M-TEK designs and produces Dual Axis Positioners (DAP), based on three different technologies, namely:
- Direct Drive
- Harmonic Drive®
The technology selected will depend on the application, size of the load, acceleration and maximum velocity, angular tell-back accuracy, stabilisation required, environmental conditions, cost and other factors. For all the DAP’s, slip ring assemblies, brakes, parking latches, etc can be implemented.
Angular feedback is mainly accomplished with integrated absolute resolvers or optical encoders with tell-back accuracy of up to 0.1 mRad, if required. For controlling the DAP’s, a range of Servo Amplifier Units (SAU) are used, with peak voltages ranging from 28 VDC to 200 VDC and currents up to 80 A. Control of the SAU’s are via various serial busses including RS232, RS422 and others.
Direct Drive DAP
For Direct Drive DAP’s, brushless DC torque motors are structurally coupled to the load as effectively possible, in order to produce a system with maximum stiffness (very low to zero backlash) and high torsional and acceleration response capability. Typical applications include sea based, stabilised, radar/electro-optical tracking systems. Direct Drive DAP’s with peak torques ranging from 20 Nm to 1000 Nm have been produced.
Harmonic Drive® DAP
Harmonic Drive® DAP’s produces high peak torques with low maximum current, and very low backlash. A Harmonic Drive® speed reducer, with ratios of 50:1, 80:1 and higher, is coupled to a brushless DC torque motors, in order to produce high torque. Typical applications include land based, radar/electro-optical tracking systems, electro-optical observation systems, test systems, etc. Harmonic Drive® DAP’s with peak torques ranging from 30 Nm to 600 Nm have been produced.
Geared DAP’s produces high peak torques with low maximum current, which is achieved with the implementation of a slew gear/planetary gear box or worm gear combination, with typical gear ratios of 60:1 or higher. Backlash will be evident in these positioners. Typical applications include positioning of large and small dish, tracking antennas susceptible to high wind loads, with a relatively low angular accuracy requirement. Geared DAP’s with peak torque ranging from 5Nm to 300 Nm have been produced.