Beta 1


Title SAILOR 900 - Elevation Drive
Translated title SAILOR 900 - Elevations Drev
Author Frølund, Thyge (Copenhagen University College of Engineering, IHK)
Simonsen, Jesper (Copenhagen University College of Engineering, IHK)
Supervisor Schreiber, Mads Peter (Copenhagen University College of Engineering, IHK)
Institution Ingeniørhøjskolen i København, IHK, DK-2750 Ballerup, Denmark
Thesis level Bachelor thesis
Education Diplomingeniør, Maskiningeniør
Education Bachelor of Mechanical Engineering
Publication date 2013-05
Abstract I samarbejde med Cobham blev forskellige mekaniske problemer på deres antenne design analyseret. En af disse problemer blev udvalgt til forbedring. Udvælgelsen var baseret på områder, hvor optimering og videreudvikling var ønsket og kunne resultere i en billigere og et mere simpelt design. Det mest relevante problem for både Cobham og dette projekt var elevations drevet af parabolen.
Dette projekt har til formål at udvikle et nyt elevations drev til Cobhams SAILOR 900 antenne. Det nuværende SAILOR 900 design har en rem mellem en motor og akslen der roteres. For at sikre at remmen hele tiden holdes er stram under alle forhold, bruges en remstrammer.
Årsagen til udviklingen af det nye design skyldes primært varmeudvidelse og de ekstreme temperaturkrav af systemet. Den store temperaturforskel forårsager forskellige ekspansion af remmen og armen. Denne ændring i længden, resulterer i slør hvilket ikke er ønskeligt, derfor anvendes remstrammeren på den nuværende løsning. Remstrammeren er ikke en ønskelig løsning, og derfor bliver et nyt design udviklet. Endvidere er en højere gearing mellem motor og elevation akslen fordelagtigt. En højere gearing vil øge præcision af elevation akslen. Desuden kan en mindre motor bruges.
Forskellige løsninger på problemet er blevet undersøgt. Oprindeligt var et gear design målet, herunder overvejelse af forskellige gear materialer. Gear designet blev forkastet, og derfor var en ny løsning nødvendig. Dette resulterede i en "to remtræk" løsning. Denne løsning giver en højere gearing end den nuværende, hvilket giver en større præcision og mindre slør sammenlignet med andre designs. Det nye design er blevet undersøgt gennem beregninger og FEM analyse og viste sig at være implementerbar på antennen.
Abstract In cooperation with Cobham different mechanical concerns regarding their antenna design were reviewed. One of those concerns was selected for improvement. The selection was based on areas where optimisation and further development was highly wanted and could result in a cheaper and more precise design. The issue most relevant to both Cobham and this project was the motion drive of the satellite dish itself.
This project aims to develop a new elevation axes drive to Cobham’s SAILOR 900 antenna. The current SAILOR 900 design has a belt between a motor and the axes to be moved. To make sure that the belt is continuously tightened under all conditions, a belt tensioner is used.
The reason for the new design is primarily due to heat expansion and extreme temperature requirements of the system. The temperature range causes different expansion between the belt and the arm length. This change in length, results in back lash which is not desirable; therefor the belt tensioner is used. The belt tensioner is not a desirable solution and therefore a new design should be implemented. Furthermore is a higher gearing between the motor and the elevation drive desirable. A higher gearing will consequently led to an increased precision of the elevation axis. Furthermore, a smaller motor could be implemented.
Different solutions to the problem have been investigated. Initially a gear design was executed, including consideration of different gear materials. The gear design was rejected; hence, a new solution was necessary. This resulted in a “two belt drive” solution. This solution provides a higher gearing which causes a higher precision and lesser back lash compared to other designs. The new design was investigated through calculations and FEM analysis and was found to be implementable on the antenna.
Pages 155
Keywords VSAT Antenne Cobham ; VSAT Antenna Cobham
External partner Ledere og medarbejdere i private virksomheder
Admin Creation date: 2013-06-16    Update date: 2013-09-27    Source: ihk    ID: ihk-14897908    Original MXD