Electronic devices and systems are playing an ever increasing role on marine craft for the navigation of bodies of water. For instance, the use of Global Positioning System (GPS) technology, to locate a marine craft on a body of water, coupled with electronic navigational maps allows the driver of a marine craft to chart location and course of the craft. Further, such electronic devices can allow the driver to navigate the marine craft by viewing the information displayed on a monitor, contained in a hand held unit, on an instrument display, or in a device such as a fish finder, sounder, chart plotter, or the like.
Additionally, advancements in sonar technology, since its inception in the late 1930's, has enabled marine craft users to identify the depth and the terrain type and structure of the bottom of a body of water as well as objects suspended within the water between the sonar transducer and the bottom of the body of water. More recent refinements in this technology have also seen sonar units decrease in size, allowing for their use on personal marine craft and experienced refinements in the device's ability to view objects. Marine and sport fishing enthusiasts now embrace this technology's ability to identify underwater objects as small as fish, weeds, thermo-clines, and the like. These advancements have allowed users, for example in the field of diving, to find wrecks, bottom features, and animals upon which they would be interested in diving to see, and have been utilized in the field of fishing to identify potential fishing spots for an angler.
Systems that utilize a sonar device can also utilize a temperature sensor to identify the surface temperature and in some instances can identify the temperature in different regions below the surface. The ability to identify the temperature of the water near the marine craft is of particular interest to fisherman, because it is generally known that the temperature of the water in which the fish are located effects their behavior patterns and feeding locations. For example, temperature can play a role in activities such as, feeding and spawning. Temperature can also play a role in nurturing a food supply for the fish and, therefore, an area with a temperature conducive to nurturing the food supply can also have feeding fish. Anglers believe that it is during aggressive periods, such as during feeding and spawning, that a fish will more readily ingest bait presented to it.
Accordingly, many anglers believe that by locating an area within the body of water wherein the temperature of the water is within a specific target temperature range, that they are able to more readily catch fish. Since identifying a location that has a water temperature within a specific temperature range can be a key element in locating fish that are feeding or spawning, the monitoring of temperature can be a key to fishing success.
Temperature sensors have been developed in many forms, for example, sensors have been devised that are attached through the hull of the marine craft or to the transom of the marine craft. These types of devices have generally been capable of measuring the temperature of the water at or near the surface of the body of water. Additionally, sensors have been developed that are lowered to a desired depth wherein the temperature is measured by the sensor. These devices typically have a waterproof temperature sensor unit connected thereto by a long conductive cable. The sensor can then be lowered into the water and the temperature measured at a desired depth.
Temperature information has heretofore been displayed on the monitor of devices and systems such as, for example, fish finders, sounders, plotters, marine craft instrument panels, and the like. The information is sometimes displayed as a running line plot that indicates the temperature either versus time or versus depth. Alternatively, in some applications, the information has been displayed as a numerical measurement of the temperature measured by the sensor, for example, as 69 degrees Fahrenheit or 20 degrees Celsius. However, the display of temperature information in these ways does not allow the user to see trends in the water temperature data or to see the location of the marine craft relative to the edge of the water having the desired temperature range.
Since, in some marine situations it is desirable to remain within, or in proximity to, water having a specific temperature range, audible and visual alarms have been developed to alert the driver of the marine craft that the craft has moved out of an area of water having temperature within the desired range. For example, one prior art device is capable of setting an alarm that sounds an audible alarm when the marine craft is within a preset range of temperatures. Alternatively, the device can also be set such that the audible alarm will sound when the marine craft is outside of the range. However, the use of these alarms does not allow the user to see how quickly they are approaching or leaving an area of desired temperature or to see the location of the marine craft relative to the edge of the water having the desired temperature range.
Prior art devices utilizing visual alarms, have utilized text messages, for example, stating that the marine craft has moved outside the temperature range and have utilized signals such as a flashing light to indicate that the marine craft has gone outside the preferred area. However, the devices are not able to monitor the temperature over a period of time, and therefore are unable to allow the driver to see how quickly he or she is nearing an area having the desired temperature or how quickly the marine craft will be exiting an area exhibiting the desired temperature range at the speed the marine craft is presently moving. Nor do these devices allow the user to know the location of the water having the correct temperature or to define an area by mapping having a desired water temperature. The information is also provided on a screen that is separate from the screen in which the temperature data is being shown and therefore, while the alarm screen is being viewed, the other functions of the device can be obscured.
Thus, there exists a need for marine craft systems, devices, and methods that can provide temperature trends, temperature history, temperature area mapping, unobstructed viewing of alarms and data, and the like.