SPS-2000

SPS-2000 Precision Positioners

Cost-Effective, High-Performance Positioning Systems

All Positioners manufactured by Cobham are based upon the same scaleable design that is the result of more than 20 years experience of Positioner design, development, manufacture and support. The SPS-2000 is Cobham's mid-range Precision Positioner. Weighing less than 180 lbs, it is designed to rapidly and accurately position payloads weighing up to 400 lbs, to an accuracy of 0.005 degrees. The SPS-2000 is a Commercial-Off-The-Shelf COTS solution suitable for airborne, shipboard, vehicle-mounted or land-based applications, including surveillance, tracking and fire control.

Designed to meet the growing demand for cost-effective, highly accurate positioning of long-range, high-performance sensors, the SPS-2000 combines an excellent payload-to-weight ratio, accuracy, stiffness and speed with a useful life of twenty years, during which minimal maintenance will be required.

The modular design of the SPS-2000 Series allows customization of virtually all Positioner and control parameters to meet the needs of individual customers, including T-bar, yoke or 3-axis configurations. Line-Of-Sight (LOS) stabilization is achieved by the addition of electromechanical or optical rate gyroscopes and absolute positioning is achieved by use of Inertial Navigation Units (INUs).

The combination of adaptability, low weight, brushless motors and high-accuracy resolvers, with digital-servo technology, makes the SPS-2000 Series Positioners the most advanced, reliable, cost-effective, precision-positioning systems available.

Featurers

1. Easily adapted to T-bar, yoke or 3-axis configurations.
2. Intelligent user-interface for easy setup and optimization whenever payloads are changed.
3. Unmatched positional resolution.
4. Brushless, direct-drive, permanent-magnet motors for high reliability, and high performance.
5. High-speed microprocessor control and C-based firmware for fast response, ease of use and flexibility.
6. Analog or digital control via an IBM-compatible PC and/or a System Digital Control Unit (SDC).
7. Positioner weighs 160-180 lbs.
8. Benefit from Atlantic's proven experience in electronic imaging, signal processing, control systems and system integration.

Superior Adaptability

Traditionally, whatever the positioning device, significant and expensive re-design was required to meet specific customer needs, and further re-design was necessary whenever the payload was changed. The SPS-2000 Series Precision Positioners solve this problem by employing a modular design that allows the same pedestal base to be re-configured to provide T-Bar (Post), Yoke, and 3-axis configurations. Each of these configurations is also available as a rotator or with an offset elevation-axis.

By employing state-of-the-art firmware and adaptive digital control, the Positioner's performance can be optimized to a variety of payloads without re-design.

These features make the SPS-2000 Series Precision Positioners the ideal choice whenever payloads have to be changed or reconfigured.

The modularity built-in to Cobham's Positioning Systems allows components to be "mixed and matched", thereby allowing the performance and cost of the positioning system to be matched to the needs of the application. This eliminates excessive non-recurring engineering (NRE) costs and allows a highly customizable device to be maintained under a COTS philosophy.

All these features reduce cost and time-to-delivery and, consequently, improve the user's competitive position.

High Reliability

Positioners are typically located in remote, difficult-to-access locations such as building roofs, ship masts, etc. Consequently, the SPS-2000 Series has been designed to minimize the need for maintenance.

The SPS-2000 Series uses permanent-magnet, gearless, brushless, motors. These small, lightweight motors eliminate the problems of backlash, brush monitoring, pitting, arc noise and brush replacement associated with traditional motors.

The Positioner incorporates various protective measures that greatly reduce the likelihood of damage to the drive motors under conditions of:

1. overtemperature
2. overvoltage
3. overspeed
4. short-ciSDCit
5. lightning strike
6. motor operation when stowed

All Cobham Positioners are constructed of cast aluminum with stainless-steel hardware and have been designed so that they should not require repair or replacement before the expected life of the payload has been exceeded.

All SPS-2000 Series Precision Positioners are environmentally qualified for any shipboard or land-based application.

Maintenance

The SPS-2000 Series Precision Positioners have a useful life of twenty years, during which minimal maintenance will be required. They offer exceptional performance and significant cost savings, especially when maintenance costs are included.

The SPS-2000 Series is designed to make diagnosing and correction of failures as simple as possible. Most problems will be detected by the inbuilt diagnostics. These diagnostics can detect faults down to the field-replaceable unit level. As a result, the Mean-Time-To-Repair (MTTR) for the system will be very low, and training and logistics support simple and, therefore, low cost. As a result of these features, down-time will be dramatically reduced, a crucial factor especially for mission-critical applications.

Positional Accuracy

One of the most outstanding features of the SPS-2000 Series is its accuracy. Payloads can be rapidly positioned to within 0.005 degrees. This accuracy is achieved by use of multi-speed resolvers that provide unmatched positional resolution and rugged, noise-immune operation.

The low-torque-ripple motors and the inherently stiff mechanical design provide superior stability, making the pedestal ideally suited for positioning long focal-length imaging sensors.

The Positioner's Control Unit can provide automatic error cancellation. This is done by measuring the positional error throughout the pedestal's rotation (once-around-error) and introducing a correction signal during operation.

These features ensure that payloads will always be accurately positioned.

High Payload, Low Weight

The Pedestal itself weighs between 160 and 180 lbs. depending on configuration, and is capable of rapidly and accurately positioning payloads of up to 400 lbs.

The combination of payload-to-weight ratio and small size makes the SPS-2000 Series ideal for applications where space and weight are limited.

Integrated Solutions

Our proven experience in the areas of remote sensing, imaging, laser systems, signal processing, control systems, software development and systems integration makes Atlantic the ideal choice for the provision of turn-key systems and system integration.

Adaptable Control Configuration

The SPS-2000 Series Precision Positioners offer unparalleled control flexibility. The pedestal can be controlled by:

1. Cobham's own System Digital Control Units (SDC).
2. IBM compatible PC or host computer;
3. Autotracker with joystick and video monitor; or
4. Custom-built control systems.

Optional functions such as error correction, coordinate conversion, scan modes, test programs, etc., can also be incorporated.

Controlled by System Digital Control Unit (SPS-2800)

The System Digital Control Unit uses a VME bus and C-based Software/Firmware to provide control. It uses menu-driven instructions to allow novice users to quickly setup and optimize the servo response of the system to match different payloads, without the need for vendor support.

The System Digital Control Unit is available in a 19" EIA rack-mount and is available in both Basic and Full-Function configurations.

The Basic SDC is a low-cost option that allows the Positioner to be controlled manually by context-sensitive switches and/or joystick. It allows for the inclusion of IRIG data, video annotation and additional VME cards to further enhance the functionality of the system.

In addition to the above features, the Full-Function SDC has an interactive, electroluminescent, touch-screen display panel. This panel allows more information to be displayed with better visibility and consequently offers greater flexibility and functionality.

Both versions of the SDC allow the Positioner to be controlled by a PC or other host computer. This allows, for example, control of multiple positioners where collection of IRIG data and sensor positional data is required. Additionally it permits both remote and centralized testing and operation of the positioner.

Controlled Directly by a PC or Host Computer

A PC or Host computer can also be used to control the Positioner. The control software can be written by the user or supplied by Cobham.

The extra processing power available in a PC or host computer offers the following advantages:

Condition of positioner and sensor can be continually monitored and controlled.

1. Images can be displayed and processed.
2. Data from position sensors can be processed.
3. The user can develop additional control functions.
4. Project-specific, test and setup programs can be down-loaded via parallel and/or RS422/232 protocols.

Controlled by Autotracker with Joystick and Video Monitor

In addition to the above options, the positioner can be controlled by an autotracker, using a joystick and monitor for initial target acquisition, without the need for an SDC, PC or host computer.

Servo Unit (SPS-2700)

The Servo Unit is a microprocessor-based, single-board, rate-loop controller. It includes multiple RS-422 and parallel ports to allow standard connection to associated control and monitoring equipment. It drives brushless, sinewave-driven, low-torque-ripple motors with Pulse-Width-Modulated (PWM) amplifiers to provide rapid and precise control that can be easily optimized for different payloads.

In its standard version, the Servo Unit is available in a 19" EIA rack mount or rugged NEMA weatherproof enclosure for field applications; custom packaging is also available.

The Servo Unit monitors servo faults and provides a number of safety features which include an interlock to prevent remote operation of the positioner while maintenance personnel are working on the unit.

System Block Diagram

Performance

Features

The pedestal is Pre-treat primed and can be marine powder-coat painted or painted according to customer specifications. It uses all-stainless-steel hardware and is supplied with stow locks for safe transportation. A pedestal-safe switch is included to allow maintenance personnel to immobilize the pedestal during maintenance. Mechanical stops and a payload-specific electrical interface are also standard items.

Configuration

Mechanical

Environmental

Options

Power

The Positioner derives its power from the Servo Unit. Both the SDC and Servo Unit can operate from:

1. 115 VAC, single-phase, 50/60 Hz power;
2. 240 VAC, three-phase, 50/60 Hz power;
3. 24 VDC (optional).
4. Images can be displayed and processed.

 Mechanical Data (not to scale)

 All measurements in inches.

Due to Atlantic's on-going product development program, all specifications are subject to change without notice.