next topic »

[on:]

Hello all
I have had an idea of building a robot that behaves like the Payload Cart in the game Team Fortress 2 for use in Airsoft games.
Intended use is airsoft indoor CQB fields which are usually converted warehouses. I am going to use a DFRobot 2WD platform for dev than upgrade to something like a gears HMC with the final enclosure being a Traffic Barrel. Primary Navigation will be Line Following with the track will be laid out with Spike Tape. The problem is I want it to move only when a friendly team member is within 1 meter. A wireless tagging system like rfid seems ideal for this but I am having difficulty finding a unit with a 1 meter read range.

[Reply #1 on:]

maybe you can use ultrasound for this, here's my idea:

Mike, John, and Alex must escort Robot Alpha
Bob, Kyle, and Wesker must escort Robot Bravo

Everybody has a RF transceiver and a ultrasound transceiver

First, Alpha tells Bravo "be quiet for a second" via RF
then Alpha tells Mike "prepare for ping" via RF
Mike tells Alpha "I am ready for ping" via RF
then Alpha sends out a short ultrasonic ping
when Mike hears the ping, it replies with a long ultrasonic ping
now Alpha, the robot, knows the distance to Mike by timing the pause between pings, if he is too far away, Alpha will try John.
After Alpha is done, it can tell Bravo "I am done with my team, you can start talking to your team now"

This scheme can probably be done for under $50 per player. The distance measurement can be fairly accurate, the long and short pulse will allow Alpha to know if the sound is from a player or from a near by solid object, and the RF transceiver makes sure that the robots knows exactly who they are listening to


...............


or you can try using RSSI of some RF radios, try adjusting their output power and calibrating it. I know you can read the RSSI and set output power on the Nordic radio transceivers, they can also switch frequencies and channels when you tell them to