weight and volume as well as compatibility for laboratory use. Six motors are built into the CYRIS® FLOX analysis device. Three of these move the pipetting head in the robot arm on three axes. They are responsible for moving the pipettes precisely over the microtitre test cham- bers and for moving into position just above the chambers for discharging the solution. A fourth motor drives 24 suc- tion pistons, which transport up to 200 µl of culture medium in sterile pipette tips. Two motors move the microscope on an XY table below the cell samples. The photos of the individual test cham- bers are taken from below through the transparent material of the microtitre plates. Precision and reliability in continuous operation "In order to track the development of individual cells in the time lapse later on, the lens must always be at the exact same point under the test chamber,” says Matthias Moll as he explains the challenge in this step. "With the help of the FAULHABER motors, we can precisely position the table to within two microme- tres.” For comparison: A human hair has a thickness of between 50 and 70 microme- tres. The motor that drives the pistons of the pipette head must also operate very precisely. Only if the quantity of liquid corresponds exactly to the specifications can valid test results be produced. In CYRIS® FLOX systems, precision is a con- tinuous task. The maxim for the motor applications is, therefore, repeatability. The exact movement must be performed repeatedly for the days of the test in short intervals without deviation. "We expect the highest possible level of reliability 12 12 0 1 . 2 0 2 1 M E D I C A L & L A B O R A T O R Y E Q U I P M E N T