Water Walking Machine

Walking or jogging in water is an excellent exercise that offers several benefits over land and treadmills. It reduces joint stiffness, is less strenuous and can improve gait after injury.

The invention is a device for walking on water having a pair of buoyant hulls longer than wide with a number of propulsion flaps mounted on the bottom. The flaps are hinged and fold into the hull creating cup-like resistance chambers when hinged open to offset the rearward force of the wearer.

Object of the Invention

The object of the invention is to provide a device which allows one to walk on water without any external assistance. The device consists of a pair of buoyant hulls, longer than they are wide and having a number of propulsion flaps mounted on the bottom. The flaps fold into the hull and create cup-like resistance chambers which offset the rearward force of the user. They then rotate inwardly when the hull is urged forward.

The device also has a footwell located in each hull and a resilient shoe attached into the footwell. The shoe may be made of a soft rubber and/or polyurethane material, such as PVC. The shoe may have a hook and loop tape fastener for attaching the front of the shoes to the floats or a spring like clip around the open top of the shoes which is attached to the float’s bottom.

To disengage the device in the event of a fall into the water, the user simply relaxes his/her feet and pulls them away from the resilient shoe, separating the VELCRO or opening the clip. A tether attaches the float to the footwell of each hull at the user’s ankle height.

While the concept of walking on water has been known for a long time, the idea of a device that permits such walking has not been developed until recently. Earlier devices, including those patented in the 1858’s, were primarily a means to prevent one’s feet from spreading apart and slipping on the surface of the water.

However, those designs lacked the necessary stability in the hulls and the propulsion flaps needed to propel a person walking on the water. This was the challenge for Mr. Rosen, who had been searching for the right combination of a durable, buoyant hull and propulsion flaps for years.

His device, he said, is “a water-walking micro-robot.” The sturdily constructed pontoons, which are Water walking machine made of Styrofoam and plywood, have flaps hinged to them that mimic paddles. They swivel from 9 o’clock to 12 o’clock and are not heavier than the water they walk on, unlike flaps on other designs.

Propulsion

A water walking machine is a personal propulsion device that can be used by a human user to propel themselves across a body of water using natural walking motions. The apparatus includes a floatation device, a harness attached to the user’s torso, and a pair of paddles. The paddles are designed to have upper ends that pivotally interconnect with the harness, and lower water engaging ends that may be moved in a paddling motion in a generally fore-aft direction relative to the harness.

In nature, various insects and reptiles can walk on water by utilizing different propulsion principles based on the mass transfer phenomena between two fluids with different surface tensions. One such principle is the Marangoni effect. Inspired by this principle, this study develops a battery-less self-propulsion microrobot that uses water imbibition powered microfluidic pump to generate thrust without the use of an external mechanically driven actuator or other forms of moving parts.

The micro-robot is equipped with a wireless photonic gel sensor to sense the external environment and transmit the obtained information to the water walking machine. It is also integrated with a magnetically triggerable, water-imbibition powered microfluidic pump to propel at the water-air interface by the Marangoni effect.

We developed a prototype of this micro-robot. To actuate the robot, we used a combination of an amplified vertical bending motion and a back-and-forth rotation angle of each actuating leg to create a sculling motion. This sculling motion is similar to the elliptical trajectories of the legs of a water strider, which enables the robot to move forward or turn, like that of a real water strider.

When compared with an identically-sized FP-equipped micro-robot, the propulsion behavior of the CP-equipped micro-robot was characterized by a fast and steady speed in a short duration, owing to the relatively faster water-imbibition rate induced by the porous media than by the FP. This characteristic was attributed to the fact that premature contact between alcohol and water surface, and the dynamics during alcohol-to-water coalescence play an important role for efficient locomotion (Fig. 5A).

To further enhance the directional movement and improve the efficiency of locomotion, we explored the influence of four key parameters on the micro-robots’ performance including porous materials, keel extrusion, nozzle diameter, and footpad height (hf = 6.5 or 9.5 mm). The results revealed that when hf was 6.5 mm, smaller Taw enhanced Sd and eK,max at the expense of velocity.

Stability

Water walking is a popular and low-impact form of physical exercise that can be used by anyone. It helps to strengthen muscles, burn calories and improve balance. It can also be beneficial for individuals with arthritis or other joint disorders. It is recommended that users wear hand webs to help them maintain their balance and avoid falling over the sides of the device.

There have been a number of studies to develop water-walking robots with actuators, such as piezoelectric and shape memory alloy (SMA) actuators. However, these actuators have limitations in actuation strain and power consumption. These limits can prevent them from being lightweight and high-speed. In this study, we applied a compliant amplified SMA actuator (CASA) to achieve a water-walking microrobot capable of moving forward and turning with four degrees of freedom.

We also designed the sculling motion of the actuating leg to mimic the sculling motion of a real water strider to generate a desired trajectory for the robot. To achieve this, we placed the actuating leg through two holes in a pair of moving frames designed to move in different directions perpendicular to each other. The sculling motion of the actuating legs enabled our robot to move forward and turn without touching the water. Moreover, when the SMA wire was turned off to lower the leg, it returned to its initial state due to the elastic beams of the SMA actuators.

When the SMA wire was on, it had to be cooled down to avoid input energy to the actuator. The sculling motion of the SMA actuators created a desirable elliptical trajectory of the actuating leg. This trajectory enabled the robot to turn by swinging both actuating legs simultaneously or by swinging only one actuating leg.

Our water-walking microrobot was capable of moving forward and turning by swinging two actuating legs simultaneously or by swinging one actuating leg with another leg resting on the water. It also was able to perform Water walking machine a vertical motion by swinging one actuating leg with the other resting on the water.

The invention has a pair of buoyant hulls longer than they are wide, with propulsion flaps mounted on their bottom surfaces. These flaps fold into the hull to create cup-like resistance chambers when hinged open to offset the rearward force of the user and increase forward movement. A footwell is located in each hull, the bottom of which is below the waterline and near the center of gravity. A resilient shoe is attached into the footwell for a connection between the wearer and the apparatus.

Footwell

A footwell is located in each hull slightly wider and longer than a person’s foot. The bottom of the footwell penetrates into the hull below the water line near the hull center of gravity. It is narrower at the top than the bottom, however, allowing one’s foot to enter and provide support for their ankle decreasing the susceptibility of tipping in the water.

The footwell may be lined with a resilient material and is preferably made from the same material as the rest of the hull. It is a good idea to have a hand grip 65 on each hull immediately rearward of the footwell for mounting the device from the water.

In addition to the footwell, a propulsion fin 52 is mounted under each hull having swinging side panels 54 on each vertical surface providing stability in the water and increasing the surface when forced rearwardly. These panels fold flat against the fin when slid forward, in the same manner as the flaps 22, which also function as a rudder.

This device can be adapted to accommodate variable spacing between the pontoons with a platform support which expands and contracts when in use to accommodate this adjustment. The platform supports may have a curved saddle which straddles over the curved outer surface of the pontoons securing it to the pontoons.

An optional, removable stabilizing arm 72 upstanding from each hull forwardly adjacent to the footwell provides a support handle for grasping to assist in stabilizing the hulls when walking on the surface of the water. The arm may include a grip 76 on the upper portion to provide a comfortable, easy-to-grasp surface for grasping.

Alternatively, a storage compartment 56 may be disposed within each hull and covered with a waterproof covering to allow for stowing ancillary gear therein. The cover is secured to the hulls with keepers embedded into the hulls adjacent to a pair of flaps and a tension member stretched therebetween in such a manner as to hold all the flaps in a retracted position for transportation and storage.

A one-way check valve 66 is positioned between the bottom of the footwell and the underside of each hull to allow water trapped inside the footwell to be drained by lifting the hull above the water. The check valve may be any type suitable for the application such as a ball and resilient seat, or the like, well known in the art.