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Joysticks are the most suitable hand-controllers for dynamic applications such as the remote operation of a vehicle or camera tracking system. They are available in two basic forms; displacement or force sensitive: |
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Daco manufacture both types of joystick but this page is only concerned with displacement joysticks. For more information on force operated devices please see the "Design" page in the "Force operated, miniature joystick" section. The MP1 Displacement joystick range has been developed for military or demanding commercial applications that require robustness and high reliability combined with optimum accuracy and 'feel'. The use of potentiometers to sense displacement, in preference to non-contacting sensors, ensures a low component count and consequently higher MTBF figures. Potentiometers also have lower electrical emissions and are less susceptible to interference from external sources. For ultimate reliability the particular potentiometers used by Daco are IP65 sealed, conductive plastic devices that have none of the problems sometimes encountered with open track and wire-wound potentiometers. The outputs are referenced to centre taps to remove any offsets and give stability ensuring that, at zero deflection, the outputs are not affected by supply voltage. Direct coupling of the potentiometers to the gimbal mechanism totally eliminates backlash. The gimbal mechanism itself is, to the best of our knowledge, the strongest commercially available. Its components are machined from steel or aluminium and are supported by sealed stainless steel ball races mounted in a formed frame. This, in turn, is welded to a panel-mounting flange that is machined from aluminium. The use of stainless steel and anodised aluminium also provides excellent corrosion resistance. Rising from the gimbal mechanism is a hollow stainless steel central shaft that is used to mount a grip. The bore of the shaft can accommodate up to 24 wires for attachment to switches, triggers or miniature force joysticks. This facility allows a choice of many different handgrip configurations based either on Daco's MG1 modular grip or on a fully customised pattern. The hollow shaft passes through a sprung plate that acts as a return-to-centre mechanism. The design of the plate is such that the force required to operate the joystick is the same regardless of the direction of movement. For some applications it may be better to have some "bias" in the individual axes so, on custom-built hand controllers, Daco can fit a profiled plate. Similarly, if a lower return-to-centre force is required, "lighter" springs can be factory fitted. Full-scale output on standard modular joysticks is provided from the X and Y axes simultaneously by using a square 'gate'. The third, Z-axis, is operated by rotation of the grip. All axes can be operated together and all provide ±20° of movement with a return-to-centre action. When the MP1 is mounted into a panel a gaiter, manufactured from EPDM rubber, gives sealing to IP66 whilst remaining flexible over a wide temperature range. As the base for a custom built hand controller the MP1 modular joystick can be modified to have any one, or any combination, of the three axes activated. Other special variants have included put-and-stay; high and low force; detent and position sensing switch mechanisms. As with all Daco products, MP1 series joysticks are covered by a two-year warranty and are manufactured under a BS EN ISO 9001 approved quality system. |
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Daco Scientific Limited, Vulcan House, Calleva Industrial Park,Aldermaston, Berkshire, RG7 8PB, UK. |
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Industrial Joysticks :: Military Joysticks :: Trackballs :: Control Grip Manufacturer |