Not so long ago, Team Unlimited was given an opportunity to meet with some senior members of the FTC leadership. We got to talk with them for a few hours about the program, kits, etc. Below are our notes in Q&A form.
Q: How many controllers can be operated on the new system?
A: Two controllers can be used to operate the NXT for the new FTC challenge. The system is laptop based and transmits controller data to the NXT through a blue tooth dongle. In competition there will be a central computer being operated to control all the rounds. Each NXT has a unique address that allows Bluetooth signals to be sent to it in order to perform functions during operator mode.
Q: What does the controller connect to in order to operate properly in operator mode? Are there any limits on the amount of robots that can be run at any given time?
A: As stated above, a central competition computer will run the rounds. Switching out of autonomous mode will be determined by this computer also. The Bluetooth dongle on this computer will communicate to NXTs on the field. There is no theoretical limit for this system, but a practical limit must be introduced or else a lag occurs in the system with too many signals being received and transmitted.
Q: How are the drive motors controlled? (e.g. H-bridge, speed controller, etc.)
A: There will be multiple “black boxes” mounted on the robot to control the motors, daisy chained to a single NXT sensor port. There are 2 of the DC controllers units (each DC controls two motors) and 1 of the servo control units (driving up to 6 servo motors). LEGO NXT motors are controlled directly though the NXT controller.
Q: Who are the new sponsors for next years providing the metal, sensors, programming, etc.?
A: HiTechnic, National Instruments, and Pitsco (LEGO Education). Pitsco is proving a large portion of the metals for the new kit, custom made.
Q: Are the parts in this kit commercially available?
A: Yes, the providers of the parts realize that the parts will be under stresses from usual competition strains. Seeing this, new parts will be available in the form of kits, such as a metals kit that includes a selection of metals in one kit. (NOTE: This is similar to the Aluminum kit that Vex provides that has many metals in one kit, no idea on prices yet)
Q: For next season, will teams be able to buy more of these metals, sensors, etc.? Will there be kit restrictions?
A: Teams will be able to purchase new parts for the kits, for spares, additions, etc. Dealing with kit restrictions, the teams will have their electronics limited, including motors and sensors.
Q: What is the average range for the controller in operator mode?
A: The range for this system is about 30-50 ft, more than needed to run on the competition field. One can see a substantially larger distance depending on the particular dongle and area where the robot is being driven. (e.g. a large open room without obstructions will get a much larger range than a cluttered room full of boxes).
Q: How many types of wheels will be available in the kit?
A: There are two sizes available in the kit as of right now. In the demo, most of the teams used the larger wheel to get more speed from their robot, but there were two wheel sizes included in the kit.
Q: How many control channels are available?
A: There are two joysticks, an eight way d-pad, and eight buttons. (NOTE: The controller we used was similar to the Logitech PS2)
Q: What vex components in addition to the metal can be used next season? (e.g. wheels, gears, chain, etc.)
A: For the time being only the Vex metal will be allowed to be used in the competition for next year.
Q: Will we able to modify the Lego and metal components?
A: You will be able to modify the metal components as you have been allowed to for FTC competition for the 2007-2008 season. The Lego components will not be allowed to be modified at the current time for competition.
Q: Will there be a rotation sensor provided in the kit?
A: Yes, there will be a rotation sensor in the new kit. The one that was installed on the demo robot (they were US Digital rotation sensors) may not be the final sensor included in the when it is released.
Q: How open is the kit? Can we use components not provided in this kit? (e.g. other metals, other sensors, etc.)
A: The kit will be relatively closed, there will be the ability to buy new metal for the kit. There is the possibility of other materials being added to the kit to allow teams to fabricate parts for their own use.
Q: Will there be continuous rotation servos that can be purchased for the kit?
A: There will be 170º / 180º servos. No regular servos can be used besides the NXT Lego motors provided with the kit. The 170º / 180º servos will not be allowed to be modified to become continuous rotation servos. The servos in the kit were HiTec 475 servos.
Q: Will there be more sensor connections available? (e.g. connection extenders)
A: There will be one daisy chained box for four touch sensors. There is the possibility for other connection extenders being provided at a later date for other sensors besides the touch sensors.
Q: Has the strength of the connection between the metal and Lego components been improved? Several teams expressed concern about this after collisions that caused the Lego components to fall off.
A: These connection points have not been altered since the demo exhibition. (NOTE: On the robot we were shown, the connections did not seem to been weak at all).
Q: For the Bluetooth dongle, are there any recommendations? Are there any dongles that are best?
A: The DLink DBT120 is recommended. In the kit there is a dongle provided. Bluetooth dongles that don’t require the installation of additional drivers over the Microsoft drivers are best as they cause fewer problems for the users. Loading a driver might add complications cause problems for the robot. (NOTE: They said Toshiba chipset dongles seemed to cause problems in testing, might want to avoid these).
Q: Are there any problems with the Bluetooth system currently?
A: There seems to not be any problems once the link is established. The only major problem occurs if the user unplugs the dongle during an active connection to the NXT. To fix this remove the batteries from the NXT, reset, and reconnect the controller.
Q: Are there any there any changes to the competition format for next year?
A: Nothing too major will change; they would like to see the use of more sensors by teams in the competition.
Q: Are there any major kit changes that will occur from between now and when the kit is released?
A: The optical shaft encoders that are on this robot might not be the final encoders at the time of the kits release. Also the DC & Servo motor control units will have a redesign for esthetics, not for function.
Q: Is there a limitation for the number of “channels” for the new Bluetooth communication system?
A: No, but there is a problem when too many signals are in the same area. There might be a tether, like for Vex, in the pits to cut down the chatter in the network.
Q: How much of a kit was used to make the demo robot here?
A: The robot shown here is about 2/3 of the kit planned to be provided.
Q: What is the material on the bottom of this robot, and will we able to use this in competition?
A: This is a sheet of polycarbonate. We are hoping to provide some material like this to the teams so that they can use it for shielding, decoration, etc. in the competition.
I hope you all like this!
~Patrick Pilvines, Head Engineer Team Unlimited, FTC #1
I will provide a link to our site ((http://eaglevex.syraweb.org)) to the offical page, when we get all the photos processed.