loggers

Logger Update

3/30/12

All of the electronic interconnects that glue together the various components inside the logger box are now consolidated on a single printed circuit board. This should simplify ongoing maintenance and make it much simpler to produce additional loggers.

As an experiment, a diode and bleed resistor have been added to the battery charging port, which may help prevent galvanic corrosion at its terminals, which will almost certainly be exposed to some seawater.

Inflator Kite Test

2/21/12

We tested the inflator on a kite in the shop on Friday. The overall performance of the pump, pressure release valve, and radio link exceed our requirements. The firmware crashed after several hours of operation, however, so we will need to fix this bug and ensure that any future errors do not result in a deflated or exploded kite. The test showed that the inflation rate is 1.4 psi/hour and deflation rate is 5.6 psi/hour with a 40 sqm kite in the pressure range of interest. This is fast enough to handle small leaks, temperature-related pressure changes, and minor inflation adjustments for performance optimization.

KAICam App Update

2/3/12

Jamie has made several changes to the KAICam Android application, in support of the cruise with MBARI this week. To make the screen space on larger tablets more usable, the layout is now dynamically adjusted to maximize the preview image size.

To help in situations in which the network topology changes frequently, the app now automatically find other instances of itself that inhabit the same network. This way, the remote viewing client can connect to a camera server without being specially configured with the camera’s IP address in advance.

Other improvements include better networking efficiency and stability, and the continuous logging of GPS and air pressure (for altitude) where available.

The two images are screenshots of the app running on […more]

Logger Web Interface

1/6/12

We have made progress in creating a usable web interface to the kiteboat and Kite Assist logging systems. The basic idea is that the logger acts as a wireless router and web server. Any wifi-enabled device with a browser can connect to view the logger status, monitor the realtime data stream, and to send control commands to the device network.

Pictured are two Android mobile devices, which are connected to the kiteboat logger and showing realtime telemetry. The phone on the left is displaying the boat speed, line load, and kite inflation pressure. The larger tablet has a “kite” screen selected, which shows the current kite inflation pressure, the target inflation (with +/- pressure adjustment controls), and the battery voltage […more]

K2 tow test – Dec 14

12/14/11

We tow-tested K2 today to show Jim Antrim, a naval architect and our newest consultant, around the platform. We towed out to Treasure Island and inflated the 30 sqm high aspect ratio kite to demonstrate how the mast worked. Jamie rode on K2 for the first time, in order to operate his new logging equipment.

K2 tow test – Nov 22

11/22/11

Today we towed K2 around the bay to test new logger updates. We hoped also to try our new 50 sqm high-aspect-ratio kite, but the wind was too low. Damon’s father-in-law joined us on the Protector. Joe and Vincent also tried out brand-new drysuits, and Gabe’s father visited the shop.

from Jamie:
For the first time on K2, we are now recording the kitearm angle and the rudder pitch angle. We are particularly interested in relating the rudder pitch to the boat speed, since this is an important manual adjustment that could be automated in the future. Currently, the helmsman must adjust the pitch of the rudder to keep the boat level as the boat speed changes. An example […more]

Logger as WiFi Access Point

5/4/11

The box that we use for logging boat tests contains a very small linux PC that connects to sensors, records data, and manages data displays. Connecting to it remotely from our phones and laptops to verify that it is operating correctly, to control its operation, and to have a rich real time display of all recorded data is an advantage. To this end, it now functions as a wireless access point, which was not possible on the original hardware using readily-available linux builds. Now that this is working, we can connect via any wireless device and be directed to a web page hosted on the logger.