Abstract
A mobile robot was installed in the Wellmont-Bristol Regional Medical Center Laboratory (Bristol TN) for lab wide specimen delivery in March of 1997, following Lab Automation 97 in San Diego, California. Significant staff reductions and other reorganization efforts in prior years (1–3) made daily survival difficult for the clinical support staff as well as technical employees. The Robocart offered an immediate and inexpensive platform to deliver specimens to work centers without requiring additional man-hours. This article will describe the eighteen month evolutionary process the WBRMC laboratory experienced using a mobile robot in an effort to automate our laboratory in a slow, progressive, and inexpensive fashion.
The California Computer Research Inc. ROBOCART (www.robocart.com), is a user programmable, tape following robot that is able to travel through almost any isle in our laboratory. The initial focus of “Rosie”, our robot, was to deliver specimens to work sites throughout the lab (Figure 1). The small profile of the robot offers almost total freedom in route development. Multiple stops were programmed throughout the lab, with six routes designed for high volume use. Rosie makes between 30 and 50 trips during the day shift.
The initial focus of “Rosie” was to deliver specimens to work sites throughout the lab.
The $ 25,000 system cost was readily justified using a business plan based on a $ 0.03 per minute capital/operational cost compared to the WBRMC $ 0.28 per minute cost for the average benefited employee (4). After seeing “Rosie” in action, an independent consultant working on a Prernier/BD Vacutainer System national review stated “… the cost is significantly less than the cost of actual employees. Also, the cart does not take vacations or call in sick. The use of the Robocart is unique in this size facility, and can be considered ‘best practice’(5)”. With a capital payback realized in less than nine months, Rosie was a huge success, with the staff as well as administration.
Special features of the Robocart include a sonar sensor for collision avoidance, opportunistic battery charging, 12vdc stepping motors designed to turn the robot on a central axis allowing for unlimited maneuverability, and the ability to send RF signals to any device. Even though the unit can transport 35 pounds, our average payload is less than five pounds. The internal Pentium Laptop PC using simple visual basic commands (6) controls the system movement. The robot employs X-10 wireless technology to control different devices by utilizing inexpensive, off the shelf, Radio Shack technology. The cart 1) rings a doorbell outside of Histology to alert the staff specimens are available for processing and 2) signals a robotic arm to unload specimen racks. The average transit time for a single run is less than two minutes.
Our second stage of automation began in March of 1998, following Lab Automation 98 in San Diego. At that time “Rosie” was modified with a “Pick N Place” (PnP) feature developed by Dr. Robin Felder and Staff at MARC (Charlottesville, VA). This unit (http://labautomation.org/marc/projects2.html) allows the Robocart to transport and “drop” specimens at specific work centers without operator intervention. Three high volume testing sites in “Chematology” (combined chemistry and hematology activities) and one in Blood Bank were chosen to receive the “Pick N Place” stations. The “Pick N Place” simple design has no moving or mechanical parts and uses magnets to transfer specimen containers to and from the cart and workbench. The average transit time after adding the PnP stations is about three minutes.
Adding the PnP stations resulted in increased cart utilization of more than 40% (Figure 2). Additionally, there was a significant increase in the number of specimens returned to specimen processing for archiving. This further reduced lost time and improved productivity. Sixteen other, non PnP, stations continue to be used with less frequency, and any number of new stations can be added through minor software modifications. If desired we can relocate PnP stations with minimal cost and organizational problems, a feature unavailable using fixed transport systems.
Adding the PnP stations resulted in increased cart utilization of more than 40%.
The third (evolving) phase of our automation adventure is similar to that described by Dr. Masahide Sasaki et al (7,8) whereby human scale robotic arms are used to transfer specimens (racks) to clinical instruments. As our first step, rather than using more expensive and inflexible conveyor systems to transport specimens to instruments, we are utilizing “Rosie”, the CCRI Robocart and a CRS Robotics (Burlington Ont.) human scale robotic arm (www.crsrobotics.com) to automate an immuno-chemistry system. Organon Technica (Durham NC) is marketing this platform for their MDA Coagulation system.
Based on preliminary work performed by Dr. Felder and MARC (8), Don Nagy of CCRI made simple program modifications that allow “Rosie” to transport racked bar coded specimens directly from specimen processing to an Abbott AxSYM. Once the Robocart arrives at the AxSYM, “Rosie” transmits a radio signal to a NEC 266 MHz PC, connected to the CRS robotic arm, and the ABBOTT AxSYM employing standard RS232 interfaces. The robotic arm moves the rack from “Rosie” to a platform next to the AxSYM. With specimen racks now removed the Robocart is released by a RF signal from_the PC and returns “home”. The robotic arm moves the rack of specimens from the platform to the AxSYM for testing (Figures 3, 4 and 5).
The project began in July(1998) and is nearly 80% complete. During the past three months project time dedicated to the development of this work cell has amounted to less than three weeks. This includes research, programming, and hardware development by CCRI. The project status can be seen by going to www.robocart.com and viewing the “top stories” section. A major goal of this project is to develop and utilize such an automated platform throughout the laboratory. Over 18% of our laboratory testing will be so automated when the Asxym project is complete.
This same automation platform will be used to automate our Beckman Coulter GEN S and STK S. Analogous to the mechanism used at the AxSYM workcell, racks with bar coded specimens will be manually loaded onto “Rosie” in specimen processing and transported to the workstation in Chematology. The arm will remove the rack and load the GEN S system for testing. Specimens that require manual testing (i.e. sed-rates) will be unloaded from the cart but placed in a specified location. Once the manual procedure is finished the rack will be manually loaded on the GEN S if appropriate.
The last development phase will focus on integrating this robotic concept with our two existing Beckman Coulter CX7 chemistry analyzers using a two axis robotic rack loader. The work cell will actually include the specimen processing area where specimens will be processed in Beckman sector centrifuges (up to 24 specimens at a time). Post centrifugation four racks, each with eight specimens, will be manually loaded on “Rosie”. The subsequent robotic process will be synonymous to that employed with the AxSYM and GEN.
When fully functional three major testing platforms will have been completely automated at marginal cost and providing maximum flexibility. The Robocart will be loaded with racked bar-coded specimens in the specimen processing area according to their final testing destination. The cart then travels to the appropriate clinical instrument where the specimen racks are unloaded by a human scale robotic arm. The cart will recycle to the processing area while robotic arms load each instrument. If a given instrument is replaced, the arm could (would) be reprogrammed and retrofitted to accommodate the new container shape, and automation will continue with minimal interruption and would be accomplished at nominal cost.
A single Robocart will be able to transport specimens to nearly all work areas of the laboratory. This would include automated instruments as well as providing specimens to the Pick N Place stations and the other sixteen projected stops. Command of other devices through the use of X-10 technology further enhances the utility of this robotic concept.
A further projection for the use of Robocart might be found in interfacing to front-end processing units. Specimens would initially arrive at a “stockyard” where unique features of the bar code delineate specimen destination. A robotic arm would move bar coded specimens from the stockyard to instrument specific racks located at defined places on the Robocart. An alternative would be to have multiple Robocarts with each assigned to specific station(s). The unit(s) would then transport the racked specimens to the specific instruments, automating the process without the major expense of conveyor systems.
This automation platform may not provide answers to all Laboratory Automation questions, but it does offer a novel, flexible, and inexpensive approach for the small to medium sized laboratory. As demonstrated by MARC, this approach to automation can be used for most of today's instruments without concern for obsolescence. Laboratory operating costs may be reduced without the requirement of major capital outlay. Although the project is not complete and final cost figures are, therefore not available, the “average lab” processing 500–3,000 specimens a day, should be able to incorporate this degree of automation for less than $ 350K This staged approach to automation allows more control over process development and does not appear to hold as many risk and potential limitations as other, more expensive approaches to laboratory automation.