This page is dedicated to the reseach of possible wireless communication systems. We will gather possible types and will analyze their pros and cons in accordance to our specifications and objectives
Data outputs from Bot to Host
Okay, here is where there will be two modes: Live Mode and Low Mode. In Live Mode, all these data will first be inputted directly in the system board, with some initial processing. It will then be transmitted to the host computer via a wireless communication module. What would appear on the host screen will be a HUD like display with a full colour video feed, will all the telemetry and sensor data. These data can be further processed to display useful information. For example, a terrain map can be derived from data collected by ultrasonic sensors.
In Low Mode, minimal data will be transmitted to the Host, reducing the power needed. Minimal data may include a low quality video feed (perhaps monochrome), position of Bot, etc. The rest of the data from sensors will be stored on board the Bot for later collection.
Data outputs from Host to Bot
The basic model will be remote controlled from the host computer. We can introduce autonomous control in later iterations of CE Bot
 Environment, Velocity & DistanceI guess this is something we barely touched on. Being a tough, data collecting rover, the mission time would probably be extended (1 hour?). However, the total displacement from the host computer may not really exceed 100m. Further distances may be needed for future versions of CE Bot. I mentioned previously that the maximum velocity of the Bot would be less than walking speed. 1 m/s would do, yes? Mobility of the Bot will factor in on which communication module we can choose. There may be possible obstacles and obstructions in between the Bot and Host, including elevated land.
Power RequirementsLets assume we choose the Ni-HM battery to power the main module. This includes the system board, the camera(s), and basic sensors. The system board on average may need around 18V @ 5 A (xheavenlyx, can you please verify the Acer? i'm using my old Compaq as reference, haha), which may require up to 8 cells of the battery (a guess).
In this light, the communication module must not consume too much power, lest it may decrease the mission time somewhat. This can be remedied by adding more batteries, but we have to factor in the weight as well.
Preliminary Analysis- The data transferred is delay-sensitive, might require a significant proportion of bandwidth, and must not be corrupted by attenuation.
- The module must have a range of 100m.
- The module must have effective signal propogation around obstacles and elevated terrain.
- There has to be a balance between battery weight and power consumption (Low Mode can be used to conserve power). TypesRF Modemhttp://www.testech-elect.com/maxstream/index.htm (distributor in Malaysia)
Comparison between 900 MHz and 2.4 GHzNeed to find balance between bandwidth, power consumption, range and BER.
Table of summary
To insure efficiency of the wireless module, we will probably fabricate a rudimentary antenna. Will need more research on this.
http://www.ac6v.com/antprojects.htm (theory and projects)
1) 2.4Ghz Vertical Collinear Antenna for 802.11 Applications - WardrivingOnline.com 2) Can with conical horn - WardrivingOnline.com 3) Omni-directional "spider omni" antenna 2.4 GHz for 802.11b (WiFi) WLAN 4) iTrike: The World's First Solar-Powered Internet Rickshaw! (practical implementation of spider-omni directional). Preliminary TestsExperiment 1: Webcam streaming over wireless lan
Experiment 2: Effect of using omnidirectional antennas to enhance signal quality
Experiment 3: Measuring power consumption of 802.11 transmissions |
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CE Bot >
Communications |
Excellent. This is really good! Now whatever tests you do post them here under. "Tests".