Lost heat is also expensive, so government authorities and businesses need to manage heat efficiency for commercial benefit. The most effective approach to monitoring is through a heat map, generated by satellite imagery. However, up to now, this option hasn’t been widely available but that is set to change with the launch of Hibiscus.
Scheduled to be sent into orbit at the close of 2026 via a SpaceX rocket, Hibiscus is a new type of thermal imaging satellite that will bring down the cost of thermal imaging, opening the benefits of ultra-high resolution heat mapping to a wide range of applications. This could range from agricultural uses, where thermal pictures can assess irrigation performance, to security cases with heat mapping of vehicles, to sustainability planning with urban energy use monitoring. Equipped with a high-resolution camera, Hibiscus will capture thermal images accurate to +/- half a degree centigrade, with area precision down to the size of a car.
Commercial Advantages of Hibiscus Satellite Design
A key commercial advantage of Hibiscus, which is being developed by Super-Sharp Space Systems, a team originating out of the University of Cambridge, is its low size and weight, combined with a folding design. Launch cost is a significant factor, where Hibiscus will share the footprint of the SpaceX rocket with other satellites. However, Hibiscus’ innovative design will occupy a much smaller volume compared to existing thermal imaging satellites in transit. This will result in a significantly lower manufacturing and launch cost, making satellite thermal imagery commercially viable for a much larger market.
“With our telescopes, you will be able to get four times better resolution per unit cost, meaning that you can match the current state-of-the-art in thermal imaging from space using a satellite the size of a microwave,” explains Marco Gomez-Jenkins, CEO, SuperSharp. “If our clients need higher image resolution further still, we can scale up to a larger platform with a larger version of our telescope to capture the sharpest thermal images available in the market.”
How the Hibiscus Satellite Works
Onboard feedback gives automated position control Essential to the capability of Hibiscus is the nanometre-precision control of its mirrors, responsible for reflecting light from the target location towards the telescope’s sensors. This is combined with an onboard metrology system that measures the light, creating a feedback loop that automates alignment of the mirrors.
“When you're operating in low Earth orbit, there are a lot of changes in the environment because of thermal cycling. The feedback loop involving the onboard metrology system will enable Hibiscus to automatically update position every 10 seconds to enable the capture of extremely sharp images,” says Marco. “That’s a huge advantage because you don’t need to rely on manual operation of the telescope, 24/7, to update the desired position of the mirrors.”
The Deployment System and Its Performance
Hibiscus is so called because of its five, unfolding mirror ‘petals’, named after the flower with the same variation. The deployment of mirror ‘petals’ is fundamental to telescope’s ability to capture thermal images. Aware of maxon’s partnership in various space and satellite applications, notably NASA’s Mars rover programme, SuperSharp engaged the motor specialist to develop a drive system fit for the demands.
A Drive System for a Space Environment
Once the telescope satellite has been set into orbit, two maxon DCX motors, in combination with a GPX high efficiency gearbox and extended temperature encoder, will drive the deployment system of each petal. A further four DCX motors will also control robotic arms assisting with the fine adjustment of the mirror configuration.
Initially, the drive system must survive the extreme vibrations of launch. Then, once deployed in space, the motors must operate in a vacuum - and face the extremes of low temperature operation. To achieve this, the design and materials of the motor have been developed and tested to withstand the highest shock and vibration.
In space, motor lubrication also needs special consideration to prevent outgassing, the release of volatile substances trapped within lubrication when exposed to a vacuum. As well as degrading the long-term performance of the drive system, outgassing can also cause condensation that can damage wider components, so maxon has specified a vacuum-compatible grease. High solar radiation can also damage the standard PVC insulation to the motor and encoder, so a PTFE replacement, featuring higher radiation compatibility, has been used.
Performance in Space
“One of the main drivers for us in motor choice was operation in harsh environments - specifically the space environment, so seeing that these motors had heritage in other space projects was a huge plus for us,” explains Marco.
Considering the working points required for the space environment, the drive system also requires careful sizing. In a vacuum, the convection heat path is lost, and the only means of heat dissipation is via conduction. To ensure long-term operation without overheating, the drive system is oversized compared to terrestrial atmospheric conditions, yet the motor must still optimise the high torque density and low mass profile required to compliment Hibiscus’ compact footprint. Crucial to achieve the performance the deployment system requires, the DCX motors also ensure smooth control thanks to features such as the ironless core that removes cogging.
New Possibilities in Thermal Imaging from Space
Before Hibiscus can launch, multiple prototypes continue to undergo rigorous testing to de-risk the technical elements. However, as the technology of thermal imaging satellites is still an emerging field, not yet economically viable for most organisations, education of its advantages is ongoing.
“Thermal imaging from space is still something very new,” says Marco. “Not many organisations are aware what can be achieved, so we’re continuing to push the advantages of cost-effective, precise analysis of heat maps, for the benefit of a wide variety of applications.”
When Hibiscus is set into orbit at the end of next year, the result will be the world’s first closed loop, unfolding thermal telescope, bringing thermal imaging satellite technology to new heights.
