Pinpointing exactly what may be going wrong inside a patient’s body has long been a challenge for the medical fraternity, but in the past few decades, advances in medical technology have allowed radiographers to non-invasively map and assess the inner workings of patients’ bones, digestive systems and blood vessels. These flouroscopes, angiograms and other radiographic applications can be achieved through a series of X-ray images that can then be stitched together or animated to create increasingly detailed imagery for medical analysis.
In addition to utilising advanced computer software to process the high-resolution radiography imaging, even the table upon which the patient is placed needs to be moved and controlled with smooth precision – often at a wide range of different angles and positions. Motion control specialists Parker Hannifin was on hand to help CAT Medical Systems develop the Helios DRF, a fully digital remote-controlled tilting table.
Italian firm CAT Medical Systems has been developing diagnostic X-ray systems since 1991, becoming part of the Assing Group in 2007. By adopting digital technology and enlarging its product portfolio, CAT has collaborated with a major Italian research institute to become a leader in highly customisable solutions according to each user’s specific requirements.
Reliable, precise movements
In their quest to build a radiographic tilting table that was light, compact and space-saving, CAT approached Parker Hannifin to source the servo drives and motors that would be the key components behind the Helios DRF’s movements. In a patient table such as this, the absolute precision and reliability of servo motors and drives is a non-negotiable requirement for the even movement and overall safety of patients.
For upper and lower gastrointestinal barium enhanced studies, the table needs to smoothly tilt the patient from a horizontal position right up to a vertical position. This movement allows the liquid to flow through the patient’s digestive system while being captured in real time by the fluoroscopic X-ray source.
Each movement of the Helios DRF has been engineered to facilitate optimal operator use, to ensure maximum patient safety and to prevent extraneous patient movement during the examination.
Low inertia, high performance
Each Helios DRF machine is equipped with six Parker SMB low-inertia brushless servo motors ranging from 82 to 115 Nm, with four of the motors equipped with a holding brake for additional safety.
The SMB series brushless servo motors combine cutting-edge technology with extremely high performance. Utilising innovative 'Salient Pole' technology, featuring Neodymium-Iron-Boron magnets uniquely encapsulated to the motor shaft, these synchronous servo motors can achieve very high accelerations and withstand high overloads without any risk of demagnetisation or detachment of the magnets.
In addition, six SLVD-N servo drives ranging from 5 to 10 A receive command signals from the controller, amplify the signals and transmit current to the servo motors to produce the precise range of motion, torque and positioning required.
The first servo motor controls the up-and down motion of the table for easy patient access, enabling the table to be lowered to a minimum of 43 cm from the ground, the lowest of its category. The second motor allows the table to move transversally up to 30 cm outwards. The third and fourth motors control the oblique projections of the X-ray source. The fifth servo motor controls the movement of the column holding the X-ray source, allowing it to extend up to 180 cm from the table surface. The sixth and final motor controls the tilting motion of the table, enabling a full 90° range of motion for fluoroscopy and other radiography applications.
A supportive partnership
With its excellent quality:price ratio and its strong footprint in the Russian market, where CAT Medical Systems have many customers, Parker was an obvious choice as a supplier of servo motors and drives for the Helios DRF, but it was the engineering support they received that made it a truly rewarding collaboration.
“Parker has supported the customer along all the development phases, from the engineering stage to the set-up of the first machines,” said Michelangelo Matullo, Automation Account Manager Central South Italy at Parker Hannifin Italy. “An important parameter for the customer has been the reliability and movement repeatability of Parker products in comparison to previous solutions.”
“We have chosen Parker because of their reputation, quality and reliability of their products,” said Ing. Alessandro Biasini, R&D Project leader at CAT Medical Systems. “Furthermore, thanks to Parker’s innovative technologies, it has been possible to constantly improve the performance of our machines. Partnering with Parker is profitable, for both the technical and commercial support.”
