The Net Vessel Movement Model, or NVM2, is a dynamic mathematical model that Race Recon developed specifically for the longest ever two-man kayak expedition, Crossing the Ditch.
NVM2 is a decision support model that we developed to simulate the expedition several times before the team actually left. We found out about the seasonal impact of the EAC, the influence the sea-anchor had in favourable and not-so favourable conditions, and the amount and type of food and water required to successfully conquer a world first.
When Race Recon analyse a system, such as the World’s First Trans-Tasman Kayak Expedition, to be controlled or in this case optimized, we build a mathematical model. We build a descriptive model of the system as a hypothesis of how the system could work, or try to estimate how certain events might affect the system. Similarly, in control of the system, we try out different control approaches in simulations to support decision-making on the actual expedition and forearm the team with likely outcomes given a certain set of circumstances.
Race Recon model’s usually describes a system by a set of variables and a set of equations that establish relationships between the variables. The variables represent some properties of the system.
How does it work?
Assumptions
NVM2 bases the net movement prediction on key performance assumptions relating to the vessell and the impact other variables have as well. This data can be based on a best-guess or confirmed by actual testing for specific assumptions. These may include
- Vessell speeds at differing intensity
- Vessel drift in current/wave/wind
Inputs
Moves
NVM2 can predict on move at a time or thousands of consecutive moves. The team decide on a time based sequence of decisions on issues such as
- Paddle Direction
- Paddle Intensity
- Rest/Sleep Times
- Anchor/Drogue Deployment
- Energy Intake
- Water Intake
- Fatigue
Environment
NVM2 takes the decisions made for that move and consults a number of databases on the following environmental information relating to the date and time you wish to simulate.
- Sea Surface Current Direction and speed
- Significant Wave Height and Direction
- Wind speed and direction
- Water Temp
- Air Temp
Outputs
Calculation
All of these inputs are then considered by NVM2 and the assumptions determine how each layer of data interacts another ultimately predicting a position in latitude and longitude where the vessel is likely to be given those decisions and conditions.
Outputs
NVM2 also computes a multitude of environmental, physiological and expedition specific information such as
- Efficiency Rating
- Energy Balance
- Water Balance
- Rest/Sleep Ratio’s