What Is in the Contract?
Planning and Understandings
Scope of Work: Partial Supply versus Turnkey
In the case study presented here, which represents the largest APS in the world, the contract called for a turnkey scope of work. This means that the supplier, based in Florida, took on the complete design and organized the local building permits, manufacturing, shipping, installation, and testing of the parking system, including 15 years of maintenance and operations. While there might be some temptation to shop around for a number of suppliers to provide various elements, such as the manufacturing, support structure, installation and software—presumably to save money or channel work toward regular suppliers—the potential for error and failure increases to an unacceptable level. In such a large and sophisticated project, choosing a turnkey scope of work from a trusted, experienced, and proven supplier is by far the best path forward.
STEP BY STEP: MANUFACTURING AND INSTALLING AN AUTOMATIC PARKING SYSTEM (APS)
First Manufacturing Step: Machine Fabrication
The APS consists of machines that are built to support independent motions on all three axes—vertically between floors, horizontally in a row, and in/out—to move cars into and out of racks in the steel shelving system. Multiple independent machines performing the same tasks are key to the system’s reliability.
Raw steel is fabricated into frames for the different machines that move the cars inside the system. Once the frames are painted, mechanical components such as motors, gears, etc. can be installed.
Lower carrier modules with turntables rotate cars 180 degrees so that the car is returned to the owner facing forward for easy exit. These machines also move cars horizontally along a row in the APS. The machines are manufactured using off-the-shelf components from U.S., Japanese, and German producers.
Upper carrier modules move cars horizontally along an upper level. Rack entry modules move the car from a carrier into a parking slot. Carriers and rack entry modules fit together as a unit. Components for the entry/exit terminals are then fabricated.
Raw steel is fabricated.
Machines and Reliability
At least two of each type of machine are installed per area in the automatic parking facility for redundancy. Both of the machines can perform the same tasks at the same time. Therefore, if one machine needs maintenance or repair, there is always a backup machine to keep the cars moving into and out of the garage. No single failure will ever result in the system being inoperable. Performance for the manufacturer’s parking systems, based on operations and maintenance data over the past 25 years, is 99.9 percent uptime.
In the Al Jahra Court garage, 210 machines are used for the 2,314 spaces, for example. If one machine fails or needs maintenance, this is only 0.48 percent of the total robots in the garage. The only consequence of a robot failure is that a few cars take a little longer for retrieval. The certified average retrieval time for cars at this garage is 177 seconds, or less than 3 minutes. This is much quicker than the time it takes a user of a conventional garage to walk into a facility, use the stairs or elevator, find where s/he parked the car, back out of the space, navigate around other cars and people, drive down the winding ramps, and finally reach the street level. In the automatic system, the user indicates while in the lobby or via smartphone application that s/he is ready to retrieve the car, and the system does the rest, delivering the car into a terminal in just a few minutes. It is widely considered to be a satisfying user experience.
Mechanical components are added to the frames.
Electronics
While the frames and electro-mechanical components are being assembled for the automatic parking machinery, the major electrical panels as well as the electrical boxes for individual machines are prepared. The APS uses only off-the-shelf, high-quality electrical and mechanical components with L10 lifetimes of 40,000 hours or above.
All major components have at least one backup. True redundancy translates into a greater level of reliability and ensures uninterrupted operations. No single failure will ever result in the system being inoperable. Uptime of the system is unprecedented.
Electrical panels are assembled, tested, and prepared for shipment to the job site. Electrical boxes for individual machines are assembled for installation on the machinery. Additional electrical components such as sensors, wireless radios, and other items are assembled for shipment to the job site.
Electronics are added to the machinery.
Testing and Certification Before Shipping
To ensure quality control, every machine is tested and certified before it is shipped.
A newly built system is tested at the factory.
Packing and Shipping
After the APS machines are tested and certified, they are packaged along with other components for shipment to the job site. Machinery, electronics, and equipment are loaded onto trucks or into containers for shipment to the job site. Clauses in the model contract help ensure a smooth transition to the site.
System elements are packed for shipping.
Systems elements are packed into a shipping container.
Sequence of Documents Pertaining to Contract
The several documents forming the contract are to be taken together, with each explaining the others. But in the case of discrepancies and ambiguities, the priority of the documents should be spelled out. Here is an example of priorities of documents:
- Agreement
- Owner letter of acceptance, if any
- Conditions of contract
- Supplier proposal signed and accepted by owner (including cover letter, if any)
- Attachments and all related correspondences
- Any other document forming part of the contract
Contractual Relations Between Parties
The APS contract should be prepared in accordance with sound international practice for the design and execution of special installation and automation work. It should consider the general practices and customs prevailing in the market. Of course, care should be taken to maintain a balanced contract, giving due consideration to both owner’s and supplier’s rights and obligations.
A clear chain of command is necessary. In addition to the owner, the supplier should be responsible to report and take orders only from one entity, namely the consultant or owner’s representative, project manager, or engineer, as spelled out in writing.
Plans and Boundaries Clearly Defined
The contract needs to specify who does what. The supplier should be responsible only for the assembly and installation of the APS, including associated trades inside the confines of the actual parking building.
Specific Quality Standards Need to be Spelled Out
However, the supplier should be responsible for preparing all of the submittals in compliance with the standards that apply to APSs. The include NFPA 13/ NFPA 88A-2019, ASME B30.13, as well as the “Guide to the Design and Operation of Automatic Parking Facilities,” as published by NPA and the Automated and Mechanical Parking Association (AMPA).
Notice
