Dynamic Measurement with GPS

This week, we plan to complete our overview of the DMS-E series of dynamic measurement products, and transition to the DMS-S series. So, we will be comparing the DMS-EGP01 GPS enabled inertial measurement sensor to our DMS-SGP01. The DMS-EGP01 combines the triaxial angular rate and acceleration data of our DMS-E604 with a single GPS antenna, which provides an integrated velocity input. This velocity input greatly enhances the unit’s performance during highly dynamic maneuvers. The integrated GPS antenna also provides velocity and track heading outputs. The DMS-SGP01 is a smaller version of the DMS-EGP01, and also offers triaxial rate and acceleration data, and has a built-in single GPS antenna. Both are primarily used for automotive testing, vehicle dynamics, and marine applications. Both operate on the same basic principles. The difference between the DMS-E and DMS-S product lines are the size, price and quality of gyros that they use. Because of this, the DMS-E series is larger in size, but offers better dynamic accuracy and less noise. Use the links to view the product specifications for the DMS-EGP01 and...

Watson Dynamic Measurement Sensor

Watson Industries’ DMS-E604 is this week’s featured dynamic measurement product. This sensor is used worldwide in applications such as vehicle dynamic testing and pipeline maintenance telemetry. An extremely accurate error correction system utilizes a forward velocity input to compensate for long-term references during maneuvers and highly dynamic conditions. The DMS-E604 offers six accelerometer outputs along with three axis of angular rate. The X, Y and Z accelerometer outputs represent the accelerations in the plane of the vehicle body while the second set of three outputs measure the acceleration aligned with an earth-level coordinate system. This sensor package provides attitude and relative heading data as well. This unit is economical, reliable and easily configurable by the user. Digital design and solid-state construction allow Watson Industries to customize this unit to your unique requirements. Output signals are available in several formats to meet our customer’s specifications. For more information on Watson’s inertial measurement sensors and other products we manufacture, contact us via email or call...

Communicating with Watson Sensors

Most Watson Industries digital sensors have settings that are saved in memory. These settings include things like data channels, and baud rate that users might find the need to change from time to time. In order to access the menu system to change these settings, the senor needs to be in Command Mode. There are a series of steps that need to be performed to put the sensor into this special mode. Connect the unit to a DC power source that is off. The viewing computer needs a valid bi-directional RS-232 serial port. Connect the serial port of the Watson sensor to the computer’s serial port. Open a terminal program (such as HyperTerminal) to interface with the unit. The default baud rate of the unit is 9600 baud. Make sure the computer’s serial port is open. Power-on the unit. A startup message will be transmitted by the unit and will appear in the terminal window unless it has been suppressed. During initialization, hit the space bar twice within close succession. Note: The sensor initialization time begins after the startup message is transmitted. Typically, this time period lasts 5 seconds, but could be as long as 127 seconds depending on your sensor. Wait until after initialization is finished. At this point, command mode will be activated and the unit will accept keyboard commands. Note: Most Watson sensors have initialization times that are shorter than 30 sec. Any extra keystrokes (other than two spacebars) sent during initialization will deactivate command mode. It can often take a few attempts to get the hang of step 5. Repeat steps 4-6 until...

Dynamic Measurement System

Watson Industries produces several Dynamic Measurement Systems (DMS) to meet the various needs of our customers. As mentioned in last week’s blog, we are continuing to highlight the different DMS units. Watson’s DMS-EGP02 is designed for applications where accurate heading is required but a magnetic compass is not feasible. The unit is equipped with triaxial angular rate and acceleration data outputs with a dual GPS antenna system that provides heading data even when the vehicle is not in motion. The addition of the antennas provides vehicle velocity data to the DMS that enhances the unit’s performance during dynamic maneuvers. The DMS-EGP02 is excellent for aerospace, land and ocean applications. Some uses include unmanned vehicles, heading reference, automotive testing, satellite tracking and surface navigation. To find more information about Watson’s inertial measurement sensors and other products we offer, contact us at...

Stabilized Pan and Tilt Platform

Last week we introduced the SPS-P230. This pan and tilt stabilized platform is unlike our previous stabilized systems because it includes an integrated user control interface. This makes the SPS-P230 a complete system, requiring no further development. Typical applications requiring this type of stabilization system include vehicle-mounted camera and antenna systems. The Joystick Controller has a joystick, four buttons, four led indicator lights and three connectors. The joystick controls the positioning of the SPS-P230 payload. The joystick itself is used to pan and tilt the payload. The indicator lights and buttons that are used to inform the operator or to control the operation of the SPS-P230 in various ways. The system allows the user to easily program a “home” position that the system will align to at the press of a button. The user can choose between two stability modes; position and inertial mode. Position mode stabilizes the load relative to its mount, while inertial mode stabilizes the load relative to its true facing. To learn more about the SPS-P230 click...

Inertial Measurement Sensors

Last week we talked about the many different inertial measurement systems that Watson Industries manufactures. Over the next few weeks, we will be highlighting each of these systems individually. This week’s feature is the DMS-EGP01. Watson Industries DMS-EGP01 offers a single antenna GPS which was initially designed to be used in the testing of drive and handling characteristics of vehicles. Applications include skid pad and crash testing. The DMS-EGP01 operates in two heading modes. The first mode uses the GPS module to calculate gyro stabilized track heading. When a GPS signal is not available, the second mode will output relative heading. This unit also has two velocity input modes. The first uses the GPS module’s ground velocity to enhance the sensor’s performance during highly dynamic maneuvers such as sharp turns. The second mode is an analog velocity input for when a GPS signal is not available. During normal operation, the DMS outputs highly accurate inertial data. Data can be transmitted using several different methods including use of the RS-232 serial output. This output includes decimal and binary...