Marsupial News

In Perth the weather now stays hot until well into March, even April. This makes work on the Star chaser difficult, especially if it involves heat-sensitive materials such as expanding urethane foam. However as the weather changes, it becomes easier to work on the machine and progress has again picked up. The most important developments over the past month has been mounting the floor pedals, brake booster and steering column to the firewall; the finalisation of interior framework; the completion of detailed construction plans for the forward control steering linkage; the further implementation of the engine restart plan; and the commencement of the floor sandwich.

The firewall serves as an important support element for a number of vehicle subsystems, including the control console, gear levers, pedals and steering column, among others. Work fitting these has progressed well, with few holdups. Thanks to earlier wooden mock-ups of the drivers station built during the design stage, the steering column has fitted almost perfectly, and fits an average-sized person well when seated in one of the newer style seats (see photo). The steering is likely to be quite heavy, though, and may need a linear booster in the steering linkage to make the vehicle more driveable. The accelerator pedal is next. Then the seats need to be mounted on turntables so that they can be turned to face the rear of the cabin for camping.

Persistent problems with the stiffness and strength of the steering box mounting now appear to have been solved, by buttressing the steering box with a specially-designed gusset. The remaining steelwork is now done except for the interiors of the airlock doors, and the side window frames (actually Mitsubishi L300 van doors which are to be welded into place, but which have been kept off to enable easier access to the front cabin).

Another troublesome element has been the control linkages to transfer control of the gearbox forward to the cab-over-engine position. This required a special design for the Toyota engine-gearbox which is not native to the FC Landrover chassis. A great deal of detailed design work was done by MSA engineer David Willson, and the plans are now in the hands of Tony de Groot, an engineer working for Immersive Technologies, who will oversee fabrication of the linkages at their Osborne Park workshop. Mr. de Groot has also volunteered to help with the engine restart, and has specified a list of electronic and mechanical parts required to make that happen, most of which have now been obtained by the project Manager.

The floor sandwich assembly, delayed until the onset of cooler weather, has now also commenced. This involves custom-fitting sheets of 1.6mm aluminium under the body. Insulating strips are cemented to the steel frame before fitting the aluminium plates to thermally uncouple them from the frame, since they will absorb a lot of radiant heat from a desert surface or road. On top of the frame are sheets of marine plywood which forms an easy to make floor. Between the wood and the metal insulating foam is sprayed, which further insulates the cabin. The floor must be installed before the fibreglass work can commence which is the next major task.

Steering Wheel Now Mounted.

Overall view, April 2008.

Over the summer months, the pace of work on the vehicle - slowed almost to a halt over the last three months - has picked up again. The main thing holding up construction was and still is lack of workers, paid or voluntary. The project manager, Graham Mann, has been trying to find new workers in both categories. Recently three new people have committed to work on the project, and it is hoped they can help move forward on the steel frame construction and engine refurbishment. A second holdup has been a lack of construction drawings which the fabricators can use in the factory. Although detailed plans for the whole machine exist, they are AutoCAD files on computer and have needed realisation as practical construction drawings with notes for the factory workers.

Recently MSA engineer David Willson has been producing such drawings, which have already greatly aided construction on the front cabin assembly (see photo below, right). Meanwhile work on other, less visible parts of the machine, such as the exhaust system (below, left) and the vacuum reservoir for the brakes have also been added. The former MSA president, Guy Murphy, has also been working hard on the project from London, where he has been greatly improving this website and making many valuable suggestions about how more resources can be brought to bear on the project.

Customised exhaust crossover is now in place. It needs to be well clear of the gearshift top plate.

The forward cabin begins to take shape, after many delays getting suitable construction drawings to work from. The whole door structure is included in the sidewalls only for the window frame.

5 May, 2006. Efforts to accelerate the construction process have been made during March. Our strategy involves separating the construction work into several independent work packages, and have them carried out simultaneously at different sites. For example, the rover body can be separated from the vehicle chassis, so that the latter can be moved to another site for engine refurbishment work, while work continues on the body frame. A few jobs need to be finished before that can be done properly. In particular, the body mount structures needed to be completed. For the engine work the contractor ChevyPower, who gave a very competitive quote last year, has been chosen but we want them to do more than we arranged at that time, so a new deal is being negotiated. The body frame construction is currently waiting for engineer Bruce Armstrong to finish some construction drawings for fabrication. John Byfield cannot begin this work package without these drawings. Bruce says there are still some windscreen frame issues to be resolved and he needs to re-examine one of the Mitsubishi L300 doors which are to be used as side window frames. Bruce has commenced work on composite materials molding for the cabin body. Early experiments in glass-reinforced epoxy have been quite successful. Completed test articles part of an airlock door frame and a viewport frame can be seen below. Bruce is converting his workshop into a construction site for composite plastics, and we want to have a second unit working on other components at the same time.

The exhaust system needs a customised manifold connection, which looked to be too expensive to have done by on-site exhaust contractors, so we have purchased the elbows and straight components ourselves and added this to the work to be done at Byfields. They have assured me that this is relatively easy and cheap for them to do. We can easily add the rest of the system later, by simply putting on a muffler and driving it to a exhaust shop. This should save the project some money, and keep Byfields busy while they wait for the construction drawings. Some questions to do with vibrational stresses on the cast iron manifold have now been settled, so work should be able to go ahead on that task. Project Marsupial also involves other activities, which in April have included submitting a new paper to Jon Clarke’s Mars Exploration Planning II book, touring high schools (visits to Hale and St. Joseph’s school this month) and other publicity and management jobs (eg sending the Starchaser model to Luna Park's space exhibition in Sydney). Graham and Dave Cooper also attended meeting with new science staff at Trinity College with a view to resurrecting the rover-as-a-static-simulator concept, which did not go ahead last year as planned, due to problems at the Trinity end. Graham tabled an executive summary of that idea, which helps gather resources into the project, and allows me to work on as an IT-related research project. We want to make sure we keep access to the Trinity building, and have plans to develop this into a fully equipped workshop/simulation lab, which will definitely help the project. That still requires some further funding and some volunteer weekends however.

Front of rover showing bumper and radiator mount

Composite epoxy airlock doorframe fresh off a test mold

A new home for the Starchaser rover has been built by Trinity College in East Perth. The new housing is a colourbond garage with large doors, designed especially for the vehicle. The vehicle will be moved there once steelwork construction has been completed. Work currently being undertaken includes the construction of the forward bumper and the forward control linkage. It is hoped that the excellent workshop and technical facilities at Trinity College will speed up construction.

A much improved version of the 1/12 scale model was a popular eye-catcher at the recent 5th Australian Space Science Conference in Melbourne. The model joined displays of the MarsSkin 3 mechanical counterpressure suit and plans of the Mars-Oz station at the Mars Society Australia exhibit. Dozens of research scientists, students and space enthusiasts showed interest in the display and the MSA is likely to gain many new members from the event.

Workers assemble the new garage for the rover at Trinity College, East Perth.

Starchaser model on display at the MSA stand at the recent Australian Space Science Conference Melbourne.