FTC Tips
Tips for connecting NXT to RobotC
- NXT can only hold seven contacts, so if you have trouble connecting check the contacts
- If you can not connect to the NXT, try pulling out the Bluetooth dongle and putting it back in
- Try to forcing it to connect in RobotC by selecting "Robot" and then "Test Communication Link"
- Restart RobotC
- Restart the NXT
- Restart the computer
- Lastly, try "Dowloading Firmware" in RobotC under "Robot"
- If you can not connect to the NXT, try pulling out the Bluetooth dongle and putting it back in
- Try to forcing it to connect in RobotC by selecting "Robot" and then "Test Communication Link"
- Restart RobotC
- Restart the NXT
- Restart the computer
- Lastly, try "Dowloading Firmware" in RobotC under "Robot"
Tips for working with Tetrix Chain and Sprockets-
Breaking and rejoining chain efficiently
Chain is made from alternating links – the inner links consist of two plates connecting by two bushings, and the outer links are two plates connected by two pins which go through the bushings of the inner links. The pins are hammered or deformed slightly so they won’t fall out of either side of the bushings. In industrial, high-wear applications, chains also have rollers around the bushings to reduce friction with the sprockets – see Roller Chain:
http://en.wikipedia.org/wiki/Roller_chain
http://en.wikipedia.org/wiki/Roller_chain
Modifying a chain’s length is done with a “chain breaker” tool which holds links in place while a bolt with narrow tip is screwed in from the side to push a pin out of the bushing. The pins are soft enough that the deformations that hold it in place can be bent out of the way by pushing hard enough, and then the chain is broken. (Make sure to oil the bolt to reduce wear on the threads from pressure of pushing pins out.)
To rejoin two lengths of chain, it is necessary to use a master link which takes the place of an outer link. The master link has a plate with two pins, another plate which slides on the pins, and a retaining clip which fits into grooves on the pins to keep the sliding plate on.
To rejoin two lengths of chain, it is necessary to use a master link which takes the place of an outer link. The master link has a plate with two pins, another plate which slides on the pins, and a retaining clip which fits into grooves on the pins to keep the sliding plate on.
The master link can be disassembled with a pair of pliers by pinching on the open end of the clip and one of the pins – that pushes the clip enough to widen its jaws off the pins.
Because chain length is only adjustable by two links at a time, it’s useful to have an adjustable idler sprocket that can take up some slack, or if you’re using a motor with a sprocket, measure the chain length with the motor spindle in a middle position in the motor bracket.
Motor spindle in a middle position of the motor bracket – sprocket removed for clarity. Chain length would be measured with sprocket in place.
Once the chain loop is rejoined, you can adjust the motor and sprocket position for the desired tension by moving the spindle higher or lower.
One last tip – position the retaining clips on the side of the chain where they’ll be easier to find and access in case you need to take them off in the future.
Let us know if you have any further questions or found this helpful by filling out the forum below.
Once the chain loop is rejoined, you can adjust the motor and sprocket position for the desired tension by moving the spindle higher or lower.
One last tip – position the retaining clips on the side of the chain where they’ll be easier to find and access in case you need to take them off in the future.
Let us know if you have any further questions or found this helpful by filling out the forum below.