Project Torpedalo - Extreme Machine from Extreme CAD
Project Torpedalo is quite simply the most advanced pedal boat ever created and it is to be used to cross the Atlantic! Madness you say? Well two Design Engineers from Bently Motors: Mark Byass and Mike Sayer have designed and built their own pedalo and they plan to pedal 3,000 miles (naked!) in December 2011. It is important to note this is for charity (also to break the World Record), the objective is to raise £250k for Make-A-Wish Foundation and Motor Neurone Disease Association. So what has this got to do with Computer Aided Design (aka CAD)? Well you can't take this boat on a real test drive, you can't sit and pedal for 30 days just to make sure it works. So what do you do? DIGITAL PROTOTYPING
Digital Prototyping in a Real World
When people think of CAD they think of architects designing buildings or manufactures designing everyday objects but they think of these as static models without intelligence. Digital Prototyping (in architecture called BIM) is revolutionising the way the design industry is creating and building more and more advanced machines. The designers and engineers work together to create a virtual machine, in this case a pedalo.
The boat is built in a computer in 3D with every screw, nut and bolt and then tested; virtually. We are now at a stage where computers can give an object(s) intelligence. Example: your testing a bridge which you want to build to see how it will stand up against storms. Computers can simulate weather conditions and apply stresses to the virtual bridge. This bridge is programmed to react in exactly the same way as if it was built and how it will survive these stresses over time. Currently the new Oakland Bay Bridge in San Francisco (currently being built) was tested in this way. Also the Millau Viaduct in France (tallest bridge in the world) designed by UK Architects Foster and Partners was only made possible because of this amazing technology.
Back to Project Torpedalo
Mark and Mike designed their own closed-cockpit, triple compartment self-righting pedal-driven monohull (aka Pedalo) from scratch. It is 8.3m long from bow to stern, with a single pedalling position and a sleeping cabin at the back, the boat has been carefully engineered to do everything that it needs to do, and is optimised for an ocean crossing. By designing the boat themselves, they were able to focus on making the boat efficient and fast, whilst remaining stable and important ability to self-right in the event of capsize (which is likely considering 40 foot waves with 8 foot breakers). The boat also has to be their home for at least 6 weeks and carry everything that two people need to survive for that long.
Crucial CAD for a Crucial Design
The initial plans involved building large scale models of the boat and testing it in a wind tunnel. While the resources for this were secured, timing plans couldn’t be worked around the availability of the tunnel. So, instead the designers decided to use Computational Fluid Dynamics (CFD) to model the airflow over the boat in the variety of wind conditions. This modelling takes a lot of computing power and specialist software but saves time and money in creating scale models which would have to be tweaked many times before they bring the correct results. By using a powerful computer tweaks can be made quickly and efficiently on the virtual model to achieve the results needed for the project.
The drivetrain design is clearly crucial to the success of the adventure. It had to be light, efficient, easy to service, and simple. The first concept for the drivetrain featured a vertical driveshaft with a right-angle gearbox at each end, but quickly they realised that this layout would be heavy and difficult to fix if it failed without taking heavy spare gearboxes. Head of Engineering at Bentley Motors, suggested using a belt drive. Modern belts don’t stretch, are very efficient, are light, don’t need perfect alignment (unlike chains) and crucially can be twisted – meaning the direction of rotation of the drive train (from pedal to propeller) can be changed without a gearbox. Once again through CAD models and testing this could be proved, the image of the drive train is shown on the right, which is was created as a full virtual working model.
The original boat concept had a propeller at the stern, but with the amount of vertical pitching that the boat will do in rough seas they noticed that a stern prop could be lifted out of the water. For this reason, and with the pedalling position in the centre of the boat, they decided a propeller on a keel board directly under the pedaller was the best solution.
The result of over a year of design work with the help of amazing software is a fast, stable boat that cuts well through the water and the air and most importantly be able to cross the Atlantic.
Charity and the World Record
This project is a charity event like no one has ever seen! Mark and Mike have done all the design work themselves, sourcing materials, companies and professionals to help them. The boat will take part in Woodvale Challenge, a trans-Atlantic rowing race involving roughly 30 rowing boats that takes place every two years – Mark and Mike be the first crew ever to compete in a pedalo. A pairs pedalo has only ever made this journey once before, in 1994, taking 111 days. They want to do it in 38 days (most definitely possible) and if they succeed, they will set a new World Record.
I have full confidence that both Mark and Mike will succeed and I write this blog not only promote the use of Digital Prototyping and CAD but to promote them and their amazing project. If you can please donate and if you have any questions about the article please comment or contact me regarding the use of CAD for different projects.
