ARGOS Optimization Suite

The ARGOS Optimization Suite is a set of applications built upon On Time Systems' proprietary optimization technology that provide dramatically improved schedules for major construction projects including shipbuilding, fleet maintenance, and refinery turnarounds.

ARGOS Optimization Suite Diagram
ARGOS is the only scheduling system that directly targets efficiency of resource usage as its optimization metric.

The Need for ARGOS

Shipbuilding and similar labor-intensive industries requires relatively skilled and expensive labor. For example, approximately 30% of the cost of a new ship is labor, and existing scheduling systems are not designed to improve the overall efficiency of labor utilization.

Billions of dollars are wasted annually in complex, large-scale operations due to the limitations of existing planning and scheduling methods. These methods are a combination of conventional wisdom, experience, and software systems that are only capable of finding a solution, without the ability to evaluate or find a high-quality solution. Complex construction operations involve thousands of decisions regarding task timing and resource utilization. If these choices are well made, good outcomes can generally be expected. If even a few are poorly made, however, the result may be much worse than it might otherwise have been. The choices with which we are presented typically interact in subtle ways that only become apparent after many other choices have been made, so the best choices can only be determined by exploring the various combinations of decisions that are available.

Real World Applications

Commercial Ship Construction

The world's commercial shipyards are facing heightened economic pressures due to increasing competition and globalization. This has stressed shipyard bottom lines, causing them to demand more effective use of resources to reduce costs and increase productivity. The workloads in the world's largest shipyards typically overwhelm the optimization capabilities of scheduling products other than ARGOS, making it infeasible to create schedules that reasonably consider everything going on in the yard. At best, schedules for individual ships are maintained independently, with manual processes used in an attempt to coordinate resource usage and throughput among projects. Schedules typically take so long to produce that it is impractical to reschedule inside the production cycle when things go wrong. These conditions create a tremendous opportunity for ARGOS, which can schedule multiple years' production in the largest shipyard in hours while still achieving significant cost savings, reducing labor-use fluctuations, and responding to the changing production situation in a timely way. Annual savings in the commercial shipbuiling market could exceed $2 billion, simply through better utilization of existing shipyard resources. ARGOS is the only technology available that specifically targets realization of these savings.

Naval Ship Construction

Ship and submarine construction for the US Navy is done by US domestic shipyards. Unlike international yards, which typically compete on ships on a commodity basis, American yards typically compete for Navy business in much more complex ways. While cost is not necessarily the only (or even the primary) consideration, American yards nonetheless are under great pressure from the Navy and congress to manage their costs. While cost savings do not necessarily flow directly to the bottom line, congressional decisions about the number of ships to be built appears to be closely connected to the perception of value for the dollar and cost control. ARGOS provides tools that would let yards make significant progress on these important metrics.

Refinery Turnarounds

Oil refineries need periodic complex overhauls (called turnarounds). Turnarounds involve thousands of tasks over a period of weeks, during which production must be shut down, at a cost of millions of dollars per day. Managing turnarounds requires balancing the costs of downtime and labor (often including housing workers in remote areas), as well as addressing competition for access to limited space. ARGOS is ideally suited to such complex, large-scale, optimization tasks.

In addition to cost issues, shipyards, and in particular American yards, also have significant difficulty attracting and retaining the skilled workers needed in shipbuilding because of the churn in the labor force. When orderbook fluctuations cause significant shipyard disruption, workers laid off by a shipyard are likely to find employment elsewhere and be unwilling to return to shipyard work when they are needed. Similarly, unpredictable overtime levels tend to disrupt workers' lives, which negatively affects productivity and retention. ARGOS can help with this problem by engineering smooth workforce profiles and by minimizing the number of workers who might otherwise be considered excess during slow or idle work periods.

ARGOS' advanced float-management capabilities, together with its ability to adaptively reschedule within the production cycle as actual conditions deviate from planned, mean that shipyards can reduce their vulnerability to unplanned disruptions of the ship construction schedule. This helps reduce risk by controlling milestone slippage and the need for workforce fluctuations, as well as by allowing on-the-fly replanning to avoid costly disruptions.

The ARGOS Approach

ARGOS is OTS' flagship optimization product: a schedule optimization tool that is intended to work in tandem with project management and project scheduling systems, improving labor efficiency in large-scale construction and maintenance projects. ARGOS is the only scheduling system that directly targets efficiency of resource usage (i.e., cost) as its optimization metric.

ARGOS relies on a fundamentally different algorithm than traditional scheduling systems, which provides a variety of advantages. This algorithm lets ARGOS balance numerous, possibly conflicting, objectives instead of simply trying to minimize duration. The ability to optimize for many different criteria simultaneously gives ARGOS the flexibility to meet varying shipyard needs. In addition, ARGOS’ speed makes it possible to re-optimize in response to situational changes and to develop new plans inside the production cycle, offering shipyards and other industries the potential to recapture billions of dollars currently “left on the floor” each year.

ARGOS Results

ARGOS can help reduce labor costs by roughly 10% through better resource utilization (less overtime and less idle time) in addition to improving the chances that the schedule can be executed as designed and determining the optimal workforce size to have available as a project progresses.

ARGOS Features and Benefits

  • Shipyard-specific Optimization Metric
  • High-speed Optimization
  • Warm Restarts
  • Manpower Planning Tool
  • Float Optimization
  • "Smart" Float
  • "Anytime" Behavior
  • Better Manpower Management
  • Integration with Existing Shipyard Scheduling Software
  • Schedule visualization
  • Tailorable to Different Customers
  • Adapts to Changing Needs
  • Solve Large Problems
  • Faster Response to Schedule Disruptions
  • Computes Optimal Staffing for Given Schedule Choices
  • Customizable Tradeoff between Schedule Robustness and Cost
  • Emphasizes Float Where Slippage Is Most Damaging
  • Good Solutions Available Quickly
  • Reduces Levels of Overtime and Idle Time
  • Reduces Staffing Churn
  • No Disruption to Existing Reporting and Scheduling Processes
  • Allows Rapid Assessment of Schedule Quality
  • Rapid Insertion into Production
  • Accommodates Business Change
  • Optimization Inside Production Cycle
  • More "what-if" Analysis
  • Minimal Cost/minimal Disruption Options
  • Allows Optimal Management of Labor Pool
  • Customers Can Control the Level of Slack and See What Extra Slack Costs Them
  • Makes Schedules More Robust Without Unduly Increasing Cost
  • Computation Effort & Lead Time Responsive to Situational Needs
  • Lower Costs, Less Burden on Workforce, Better Retention
  • Small Integration Costs
  • Minimal Training Time and Cost
  • Increased Ability for Schedulers and Others to Produce Schedules with Desired Qualities

Further Details

ARGOS Case Study - Shipyards

Approximately $100 billion is spent annually on the construction, refit and repair of commercial and naval vessels. New commercial construction is performed at hundreds of shipyards worldwide for commercial shipping companies that carried about 6.8 billion tons of cargo by sea last year (over one ton for every person on the planet).

The problem of developing schedules that make efficient use of shipyard resources is critical, both to control costs and to meet needs regarding available resources, be they time, dry dock space, or skilled manpower. Both construction and maintenance are extremely complex processes, involving thousands of activities with thousands of constraints among them. This complexity makes it virtually impossible for people, even augmented by the commercial scheduling systems available today, to find good schedules.

If the goal in scheduling is to manage resource usage, the most effective way to achieve that goal is for the scheduling system being used to target resource management directly. Experiments at several US shipyards indicate that doing this can save over 10% of total labor costs, and ARGOS is unique in providing this functionality. These savings are achieved without changing the fundamental production process or shipyard facility in any way.

Figure 1 shows a typical project from an actual shipyard. The top histogram shows the results of the ARGOS optimization, while the bottom histogram is the resource staffing profile of the original schedule. Not only is the ARGOS profile smoother and flatter, it also maintains a desirable ramp-up and ramp-down shape. Note that the original profile peaks at around 1900 workers on staff, while the ARGOS profile peaks at around 1500; both schedules start and end at the same time.

Comparison of original schedule and ARGOS optimization (resource usage)
Fig.1: Comparison of original schedule and ARGOS optimization (resource usage)
The black line in the figure shows the resource level (i.e., the total workforce size) on site for this project. The red areas indicate overtime; any difference between the top of the green area and the black line indicates undertime (or idle time). Note the significant gaps between the resources on staff and those needed in the first half of the original schedule; those gaps correspond to significant idle time expense and have been eliminated in the ARGOS version of the schedule.

Figure 2 shows the same histograms, but now colored by how critical each task is. A task that cannot "slip" without delaying the entire project is colored red, while a task that can slip significantly is colored green. The user controls the way in which ARGOS trades off the optimization criteria of schedule cost and robustness, since these two desiderata often compete with one another. Thus the user can easily create a more (or less) time-critical schedule simply by adjusting a slider and running ARGOS again. In the figure, note that the ARGOS schedule is "greener" than the original schedule, with the critical red tasks at the middle and end of the original schedule having been moved to a time where there is potential slack in their execution. From an operational perspective, this means that the ARGOS schedule, in addition to being cheaper to execute, is more likely to be executed successfully.
Comparison of original schedule and ARGOS optimization (criticality)
Fig.2: Comparison of original schedule and ARGOS optimization (criticality)
Figure 3 displays a final perspective on the same project, and shows that the ARGOS schedule is over 10% cheaper than the original. Further detail provided by the ARGOS GUI is not shown here, but includes a variety of other perspectives on similar information and the recommended start date and time for each of the activities that ARGOS moved in order to achieve its results. These other features were designed after extensive consultations with schedulers at a variety of American yards.
Cost summary of original schedule and ARGOS optimization
Fig.3: Cost summary of original schedule and ARGOS optimization

Simyard Savings

As part of the Navy's ongoing evaluation of ARGOS, On Time Systems developed SimYard, a shipyard simulation system. SimYard allows schedule performance to be simulated under the uncertainties and inefficiencies experienced in real yards. SimYard was evaluated by independent stochastic simulation experts, who pronounced its methodology both sound and highly innovative. The simulator has been instrumental in demonstrating that the schedule savings projected by ARGOS are likely to be realized by any shipyard that deploys the technology despite the vagaries of shipyard operations. As part of the ARGOS Optimization Suite, SimYard is used as a shipyard evaluation tool to augment the functionality provided by ARGOS, providing further insight into shipyard operations and productivity.

ARGOS SimYard GUI