PropellerSafety.com

Archive for inventions

Many have accused the boating industry of suppressing the development and deployment of propeller guards and other propeller safety devices.

A list of ways in which the boating industry has been accused of suppressing propeller guard inventions, technologies and other propeller safety technologies is provided below. They are grouped by events or topics and partially organized by timeline.

Please Note

We try to keep the Propeller Guard Information Center / PropellerSafety.com fair and objective on propeller safety issues. However, as is often the case in discussing the suppression of other technologies, this list includes several unproven accusations and claims made by others. We are not saying we believe every single one of these points or that every one of them is true. Several of these points are based on circumstantial or hearsay evidence. You will need to make your own judgement call as to the truthfulness of these statements.

Many of these accusations have been made previously. Those with experience in this field may harbor emotional feelings for or against several of the points made here. To our knowledge this is the first large scale collection of these claims.

For those who feel many of the points made here are untrue, we remind you that for the boating industry to have suppressed propeller safety inventions and technologies ONLY 1 of these over 140 points needs to be true. For the industry to have willfully suppressed propeller guard and other propeller safety technologies you will need to decide how many of them are true and if in your opinion those particular points create the preponderance of evidence necessary to indicate willful intent. Read More→

1 Categories : Legal Shorts

Our Detecting People Near Boats More Reliably Using Optical Image Stabilization invention disclosure below was posted on 19 September 2012. We will make no changes to the text below the line following this paragraph except to correct misspellings, punctuation, and to update html/computer codes and links. Any updates to the invention will be posted below the invention disclosure.


Detecting People Near Boats More Reliably Using Optical Image Stabilization Invention

This invention has to do with improving the reliability of virtual propeller guard systems designed to detect people in the water near boats that may be in danger of being struck by the boat’s propeller. Read More→

RingProp

RingProp safety propeller

Several years ago, a UK firm tried to commercialize a ringed propeller from Australia called RingProp. The propeller was said to be safer than traditional propellers because human limbs could not easily enter between the blades. When the propeller was spinning it created a shroud around the blades.

Efforts to develop RingProp were spread over at least two decades, two continents, several firms, and one stock exchange. We previously covered the history of RingProp hoping other firms might learn from their efforts and avoid their mistakes.

Liquidators have now placed the intellectual property behind RingProp for sale at Edward Symmons, a UK property and asset consultancy. Read More→

4 Categories : Guard Technologies

Marine drive companies have long employed damping / cushioning technologies to protect marine drives, most typically trim cylinder log strike systems that allow the drive to swing back, up, and over underwater obstacles. Recent years have brought several through hull drives to the market, most prominently Volvo Penta’s IPS, and Brunswick’s / Cummins Mercruiser Diesel (CMD) Zeus Pod Drive.

CMD Zeus Drive

Cummins MerCruiser Diesel (CMD) Zeus Drive

These thru hull drives, typically used on larger boats, are no longer able to be protected by the trim cylinder log strike systems because the drives do not trim. Volvo Penta and Mercury Marine / Brunswick have been issued several patents for break away drives and other techniques to protect the drive and especially to prevent the boat from sinking if the drive strikes a major obstacle, like a large rock.

In November 2011, Brunswick was issued U.S. Patent 8,062,082 for a “Marine Drive With Staged Energy Absorption Capability”. Targeting through hull drives, the patent describes a drive with a long, crushable nose cone. Depending on the amount of energy to be expended when a drive strikes an obstacle (speed of boat and mass of the boat), the nose cone can crush to absorb the energy, or the drive can “breakaway” from the boat. At lower energies (lighter boats and slower speeds) the nose cone crushes to absorb the energy, slow the boat, protect the main part of the drive, and prevent the boat from stopping so fast that people would be ejected. At higher energies (heavier boats and faster speeds), the drive breaks away in a manner that maintains the integrity of the hull and prevents water from entering the boat. The patent includes several charts showing the deceleration capabilities of varies designs. Brunswick introduces the idea of not only crushing the nosecone to absorb the energy, but also of allowing water to fill the nosecone, then forcing it out through one or more orifices during a collision, of filling the cone with an impact absorbing structure, filling the nosecone with an energy absorbing foam, and review previous approaches by others.

The industry is identifying technologies that can protect the boat, and the drive, and do so in a way that does not cause sufficient rapid deceleration to eject people from the boat.

Some of the earlier technologies, and the some of the more recent developments appear to hold significant promise for being able to reduce the impact / blunt trauma felt by humans when struck by a propeller guard. Anything that can reduce the rapid acceleration felt by humans when struck by a marine drive or guard AND the duration of that acceleration is a candidate for reducing injuries and their severity.

We anticipate publishing a post on the science behind blunt trauma injuries in the future which should also be a helpful reference to those pursuing this project. For those not familiar with blunt trauma injuries or who just think of them resulting from being whacked or hit with something, blunt trauma injuries result from sudden accelerations or sudden decelerations. Our organs, tissues, and even bones are damaged when they are accelerated or decelerated too quickly. Blunt trauma injuries can be reduced by reducing the peak accelerations and decelerations of humans struck by propeller guards.

We propose students consider Cushioned Propeller Guard design projects for their Senior Design Projects, Sr. Thesis, and Capstone projects to better protect humans and marine life from being struck by a propeller guard, and provide further information below. Read More→

0 Categories : Research Projects

Boat propeller guards create drag which effects the performance of the boat, especially the top speed attainable at wide open throttle and time to plane. Propeller guard designers try to minimize drag by increasing the size of the mesh (make the open holes larger) and by decreasing the size of the wires / rods used to construct the mesh. However, those actions begin to reduce protection provided by the propeller guard, its rigidity and its strength. Prop guard designers make these tradeoff without an in depth understanding of all the variables involved.

We propose further research by students as Senior Design Projects, Sr. Thesis, Masters Thesis, and Capstone projects on the drag created by the components (meshes, screens, wire, rods, struts) used to construct propeller guards in clean flows and in the turbulence present in their operating environment. Read More→

0 Categories : Research Projects

Today, August 29, 2011, we, the Propeller Guard Information Center, posted five RFID (Radio Frequency Identification) invention disclosures. While they have other implications as well, they were primarily inspired by problems surrounding boat engine kill switches (emergency engine cut-off switches).

We (Polson Enterprises and the Propeller Guard Information Center) initially retained all rights to these inventions (including their use in non-boating applications). However, one year later (29 August, 2012) all five inventions were placed in the public domain.

Existing lanyard boat engine kill switches (emergency engine cut-off switches) are used to kill the engine if the operator falls overboard. Boats often begin spinning wildly in the “Circle of Death” after the operator has been ejected. A boat operator that falls overboard while the boat is underway may be struck repeatedly by the boat and/or propeller as the boat circles.

Lanyard boat kill switches are rarely used by boat operators due to the hassles of hooking them up. Sensor based kill switch systems such as Autotether and MariTech’s Virtual Lifeline and CAST have began to address some of the hassles involved with using lanyards. Our RFID tag based invention disclosures illustrate a different sensor based approach with some additional advantages.

Our five invention disclosures are: Read More→

Our RFID Clothing Used to Detect Human Presence in Boat Kill Switch Applications invention disclosure below was posted on 29 August 2011. It is one of five related Radio Frequency Identification (RFID) invention disclosures we posted today. We will make no changes to the invention disclosure that begins with text below the horizontal line following this paragraph except to correct misspellings, punctuation, and to update html/computer codes and links. Any updates to the invention will be posted below the horizontal line marking the end of the invention disclosure. Read More→

Our non-unique RFID Fob / RF Reflector Used to Detect Human Presence and/or Human Proximity and/or Human Location invention disclosure below was posted on 29 August 2011. It is one of five related RFID invention disclosures we posted today. We will make no changes to the invention disclosure that begins with text below the horizontal line following this paragraph except to correct misspellings, punctuation, and to update html/computer codes and links. Any updates to the invention will be posted below the horizontal line marking the end of the invention disclosure. Read More→

We created this Propeller Safety Inventions category in August 2011. I am listing some of our earlier inventions and linking to them here. We will be posting our future inventions in this category.

If PGT<2011 is beside the invention, more can be read about it on our Pre 2011 Propeller Guard Technologies page at the date provided. Some are thoroughly described, others are just briefly mentioned. Read More→