The most cost-effective solution to directional wave monitoring requirements in all shallow water coastal applications, The MIDAS DWR Directional Wave Recorder represents a significant advance in PUV wave recording technology.
The MIDAS DWR brings a range of unique features, as well as the standard non-directional data available from the MIDAS WTR, the MIDAS DWR performs full onboard directional data analysis, allowing real-time directional information at an unsurpassed 2° resolution.
The MIDAS DWR is fitted with a choice of strain gauge or high accuracy piezo-resistive pressure sensors, and a fast response PRT temperature sensor as standard. Note that whilst the piezo-resistive sensor offers a higher absolute accuracy, the quality of wave data owes more to deployment location and sampling pattern than to sensor performance. Optional additional sensors include Conductivity and Turbidity.
Pressure (high accuracy)
100dbar (90m water)
50 dbar (40m water)
-5 - +35°C
0 – 360°
2 Axis EM
0 – 80 mS/cm
0 – 2000 FTU
In order to correctly measure wave activity, Linear Wave Theory requires a specific number of data points to be sampled over a period of time. These data points are then processed on board the instrument to generate an accurate summary of the wave activity during the measured period. The MIDAS DWR therefore operates in a strict pattern of “sample, process, sleep”, with the user controlling the number of samples and the sampling rate, together with the duration of the sleep period. This may be minimised for almost continuous sampling, but obviously at the expense of battery and memory usage.
Minimum cycle time is nearest whole number of minutes after processing has finished.
Instrument can be programmed to begin sampling at a specific time.
Wave Sampling only occurs if pressure activity exceeds a defined level.
The MIDAS DWR is fitted with 64Mb solid state non-volatile FLASH memory. Total capacity depends on setup. User may save any or all of the following: · Raw sensor data from each burst · Summary statistics of wave burst · Tide & additional sensor data · Spectral analysis of wave burst. If all data is saved, memory will typically record over 4000 data bursts. Sampling once every 2 hours, this is over 2 months data.
System is supplied with WaveLog Express PC software, for instrument setup, data extraction and display. WaveLog Express is licence free.
The instrument will operate autonomously, with setup and data extraction performed by direct communications with PC before and after deployment. It also operates in real time, with a choice of communication protocols for a variety of cable lengths, all fitted as standard and selected by pin choice on the output connector:
RS232 - Up to 200m cable, direct to serial port via USB adapter RS485 - Up to 1000m cable, addressable half duplex comms
2 wire power & comms up to 6000m cable
Baud Rate: 2400 - 115200 (FSK fixed at 38400, USB 460800) Protocol: 8 data bits, 1 stop bit, No parity, No flow control
One of the most versatile yet easy to use pressure-based wave recorders available, the MIDAS WTR Wave and Tide Recorder offers fast data upload, a quick change battery carousel and intuitive operating software.
The miniIPS is a precision underwater pressure sensor; 0.01% accuracy, a titanium housing and a choice of pressure ranges make it a cost-effective solution for offshore engineers, vehicle pilots and other operators who require highly accurate depth information in real-time.