##  Statement of Work for Purchase Request Number RCF.1217

## 

## 

##  NASA Langley Research Center requires a new control system for its exisiting loadframe dedicated to materials tesing and research.

## 

##  A digital controller that would replace the existing Model 458 controller shall provide capabilities or features for the major system components as descibed below: 

## 

### 1) A load frame chassis of the system shall provide: 

###  -digital servo control, function generation, data acquisition, hydraulic control, 

######  and digital I/O

###### - Data acquisition reslution and rate of 16 bit and 6 kHz, repectively

###### - Function generation by 32 bit processor, standard haversine, square, and 

######  ramp waveforms and downloaded wave shapes

###### - Computer controlled transducer limits

###### - 8 uncommitted channels of digital I/O (4 in, 4 out)

###### - Slots for up to 5 conditioning modules

###### - Automated dynamic control mode switching between any connected 

######  transducer. Any connected transducer or calculation can be selected for 

######  control (typically load, strain or displacement) including load limited 

######  displacement during specimen loading

###### - 2 Computer-selectable channels of 16 bit resolution analog output for easy access to transducer signals and other critical parameters

###### - Cables for hydraulic control, servovalves, conditioners, and communications 

######  to personal computer

### 

### 2) A remote station control panel of the system shall provide: 

###### - Local actuator and hydraulic control at the load unit for ease of specimen 

######  loading

###### - A display for test specific information

###### - 4 application defined function keys for test specific control

###### - Control of hydraulic pressure

###### - Actuator positioning controller to move actuator during specimen loading and 

######  removal

###### - Load limited displacement available as a control mode for safe 

######  specimen loading

###### - Test control buttons to stop, start, hold, and resume tests from 

######  the load unit

###### - LED indication of interlocks with reset button

###### - Easy to see LED indication of switch status

### 

### 

### 

### 3) A universal conditioner of the system shall provide: 

### 

###### - transducer conditioning for AC or DC transducers

######  Normalized with an on board reference for easy portability of 

######  calibrations

###### - Low noise, low drift, high accuracy signal conditioning

###### - Computer control of range, transducer zero, excitation, filter

###### - Traceable calibration for each range

###### - Shunt calibration for 100% range

###### - Supports strain gage bridge completion.

###### - Excitation loss detection

###### - Computer controlled limit detection

###### 

### 4) A two stage valve driver shall provide: 

### 

###### - Servovalve drive signal for 2-stage servovalves

###### - Single or dual MTS Model 252 style servovalves

###### - Computer controlled dither amplitude and frequency

###### - Digitally controlled fault protection logic

###### - 16 bit resolution on valve D/A

### 

## 5) A system control software package shall provide:

##  

###### - A software interface for configuring the controller and the user interface to the test 

######  station. The user can enter and save user preferences (units, valve adjustments, loop 

######  tuning) for recall at any time

###### - A two channel on-line data display (X vs. Y or Time vs. YY), digital displays, and a 

######  function generator for setting up tuning parameters and warming up the system prior 

######  to testing

###### - An easy program for simple monotonic and cyclic test execution including data 

######  acquisition. Test data may be stored in your choice of ASCII, Lotus, or Excel formats 

######  for analysis with your favorite tools

###### - Peak Valley Control (PVC)

###### - Ability to correct for peaks and mean levels in cyclic waveforms. PVC is our most 

######  popular and widely used compensation tool

######  

## 6) Other items to be provided shall include:

### - Floor mounting for remote station control panel 

### - Remote emergency stopl cable, 10ft / 3m 

### - Ground cable, 25ft / 7.5m 

### - Load/Torque cell cable adapter, PT to MS connector 

### - Exensometer cable adapter, PT to amphenol connector 

> \- RSC / E-stop cable, 25ft / 7.5m
>
> \- Three day installation and user training at NASA LaRC