Home and office curtains can move along a traditional wooden or metal pole, attached using rings. A more modern approach is to use an extruded aluminium track with multiple runners which bare the load of a pair of curtains. As more spaces become automated, the use of assisted or fully automated blinds and curtains is becoming prevalent. Our customer approached us with a simple brief - An automated system that could fit inside their standard 22mm track profile. This was particularly challenging since the space available to us was tiny, considering the relatively large loads required to move heavy black out curtains across spans of up to 4 metres. Another key target was for the system to work with their signature flexible track which can be moulded into bay shape windows by hand, and brackets fitted once the profile was determined. The solution had to be designed with manufacturing costs in mind, but appeal to the higher end markets, so aesthetics and design cleanliness must be considered.
After reviewing what the market already offered, a series of concept sketches were presented to the customer. These explored the possibility of using different powertrains and force mechanisms. Amongst these designs were: semi flexible lead screws, efficient DC motors, pneumatics, rack and pinion systems, and capstan drives. After reviews with the customer and other designers, a capstand drive proved to be the most effective. The ability for a single module to travel along a straight or curved track, whilst not inflicting abrasion on tension belt systems on the curved track interior was a big advantage. It also benefited from having a very simple setup. For a concept control, a small brushed micro-robotics motor was joined to a driver and ESP32 running MicroPython. The micro controller connected to a webserver over Wifi which displayed simple user controls such as direction control and speed. At this stage, limit stops were not implemented
At the end of the concept project stage, the proof of concept did its job of ironing out uncertainties in the design and paved the way for further refinement. The capstan drive was effective at pulling a small load along the length of a small curved rail. In the future, the drive will be refined further to include bearing supports and a low friction contact surface, as well as determining the wiring management and electrical power delivery techniques.
"Proving out the first steps in a project like this was rewarding, especially as we found a path forward with some significant spatial challenges and the requirement to build the new system into existing hardware"
From the project
Published with the express consent of both parties. The buyer chose to remain unnamed, so they are described by sector only. All quotes are unedited extracts from verified reviews.
