Two Steel Arms and a Sliding Track Simplifying the Mechanism That Lifts a Rooftop Tent

This application covers a rooftop tent for a vehicle in which the hard top is raised off the base by a pair of crossed arms rather than by a multi part lifting assembly. The applicant is Bushwakka, the adventure gear maker founded in South Africa and now operating out of Queensland, and the named inventors are the company’s founders. It is a divisional of Australian application 2025200559.

The Problem

Rooftop tents changed the shape of vehicle based camping. Sleeping on the roof rather than on the ground removes the problems of uneven terrain, insects and water running under a groundsheet, and a tent that folds into its own shell can be deployed in a couple of minutes rather than the better part of an hour.

The market splits into soft shell and hard shell designs. Soft shell tents are lighter and pack smaller, but offer less protection and take longer to set up. Hard shell tents give a rigid, insulated and aerodynamic package on the roof, which reduces drag on a long drive, and they open and close faster. That is why most of the growth in the category has gone their way.

The problem the specification identifies is what sits between the two rigid halves. A hard shell tent needs a mechanism that lifts the top away from the base, holds it at an angle, takes wind load while it is up, and pulls back down flat for transport. Many current designs use multi part lifting assemblies with a number of interacting components, and complexity in that mechanism is where the failures happen: misalignment, jamming, wear at the joints, and repairs that cost more than the convenience was worth.

There is a manufacturing angle to the same complaint. Intricate mechanisms are harder to build and assemble consistently, which raises unit cost in a category where the whole selling proposition is simplicity.

What This Invention Does

The claimed tent has a rigid base and a rigid top, both aluminium and closely matched in size so they meet as a clamshell, with flexible fabric sidewalls running between them. The top moves relative to the base between a sleeping position and a transportation position, driven by at least one moveable joint on each side.

The joint itself is the substance of the claim. It consists of just two arms, a primary arm and a secondary arm, pivotally connected to each other near their midpoints so that they cross in the manner of a pair of scissors. In the described embodiment the primary arm actually passes through a hole in the secondary arm, which keeps the pair compact and coplanar.

What makes the geometry work is that each arm is anchored differently at its two ends. One end of each arm is pivoted to a fixed hinge segment, on the top for the primary arm and on the base for the secondary arm. The other end of each arm is both pivoted and free to slide, running in a track fitted to the opposite panel on a small carriage in the form of a movable pin. Two fixed pivots and two sliding pivots are the entire kinematic description of the mechanism.

Because the arms cross, the top rises and tilts as the carriages travel along their tracks, giving a wedge shaped sleeping space rather than a parallel lift. A biasing mechanism, a spring or a hydraulic or pneumatic ram, extends between the base and the top and pushes the top away from the base, so the user is not lifting the shell unassisted. Locks between the base and the top hold the clamshell closed on the road, with the fabric sidewalls and their ventilation apertures folded inside.

Key Features

• Two arm scissor joint. The lifting mechanism reduces to a primary arm and a secondary arm pivotally connected to one another near their middles.
• Mixed fixed and sliding anchors. Each arm has one end on a fixed hinge segment and the other end on a carriage that both slides along a track and pivots, which is what converts arm rotation into a controlled lift.
• Nested arm construction. The primary arm passes through the secondary arm, and both are U shaped in cross section in steel, keeping the joint narrow while retaining stiffness.
• Assisted deployment. A spring or hydraulic or pneumatic ram between the base and the top biases the top upward so the shell does not have to be lifted by hand.
• Clamshell transport position. The base and top are of similar size and lock together with the flexible sidewalls enclosed between them, giving a low profile, low drag package on the roof.
• Ventilated fabric envelope. Nylon ripstop sidewalls with apertures run around all four sides, providing airflow and access to the sleeping area over a mattress laid on the base.

Who Is Behind It

Bushwakka began in Worcester in the Western Cape of South Africa in the late 1990s as a builder of off road camping trailers and caravans, and grew into a maker of 270 degree awnings, rooftop tents, freestanding awnings and overlanding accessories sold through distributors in Australia, New Zealand, the United States, the UAE and Europe. The South African manufacturing arm trades as Bushwakka Africa; the Australian arm, Bushwakka Adventure Gear, is based at Coomera in south east Queensland and is the entity behind this filing.

The named inventors are Johannes Hendrik Loots and Annelize Loots, the husband and wife founders of the business. Johnny Loots is the managing director of the Australian company, and the pair moved to Australia in 2018 to establish the local operation after years of building and converting vehicles for overlanding in South Africa. It is a small company filing on its own core product rather than a corporate portfolio filing, which is comparatively unusual in this batch.

The application is a divisional of Australian application 2025200559, filed the previous year. There is no foreign priority claim in the specification, so the chain begins and stays in Australia.

Why It Matters

Rooftop tents sit in the middle of a large and still expanding overlanding and four wheel drive touring market, and Australia is one of its strongest per capita markets. The category is crowded and largely undifferentiated at the fabric and shell level, which pushes competition onto the mechanism: how fast it opens, how much headroom it gives, and whether it still works after five years of corrugations.

Technically, the interest here is in subtraction rather than addition. A crossed pair of arms with two fixed pivots and two sliding pivots is a classic mechanical linkage) problem solved with the minimum number of moving parts, and the specification is explicit that fewer parts is the point. Fewer joints mean fewer places to seize, less tolerance stack up on the production line, and a load path that can be reasoned about directly. Gas struts or springs then handle the effort so the simplification does not cost the user anything at deployment.

The filing strategy reads as a working manufacturer protecting a specific product feature rather than as a defensive portfolio play. A divisional filed a year after the parent typically means the claim set is being split, most often to pursue a broader mechanism claim separately from the specific embodiment, which is what a company does when it expects the design to be copied and wants a claim that reaches beyond its own exact hardware.

Related Concepts

• Roof tent – the product category this mechanism sits inside.
• Linkage (mechanical)) – the field of study covering crossed arm joints of this kind.
• Gas spring – the biasing mechanism that assists the lift.
• Overlanding – the touring culture that drives demand for fast deploying vehicle shelter.
• Ripstop – the woven nylon used for the flexible sidewalls.
• Bushwakka Africa – the original South African manufacturing operation behind the brand.

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AU 2026202082 was published in the Australian Official Journal of Patents on 9 April 2026 and is open for public inspection. Patent applications represent inventions that are sought to be protected and do not necessarily reflect commercially available products.