Beyond Hydraulics

Posted October 20, 2009

by Community Admin1

When Mike Turner was asked to look at emerging technologies in the world of big wheel loaders, with a view to replacing hydraulics with alternative methods of actuating dig mechanisms and propulsion systems, he was quick to act. Find out more in this article from Experience Manufacturing.

The director of industrial design company, Mike Turner Design Ltd, spent five and-a-half years as a senior designer at JCB, although this latest project would be even more challenging, as he needed to transform a futuristic technology into a cohesive concept in just one week.

Mike Turner Design decided on an approach based on the use of Electro Active Polymers (EAPs). The technology, which is currently being worked on by NASA teams in Pasadena, California, effectively relies on ‘plastic muscles’. These act like naturally occurring tissues in an arm or leg, and bend or contract as a response to small amounts of electricity.

“Such solutions might seem off the wall or avant-garde now but might conceivably be up and running within the next ten to fifteen years,” says Mike. “I didn’t think it would be a massive leap of logic to assume that if the technology keeps moving forward that within this kind of timeframe, EAP arrays could be used to power digging machines rather than hydraulics.

“The basic configuration, the linkages and the way it would perform needed to be along the lines of a typical current machine. However, there would, of course, be no need for hydraulic rams, all the technology would need to be embedded into the dig arms themselves.”

Mike began to transform his ideas into 3D models using Autodesk Alias Design, to manage the 3D surface data, and Autodesk Showcase, to communicate form and to present multiple design variations.

“Rather than making it look like an animated creation from the latest blockbuster science fiction film, I wanted to keep the look of the machine believable and realistic – rooted in the realities of existing machine design,” he adds.

The Transformation

“There was very little 2D sketching involved,” says Mike. “It’s the workflow I’ve developed in industry and during my time with JCB. I don’t really spend a lot of time sketching, usually you’re working with an engineering package where you have the basic constraints laid out and the bare bones of an idea, so what I’m normally doing is working over the top of that.

“It’s more constraints-driven than anything else: you’re trying to make shapes fit around where the engine needs to be, where this and that need to be. What I tend to do is start block modelling in Alias almost straight away to get the basic bones down of the 3D design to understand the proportions of it properly. Then maybe I’ll take screen grabs from that and ‘fag-packet’ doodle over the top of it, but a lot of the time I’m just designing it in CAD as I go.”

“I used Alias Design to develop a preliminary computer aided industrial design model that both defined the design and packaged the principal elements.”

“Alias gives you more direct control over the surface you are working on when you are NURBS modelling than any other engineering design software that I have worked with,” opines Mike. “You can play with the model and adjust it until it matches the precise way you want it to look.

Mike adds that the other key benefit is that you can import image planes and work directly over the top of them. “It is easy to retain the character of your original sketch and build on this as required.

“It feels a logical extension of physical model-making and follows exactly the same techniques and conventions. As a design tool, it understands what designers do and how they work. As a modelling package for industrial design work, I don’t think there is anything to touch it.”

Visualisation and Rendering

Showcase was used for the later stages of livery development work and the final stages of looking at different variants of the design to tweak and refine. Turner was left impressed by the power of the tool. “The quality of presentation material you can generate and the way you can go into the system and change colours and swap liveries live, quickly and easily, or set up animations, turntables and fly-bys is excellent,” he says. “It helps to give you confidence in the look of the final design.

“Rather than just focusing on a static image, you can go in and explore details, pan-around geometries and answer pretty much any questions that the client has got,” he continues. “It is invaluable for putting digital data in a context that non CAD-based people can easily digest.”

The monetary benefit of such technology is also a welcome to the Derby-based designer. “The cost of producing a large-scale mock-up for design sign-off can be prohibitively expensive. Using Showcase allows you to do more with less and helps reduce the money you spend on prototyping.”

He explains that because this was not a live project and there was never an intention to take it into live commercial production, it is difficult to put a precise figure against the time and cost savings achieved.

“However, on similar projects I have carried out in the past, I have always found the costs of producing full size computer numeric control (CNC) styling sign-off models for machines of this scale to be prohibitively expensive,” he adds. “It can cost upwards of £60,000 for the numerous CNC machined parts required to build a full sized, fully detailed exterior mock-up alone.

“If it was a live job, there would also be a large time penalty incurred when producing a physical mock-up,” he says. “From the point at which surfaces are considered to be finalised and suitable for review, there is typically a two to three week turnaround time, at least, to get all the prototype components tooled, moulded, prepped, painted and delivered on site.

Realistically, you can expect to add a further week to get everything accurately assembled and fine-tuned prior to review. As such, time-wise the project typically has to wait a month from data release through to review date; which is down-time as far as ‘productionising’ the design is concerned.”

For these reasons Mike Turner Design is a strong advocate for using Showcase in styling reviews. “The obvious time-savings associated with being able to obtain instantaneous feedback from this kind of design are desirable for any project team, as it allows them to maintain their momentum on the job. While Showcase doesn’t negate the need for fully representative pre-production prototypes downstream, it can make a significant difference to the upstream costs and time investment traditionally associated with obtaining styling approval.”

Maya was used for the final renderings, with the key benefit being the transfer of data files from Showcase. Mike explains that there was no need for any costly or time-consuming re-modelling and that the final images were faithful to the original data. This was key to the design process that had a time-scale of only one week. 

ANTARES comes of age

The resulting digger design is the first in a series of similar projects under the brand name ANTARES (named after a red supergiant star in the Milky Way galaxy) that Turner is planning over the coming months.

“ANTARES is a kind of catch-all term which covers all of the developments on which I am currently focusing,” Mike says. “There is a kind of continuity, so other projects that I carry out in the future around this basic concept will also be branded ANTARES and will have a similar kind of corporate identity, signature and form language.

How ANTARES ultimately develops is still reliant on the future development of EAP technology, although Mike Turner will continue to envision the future of heavy machinery through Alias and Showcase.

www.miketurnerdesign.com 

What are Electro Active Polymers (EAPs)?

EAPs are essentially ‘plastic muscles’ that act like naturally occurring tissues in an arm or leg and bend or contract as a response to small amounts of electricity

EAPs have attracted attention from engineers and scientists from many backgrounds. A great deal of research has been done in the field of biomimetics, where robotic mechanisms are based on biological models with the aim to mimic the movements of limbs or even an entire creature.

Currently the technology is limited by several factors. Low actuation forces, mechanical energy density and lack of robustness mean that in their present state EAPs would be unsuitable for heavy engineering. However, this technology is expected to advance, especially in size, with developments already showing successes including miniature manipulators, miniature robotic arms and grippers.

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