Development of Digital Radiographic Mobile X-ray System responding to requirements for safety, ease-of-use, and design for optimized performance in hospitals
This article introduces the story of the MobileDaRt Evolution MX8 developed from close communications across the globe with patients and medical practices.
Telescoping support column
"I know the concept of the device, but..."
"What about the supports?"
"If an X-ray tube support column cannot be expanded or retracted, it won't sell."
These remarks were made at a bi-yearly strategy meeting where Shimadzu marketing representatives from across the globe and R&D members from HQ gathered together. The R&D members of the Diagnostic X-ray Group in the Medical Systems Division felt awkward listening to these comments. At this meeting, the next generation of Shimadzu’s MobileDaRt, digital mobile X-ray system, was being discussed.
This system is designed to be moved around the hospital allowing X-ray’s to be taken anywhere in the hospital and is the single best-selling product that represents Shimadzu's global strategy. The MobileDaRt series has sold a total of 4000 units worldwide. It is sold all over the world and had the largest market share in the United States at one time.
That said, the previous MobileDaRt Evolution model has been out for seven years while competitors have also studied the MobileDaRt and have come close to copying it in terms of maneuverability. In addition, they have come to gain market share by incorporating measures to greatly improve usability. The biggest contrivance was "telescoping X-ray tube support column".
A “support column” is a column to which main components such as X-ray tubes are attached. The column of the mobile X-ray machine typically is stationary and has a height of about 180 centimeters. Competitors, however, have succeeded in making the support column collapsible, enabling the whole system to be compact when not taking x-rays.
"When a mobile X-ray system is moved throughout a hospital, the column obstructs the operator's view. In any hospital, not only the patients but doctors, nurses and support staff, are in a hurry to respond to emergencies, so if they bump into each other, it creates a big problem. If you think about it in this way, the telescoping support column was a very reasonable request.” (Shibata)
The demand for an expansion mechanism had been heard before now. However, if we try to create a mechanism that can both expand and contract freely while satisfying the durability and safety requirements of medical equipment, it leads to a drastic increase in cost and a loss of competitiveness. The R&D members at HQ proposed various alternatives, but the sales members, who know the medical environment best, did not agree.
There is one more key reason why they expected the development team to succeed. That's because MobileDaRt is an important "door opener" in building relationships with customers.
In the case of large-scale X-ray diagnostic equipment like Special Procedure labs and RF table systems, it is necessary to consider installation as part of the design of the facility. On the other hand, mobile units do not have the same restrictions on the location of installation. Furthermore, the price is lower than large scale X-ray systems, so it takes less time to negotiate a contract and if new customers are satisfied with the performance of the MobileDaRt, they may also be more interested in Shimazu's other products. That's why the sales force desperately wanted the R&D team to develop a telescoping support column that would allow customers to experience the power of the MobileDaRt in sales demonstrations.
"We must do this" said Toshiaki Nakamura of the Healthcare Business Strategy Unit in the Corporate Strategy Department and a development team leader for the proposed new MobileDaRt system. With a deep breath he looked around at the other members and saw that their eyes also agreed with this decision.
"Bring me the SHIMADZU."
In this way, it was decided that the next MobileDaRt would be equipped with a telescoping support column. Believing that development would take time, the team started developing the telescopic mechanism ahead of having a written specification for the next model.
"The telescopic column is central to the new model design, so if the development fails, the product itself will fail. Honestly, there was real pressure." recalls Hayakawa, who is in charge of mechanical engineering.
Spring and wire are key to the telescopic mechanism. Other companies used electric mechanisms, however, given the amount of battery capacity that can be loaded on a mobile unit, precious electricity should be used for radiography. All members of the team shared the view that "A latecomer cannot be inferior to others." and that thought encouraged Hayakawa to do his best.
Through trial and error, they came up with a mechanism that transmits the force of a spring while winding a wire in a spiral coil. The idea is to make the coil spiral so that it can absorb changes in the spring's repulsive force and move the column smoothly from start to finish.
The mechanism is simple, but each part requires an exquisite balance that cannot be easily achieved. With a math textbook in hand, he began to repeat simulations, prototypes and experiments. Before he knew it, his textbooks were covered with oil stains.
After a number of prototypes, he was able to gain some insight into the mechanical engineering of telescoping support column. A formal development approval followed and there was no turning back.
The following year, product designer Sugie joined the team. At that time, Sugie was also involved in a project to develop a unified concept for all of Shimadzu's medical imaging device designs. The new MobileDaRt had been declared the first X-ray machine to adopt this concept.
"The new concept is 'Bright'. We decided to use a simple design but use bright colors because we wanted both patients and medical technologists to feel cheerful. But what is bright white? It took many months to make the color adjustment and send our final color samples to the sales managers to review." (Sugie)
There were also additional design requests from our sales force. They wanted a bigger "SHIMADZU" logo on the side of the system. “This system is delivered to the hospital, and when it moves around, they want to promote the SHIMADZU name. In the future, we want our customers not to ask for a mobile but to say 'Bring me the SHIMADZU.' just as common as saying 'bring the mobile unit.' at hospitals. " (Shibata)
Power of communication
"The development should be in time for the North American exhibition in November." This was the deadline directed by the division general manager. However, the progress of the development started to delay. Takayanagi took over as the team leader from Nakamura who was concentrating on his own development work. Takayanagi became the center of the project, with the quality assurance department, the production department, and the service control department all involved, resulting in a close-knit product development team.
"It would have been difficult to catch up if development had continued as before. However, in order to develop what we viewed as our most important product, a collaborative project was promoted to share information across all departments of the Medical Systems Division. As a result, the relevant departments immediately shared information on any problems that occurred, and the decision-making and problem-solving became faster spread out across all development teams. I realized once again the importance of communication with a shared sense of purpose." (Takayanagi)
In November 2017, Shimadzu's latest mobile X-ray system, the "MobileDaRt Evolution MX8 Version" was released at the Radiological Society of North America (RSNA) as planned. The new model, which has a simple shape with less bumps and a new white and brighter colors, showed visitors its superior mobility and functionality. When they positioned the demonstration unit’s X-ray tube, it moved smoothly and could be operated with only one hand and with little force. Everyone who touched it commented on the ease of its maneuverability.
Nakahara, who has been involved in the development of the MobileDaRt series for a long time, attended the RSNA conference on behalf of the project engineers. "On the day before the exhibition, when the new product was unveiled at a kick-off meeting in front of sales and marketing members that gathered from all over the world, everyone celebrated the product launch with a standing ovation. I will never forget that excitement for the rest of my life." (Nakahara)
The close communication between sales, development, and the entire division resulted in the achievement of a single goal. The MobileDaRt Evolution MX8 Version won the Good Design Award in 2018 for significantly improving patient-engineer relationships.
Members involved in the development of the MobileDaRt Evolution MX8 Version. From the bottom right, clockwise: Masaaki Shibata, Assistant Manager of Global Marketing Department, Medical Systems Division; Tomoya Sugie, Assistant Manager of Product Design Unit, Corporate Product Design Center; Tsuyoshi Takayanagi, Manager of R&D Department, Medical Systems Division; Tadahiko Nakahara, Manager, and Toru Hayakawa, Assistant Manager of R&D Department, Medical Systems Division
Shimadzu MobileDaRt Evolution Digital Mobile X-Ray System MX8 Version with Superior Drivability and Functionality
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