RA47X high-speed actuator: reliable control for Caudwell Marine’s newest propulsion system
Caudwell Marine is a Cape Town-based manufacturer of high-performance racing and recreational marine engines, with a drive for pushing the boundaries of innovative engineering in everything they do. Leading the industry with award-winning technology and designs, Caudwell Marine outboards provide features and benefits that make boating more enjoyable. Their solutions offer clean technology and fuel efficiency while providing power and low maintenance needs in its compact design.
Founded in 2011 by English billionaire John Caudwell in partnership with South African entrepreneur Mike Beachy Head, Caudwell Marine (PTY) LTD was created to develop a marine propulsion system through a revolutionary design that boasted zero power loss from engine to propeller. It took over seven years of research and testing by their engineering team, but they finally reached their goal and got to a first production phase. They created an internationally patented innovative design that maximized power, durability and efficiency for the luxury leisure boating market in the 16 to 40-foot range.
Caudwell Marine launched their new propulsion system at the International Boat Builder’s Exhibition and Conference (IBEX) in Miami (Florida) in October 2007. To develop their challenging products in the large leisure marine industry, Caudwell Marine partnered with independent boat builders and established close and trusting partnerships. This has allowed them to gain a solid experience in their field and to grow steadily over the years, and has translated into a global client base for the company.
OPTIMAL ACTUATOR DESIGN FOR A MARINE APPLICATION HIGH IN DEMAND
By analyzing the expected product growth as well as expected market demands, Caudwell Marine realized that there is a growing market for more powerful outboard motors capable of providing class-leading durability, maximal torque and power to weight ratio, fuel efficiency, minimal emissions, smooth power, and safer handling. That is why they are constantly updating and improving their drive systems by reviewing their engines’ ECUs, developing modern electronics with NMEA-2000-CAN-compliant systems and steering-by-wire solutions, and redefining modern electronics for control and display purposes.
So, as more powerful outboards are needed, more demanding technical requirements have to be met. It is in this particular road map that the South African manufacturer contacted REGNER© in October 2017 to build a sturdy and reliable linear actuator, which had to provide high speed in a very short stroke intended for gear selection applications.
Caudwell’s requirements were very clear: they needed reliable electric linear actuators with analog feedback for precise positioning, and the first prototypes had to be delivered by February 2018. Therefore, REGNER© had five months to design, test and produce a very complex solution.
Specifically, the demanding actuator for marine environments had to meet the following technical specifications:
|Power supply||12 VDC|
|Max. load||1,000 N|
|Max. speed||Up to 70 mm/s|
|Stroke length||40 mm|
|Compact design||240.5 mm|
|Limit switches||At stroke end points|
On average, the development of a new linear solution takes a minimum of five months from start to the beginning of serial production (start of production, SOP). The process of designing and developing a new linear actuator requires research, finding certified high performance materials, and assuring compliance with safety standards.
In this case, we worked virtually, yet closely, with the engineers of Caudwell Marine by defining the different standards that the actuator solution had to meet, and we established a Gantt Chart to get the project under control with its relevant milestones.
After making sure everyone understood all the requirements, we performed several calculations to define the appropriate permanent magnetic motor. Once the motor was chosen and tested, we designed the different components and their connections. We integrated controls, wiring, PCB transmission, and other technical parts. Once that was done, we assembled some units, checked tolerance, and performed tests on functionality, load, temperature, EMCs, and fatigue.
“I must inform you that myself and the team are very excited regarding the final solution you are providing. We are very impressed”
Jean Pierre Jacobs
Drive-train Manager at Caudwell Marine
EXCEEDING CUSTOMER EXPECTATIONS
Tests show defects or possible improvements that lead to further optimization of the design. In the case of the project for Caudwell Marine, rigorous testing lead to the modification of the actuator’s design, and we entered into a new iteration cycle with an improved prototype that was tested again. When all the testing results were satisfactory, the final prototype took form.
For this demanding application the outcome is a very robust actuator with a high IP degree and special anodized aluminum housing, making it ideal for use in even the harshest of marine environments. The RA47X offers top quality in every detail and ensures reliable performance with a duty cycle of max. 10 % in temperatures ranging from -20 ºC to +60 ºC.
Moreover, due to its compact size, the RA47X is well suited for applications that require short linear movements.
The linear actuator during the IP65 testing