WO2009021559A1

WO2009021559A1 - Solar-hybrid catamaran boat

Info

Publication number: WO2009021559A1
Application number: PCT/EP2007/059813
Authority: WO
Inventors: Peter Grauer; Eskil Suter; David Suter
Original assignee: Code-X Ag
Priority date: 2007-08-10
Filing date: 2007-09-18
Publication date: 2009-02-19
Also published as: EP2178744A1

Abstract

Catamaran boat (10) comprising two side hulls (11.1, 11.2) and a rigid connecting structure mechanically connecting said hulls ( 11.1, 11.2), where a passenger compartment (13) is provided in said connecting structure. The boat (10) further comprises two combustion engines (20.1, 20.2), two solar driven electrical engines (30.1, 30.2), a solar panel ( 14), and a common control system (40) for controlling said engines (20.1, 20.2, 30.1, 30.2). The control system (40) enables at least two modes of operation where in a first mode of operation said boat (10) is powered by said two solar driven electrical engines (30.1, 30.2) only, and where in a second mode of operation said boat (10) is powered by said two combustion engines (20.1, 20.2) only.

Description

Solar-Hybrid Catamaran Boat

[001] The invention relates to Catamaran boats comprising two side hulls and a rigid connecting structure mechanically connecting the hulls. A passenger compartment is housed between said hulls and the boat is powered by two engines.

[002] The priority of the German patent application with application number DElO 2007 037 828.0, filed on 10 August 2007, with title "Doppelrumpfmotor- boot" is herewith claimed.

[003] High-speed boats are typically very difficult to handle and are thus often used by experts only. The whole design and setup of these boats is so that a very stiff system for high speed racing is provided. The passenger comfort and easy of handling are issues which are typically not taken into consideration, since the respective measures would add to the weight and size of such boats.

[004] The high-power marine engines employed in high-speed boats typically have the disadvantage that they are difficult to maneuver when entering a harbor or when cruising through bays or creeks, since these kinds of engines, even if operated at or close to the idle state, are relatively fast. Furthermore, the com- bustion engines employed have a low efficiency at or close to the idle state so that they consume quite some fuel. Yet another disadvantage is the noise pro- duced by the exhaust system which is typically designed to let emissions escape from the engine easily. This means that the noise emissions of high-speed boats can be very disturbing.

[005] There are, however, situations where the high-speed boat is to be operated like many other boats, namely when entering a harbor, or when approaching a pontoon, for instance. But also when using the boat for sunbathing or swimming, the elements which are essential for a high-speed boat are rather disturbing. For instance, the passenger compartment (pilot cockpit) of a high-speed boat is very difficult to access and the entrance hatch or door is typically small.

[006] In other words, a speed-boat typically offers no luxury and no elements that would make trips comfortable.

SUMMARY OF THE INVENTION

[007] It is thus an objective of the present invention to provide a speed-boat that combines aspects of a boat designed for racing or speeding purposes with elements of a comfortable cruising boat.

[008] It is another objective to provide a boat that is suitable for daily use as well as for covering long distances in a short period of time.

[009] The present invention accordingly provides a Catamaran boat comprising two side hulls and a rigid connecting structure mechanically connecting the side hulls, where a (fully fledged) passenger compartment is provided between said hulls. The boat further comprises two marine engines and two solar driven electrical engines as well as a common control system for controlling said engines. One marine engine and one solar driven electrical engine are positioned inside each side hull. [0010] According to the present invention, the common control system is designed so that two modes of operation are offered where in a first mode of operation the boat is powered by the two solar driven electrical engines only, and where in a second mode of operation the boat is powered by the two marine en- gines only.

[0011] According to the present invention, the passenger compartment is fully fledged as compared to the small Spartan pilot cockpit of speed boats. The side hulls have a displacement volume sufficient to carry the whole boat plus passen- gers. In order to be able to offer sufficient displacement volume, the two side hulls have an aspect ratio between 0.5 < H_H/H_B < 1 (where H_H is the height of the hulls and H₈ is the height of the boat). In other words, the passenger compartment has a "ducked-down" or concealed position between the hulls.

[0012] According to the present invention, a Catamaran boat is provided since this kind of boat offers the best possible compromise when the features of a speed-boat are to be combined with the features of a cruising boat. It is another advantage of the Catamaran design that it is possible to provide a large passenger compartment between the two side hulls. Furthermore, due to the fact that the two side hulls are spaced apart, the lateral stability of the whole boat is much better. This means that the boat is more comfortable to ride than a boat with a single hull.

[0013] Due to the fact that two side hulls are provided, the Catamaran design offers room for two identical marine engines. These engines can be designed so that ample power is available to propel the boat up to very high speeds. The paired arrangement of the two marine engines adds to the lateral stability of the whole boat. A paired drive is much easier to control than a single drive, which makes the handling of the boat less challenging.

[0014] According to the present invention an independent (auxiliary) drive system is provided which is mainly operated by solar energy. For this reason a solar panel in combination with a battery or other kind of energy storage are provided. In the side hulls a pair of solar driven electrical engines (one inside each hull) is provided. These solar driven electrical engines are powered by electrical energy and thus produce no, or almost no, noise and no exhaust emissions.

[0015] It is an advantage of the paired arrangement of the electrical engines, that a very easy and straightforward manoeuvring of the boat is possible. The boat can be turned around almost on the spot and the approaching of a pontoon is a simple manoeuvre.

[0016] In a preferred embodiment, the propellers of the solar driven electrical engines are retractable so that the underwater portions of the side hulls are unobstructed when the boat is operated in the high-speed mode.

[0017] The key element of a preferred embodiment of the inventive Catermeran boat is a unique combination of two high-power marine engines and two solar driven (low power) electrical engines. This combination basically offers two boats in one and the boat thus can be operated in different modes. The high-power engines and the electrical engines interoperate and are controlled by a single stick in a very intuitive manner. A perfect configuration and placement of the propellers and rudders eliminate the dreaded spinout. The boat can be operated in a gliding mode at very high speeds using the two high-power marine engines and it can be operated in a semi-displacement mode without producing any noise or exhaust emissions, when employing the electrical engines.

Brief description of the drawings

[0018] For a more complete description of the present invention and for further objects and advantages thereof, reference is made to the following description, taken in conjunction with the accompanying drawings, in which : Figure 1 is a perspective view of a first embodiment of the invention;

Figure 2 is a side view of the boat shown in Fig. 1;

Figure 3 is a top view of the boat shown in Fig. 1;

Figure 4 is a cross-section of the boat shown in Fig. 1, where the two marine engines are shown;

Figure 5 is a schematic top view of the boat shown in Fig. 1, where the positions of the two marine engines and the two electrical engines are shown;

Figure 6 is a schematic cross-section of one hull of the boat where one of the electrical engines is visible;

Figure 7 is a schematic block diagram of some of the components and systems of an inventive boat,

Figure 8A is a perspective view of the stern end of another Catamaran boat, according to the present invention,

Figure 8B is a perspective bottom view of the stern end of the Catamaran boat of Fig. 8A, according to the present invention,

Figure 9 is a perspective view of yet another embodiment of the invention,

Figure 10 is a cross-section of a boat, according to the present invention.

Detailed Description

[0019] The present invention concerns Catamaran boats 10, as illustrated in the Figures 1 through 10, comprising two side hulls 11.1, 11.2 and a rigid connecting structure 12 mechanically connecting the hulls 11.1, 11.2. A passenger compartment 13 is provided between said hulls 11.1, 11.2 and the boat 10 is powered by four engines 20.1, 20.2, 30.1, and 30.2, as will be described in the following sections.

[0020] According to the present invention, the boat 10 comprises two marine engines 20.1, 20.2 (preferably two high-power marine engines) and two solar driven (low power) electrical engines 30.1, 30.2, as well as a common control system 40 for controlling these engines. One high-power marine engine and one solar driven electrical engine are positioned inside each side hull. As illustrated in Fig. 5, the two engines 20.1 and 30.1 are located inside the left-hand hull 11.1 and the two engines 20.2 and 30.2 are located inside the right-hand hull 11.2. The high-power marine engines 20.1, 20.2 are positioned closer to the stern S of the boat 10 whereas the electrical engines 30.1, 30.2 are positioned closer to the bow end B of the boat 10, as illustrated in Fig. 5.

[0021] In a preferred embodiment of the invention and as depicted on Figures 8A and 8B, all four engines 20.1, 20.2 and 30.1, 30.2 respectively are all situated towards the stern S of the boat 10, preferably in the rear third portion of the boat 10. This layout is preferred since the boat 10 is designed to glide on top/ above the surface of the water when in a high speed operation mode, and placing the engines towards the rear end facilitates this gliding.

[0022] According to the present invention, the common control system 40 is designed so that two modes of operation are offered where in a first mode of op- eration the boat 10 is powered by the two solar driven electrical engines 30.1, 30.2 only, and where in a second mode of operation the boat 10 is powered by the two marine engines 20.1, 20.2 only. [0023] In the following sections some key dimensions and ratios are defined which are essential for the proper functioning of the boat 10 at high speeds.

[0024] In order to provide a boat 10 that can be operated at high speeds, the overall length of the boat L is at least 2 times the width W (in particular the width at the water level) of the boat 10. Preferably, the length L is between 3 and 4 times the width W. In a preferred embodiment, the overall length of the boat L is between 10 and 15 m and the overall width of the boat is between 3 and 4 m.

[0025] In order to be able to offer sufficient displacement volume, the two side hulls have an aspect ratio between 0.5 < H_H/H_B < 1 (where H_H is the height of the hulls and H_B is the height of the boat). In other words, the passenger compartment has a "ducked-down" or concealed position between the hulls 11.1, 11.2. In addition, the width W_H of the hulls 11.1, 11.2 with respect to the height H_H of the hulls 11.1, 11.2 is preferably in the range between 0.4 and 1. It is to be noted that the respective measures are taken at the widest, highest and longest points of the boat 10.

[0026] The side hulls 11.1, 11.2, and in particular the bottom of the hulls, are designed so that the boat 10 starts to glide when the velocity is increased. At lower speeds the hulls 11.1, 11.2 displace the water and their cross-section is designed so that the resistance at low speeds is relatively small. Preferably, the hulls 11.1, 11.2 are designed so that the boat operates in a semi-displacement mode when operated at lower speeds. To enable the transition from the semi- displacement mode to the gliding mode, the bottoms of the hulls 11.1, 11.2 are flat to provide for the necessary lift of the boat 10. Best results have been achieved with hulls 11.1, 11.2 having staggered bottom surfaces, as illustrated in Figures 8A and 8B.

[0027] Since the boat 10 is to be operated at high speeds, the hulls 11.1, 11.2 underneath the water level are optimized from a hydrodynamical point of view whereas the part of the boat 10 that is exposed to air stream is optimized from an aerodynamical point of view.

[0028] As illustrated in Fig. 4, a high-power marine engine 20.1 is situated inside the left-hand hull 11.1 and an identical high-power marine engine 20.2 is situated inside the right-hand hull 11.2. Most preferably, combustion engines are employed as main engines 20.1, 20.2. These engines 20.1, 20.2 can be used to drive propellers 22.1, 22.2 via corresponding drive shafts 21.1, 21.2. Using these engines 20.1, 20.2 together with the drive shafts 21.1, 21.2 and propellers 22.1, 22.2 allows the boat 10 to be driven at very high speeds reaching 100 km/h and even more in the forward direction (arrow F in Fig. 5).

[0029] As mentioned, there are two auxiliary engines 30.1, 30.2 (one per hull). These engines 30.1, 30.2 are electrical engines being mechanically coupled to propellers, preferably cycloidal propellers. A cycloidal propeller is a propeller that may have a protective guard with one or more slots therethrough, which run at least approximately perpendicular to the direction of travel F of the boat 10.

[0030] Well suited is a VOITH-SCHNEIDER® propeller comprising a rotor which has a number of blades. Examples of such propellers are described in the US- Patents US 6109875 and US 7059923 B2. The entire disclosures of these US patents are hereby incorporated by reference. It is an advantage of the cycloidal propellers that they are extremely maneuverable.

[0031] One possible auxiliary engine 30.1 with cycloidal propeller is illustrated in Fig. 6. The cross-section is perpendicular with respect to the hull 11.1. There is a guide 33 or rail mounted inside the hull 11.1. This guide 33 or rail is attached to the hull 11.1. A mounting element 34 can be moved up and down by means of an actuator (such as a linear motor or the like). Preferably, this movement is parallel to a direction which is perpendicular to the surface of the water. An electric engine 36 may be connected to this mounting element 34. The engine 36 drives the propeller so that the blades 39 rotate around an axis A. [0032] In a preferred embodiment, the propeller is a cycloidal propeller with a plate 38 that carries the blades 39. The blades 39 are driven by the engine 36 via the shaft 37. When the auxiliary engine 30.1 is deployed, the engine 36 is powered by a battery or directly by the solar panel 14 so that the shaft 37 rotates together with the blades 39. The blades 39 are individually mounted so that they can be turned or tilted. Preferably, the blades 39 can be tilted around a perpendicular axis, i.e. around an axis that is essentially parallel with respect to the axis A. Depending on the tilting of the individual blades 39, the auxiliary engine 30.1 provides a thrust that can be used to drive the boat 10 in any direction. The di- rection of thrust can be adjusted by tilting the blades 39.

[0033] Instead of the cycloidal propellers, conventional propellers can be employed that can be turned for steering purposes.

[0034] In a preferred embodiment, the lower ends of the blades 39 are mounted in a bottom plate 15. When retracting the auxiliary engine 30.1 by moving it along said guide 33 or rail, the whole system disappears inside the hull 11.1 and the bottom plate 15 closed/seals the bottom of the hull. Preferably, the bottom plate 15 is designed so that it is smoothly integrated into the bottom of the hull without leaving any gap or steps for the streaming sea water to attack the retracted elements.

[0035] When the auxiliary engines 30.1 and 30.2 are to be deployed, they are moved downwards so as to protrude into the water underneath the boat 10. Dur- ing the first mode of operation where the boat 10 is powered by said two solar driven electrical engines 30.1, 30.2 only, these engines 30.1, 30.2 assume the position as shown in Fig. 6.

[0036] When the boat is operated in the second mode of operation, these en- gines 30.1, 30.2 are fully retracted. [0037] According to the present invention, the energy supply system comprises at least a solar panel 14 and a high-energy battery 16.1, 16.2 or some other kind of energy storage. The solar panel 14 can be connected to the batteries and/or engines 30.1, 30.2 so that the engines 30.1, 30.2 can be supplied with the elec- trical energy needed.

[0038] Preferably, the solar panel 14 has a surface area of about 7.5m². As batteries 16.1, 16.2, Lithium Ion batteries are well suited. These batteries 16.1, 16.2 have a weight of about 150 kg. The two electrical engines 30.1, 30.2 pref- erably have a maximum power of about 15 kW and are driven at a voltage of 250 V. The combustion engines 20.1, 20.2 have a maximum power of about 700 PS or more.

[0039] The dimension (surface area) of the solar panel 14 is so that the boat 10 can be operated out of the batteries 16.1, 16.2 (provided the batteries are fully charged) for about 2 hours at a speed of about 10 km/h. At permanent sunshine, an average velocity of about 5 km/h can be maintained using the electric drives.

[0040] In a preferred embodiment, the engines 20.1, 20.2 are equipped with a generator 50 that can be used to charge the batteries 16.1, 16.2 if no sun light is available or if the batteries need to be re-charged quickly. The batteries 16.1, 16.2 can also be charged by some other power source, for instance after the boat 10 has returned to the harbour.

[0041] The Catameran layout of the present invention has due to the cab- backward design (here the passenger cabin 13 is situated in the last third of the boat) the advantage that a large flat surface is provided where the solar panel 14 can be installed. It is advantageous to position the solar panel 14 between the hulls 11.1, 11.2 and ion front of the cabin 13, since they are mechanically pro- tected. [0042] According to the present invention, the various elements of the boat 10 are mechanically and electrically linked so that they co-operate and interact as schematically illustrated in Fig. 7.

[0043] As illustrated in Fig. 7, a generator 50, an energy storage 16.1, 16.2, and the solar panel 14 are connected to the control system 40. The generator 50 may be mechanically coupled to a shaft (not shown) of the engines 20.1, 20.2 so that the generator 50 can be used to generate electrical energy for charging the energy storage 16.1, 16.2. It is to be noted that the block diagram of Fig. 7 is a simplified scheme only. In a real implementation, the control system 40 controls switches and the like to route the current provided by the solar panel 14 directly to the battery 16.1, 16.2, for instance. On the output side, the control system 40 may be connected to the engines 20.1, 20.2 and to the auxiliary engines 30.1, 30.2, as indicated in Fig. 7.

[0044] For controlling or programming the control system 40, input means, such as a keyboard 60 or touch screen, and a joy stick 62 may be employed. Furthermore, the control system 40 may be connected to a display screen 64, for instance in order to display information to the user. The display screen 64 may for instance notify the user about the current mode of operation.

[0045] In a preferred embodiment, the control system 40 has certain security features to make sure that the boat 10 - despite the huge power provided by the marine engines 20.1, 20.2 - can be operated without endangering the passen- gers. A transition from the first mode of operation to the second mode of operation, for instance, can be made dependent on a number of criteria. Only at moderate sea or if the sea is quite, the full power can be extracted. Or only if the auxiliary engines 30.1, 30.2 are fully retracted, the marine engines 20.1, 20.2 can be caused to provide their full power. Yet another system may control the position of the roof elements 13.1 (cf. Fig. 2) covering the passenger compartment 13. If the roof 25 is fully closed, high speed racing may be possible, other- wise the available torque may be limited. Preferably a tiltable or convertible roof 25 is provided.

[0046] The first mode of operation may be used to manoeuvre the boat 10 into a harbour, for instance, or when approaching a beach. This mode can also be used in case of an emergency. The two auxiliary engines 30.1, 30.2 can be controlled by the control system 40, e.g. by using the stick 62, so that the boat 10 can be turned on the spot, for instance. In order to be able to control the boat 10 easily, the positions of the propellers of the two auxiliary engines 30.1, 30.2 and the number of revolutions of the engines 34 can be adjusted individually.

[0047] The stick 62 can be designed so that a forward movement of the stick results in a respective forward movement of the boat 10. When titling the stick 62 to one side, the boat 10 moves to the respective side. The stronger the stick 62 is tilted, the more power is provided by the auxiliary engines 30.1, 30.2. The turning of the boat 10 on the spot can be controlled by turning the stick 62 around its perpendicular axis (like the turning of a knob).

[0048] If a transition to the second mode of operation is desired, one can switch to this mode of operation by using one or more of the keys of the keyboard 60, for instance, or by pressing a dedicated button. This action causes propellers of the auxiliary engines 30.1, 30.2 to be retracted and the engines 20.1, 20.2 to be ignited. In a preferred embodiment of the invention, the two engines 20.1, 20.2 are controlled using the same control elements (e.g. the stick 62).

[0049] The batteries 16.1, 16.2 are constantly re-charged by the solar panel 14 as long as the energy provided by the solar panel 14 is not needed by any of the engines right away. When the generator 50 is turned by the engines 20.1, 20.2, the batteries 16.1, 16.2 are charged quickly.

[0050] Another embodiment of the invention is depicted in Figures 8A and 8B. The roof 25 may comprise a pillar 24 (called A-pillar) or column. This pillar 24 is a structural member of a windshield arrangement. Preferably, there are air inlets integrated into the pillar 24. Air can stream through these inlets towards the marine engines 20.1, 20.2 inside the hulls 11.1, 11.2. In Figures 8A and 8B the preferred position and orientation of the propellers 22.1, 22.2 and 39 are shown.

[0051] Another possible embodiment is illustrated in Figure 9.

[0052] The batteries 16.1, 16.2, tanks (for the fuel) and other heavy components are preferably positioned inside the hulls 11.1, 11.2 so that they are close to or below the water line in order to keep the centre of mass low.

[0053] In figure 10 a cross-section of an inventive boat 10 is shown. This figure has been prepared in order to illustrate a preferred positioning of the engines 20.2 and 30.2 inside the hull 11.2. The figure furthermore shows details of the rigid connecting structure 12 mechanically connecting the hulls 11.1, 11.2. As indicated in Figure 10, a 3-dimensional frame may serves as connecting structure 12. The frame may be composed of aluminum and/or composite materials. All essential elements are fixed to this frame. Also shown is one of the batteries 16.2 and the common control system 40.

[0054] For the construction of the hulls 11.1, 11.2 and other components of the boat 10 composite materials (such as carbon laminates) are preferred.

[0055] It will be understood that many variations could be adopted based on the specific structure hereinbefore described without departing from the scope of the invention as defined in the following claims.

Claims

1. Catamaran boat (10) comprising two side hulls (11.1, 11.2) and a rigid connecting structure (12) mechanically connecting said hulls (11.1, 11.2), where a passenger compartment (13) is provided between said hulls (11.1, 11.2), said boat (10) further comprising two combustion engines (20.1, 20.2), two solar driven electrical engines (30.1, 30.2), a solar panel (14), and a common control system (40) for controlling said engines (20.1, 20.2,

30.1, 30.2), whereby one combustion engine (20.1, 20.2) and one solar driven electrical engine (30.1, 30.2) is positioned inside each hull (11.1, 11.2), and whereby said control system (40) enables at least two modes of operation where in a first mode of operation said boat (10) is powered by said two solar driven electrical engines (30.1, 30.2) only, and where in a second mode of operation said boat (10) is powered by said two combustion engines (20.1, 20.2) only.

2. The Catamaran (10) of claim 1, characterized in that said first mode of op- eration is an emission-free mode of operation.

3. The Catamaran (10) of claim 1 or 2, characterized in that during said first mode of operation electrical energy is provided by a storage system (16.1, 16.2) which is connectable to and chargeable by a solar panel (14).

4. The Catamaran (10) of claim 1 or 2, characterized in that during said second mode of operation propellers of said solar driven electrical engines (30.1, 30.2) are retracted so as to provide for undisturbed underwater hulls (11.1, 11.2).

5. The Catamaran ( 10) of one of the preceding claims, characterized in that the solar panel (14) has a surface area chosen so that the solar panel (14) pro- vides sufficient electrical energy, if exposed to sunshine, so as to operate the Catamaran (10) at a constant minimum speed.

6. The Catamaran (10) of one of the preceding claims 1 through 4, character- ized in that the two solar driven electrical engines (30.1, 30.2) are positioned inside said hulls (11.1, 11.2) so that the Catamaran (10) can be turned on the spot.

7. The Catamaran (10) of one of the preceding claims 1 through 4, character- ized in that the two solar driven electrical engines (30.1, 30.2) comprise cyc- loidal propellers with a perpendicular axis of rotation (A).

8. The Catamaran (10) of one of the preceding claims, characterized in that the engines (20.1, 20.2, 30.1, 30.2) can be controlled by a common control sys- tern (40), preferably by using a stick (62).