Re: New Sensors?
 

That lightWare Lidar is Class 1M ... The rules (So far) state it has to be class 1. Lidar-lite just got approved as a class 1 for its laser version and they do have an LED version that does not require any Classification.

http://pulsedlight3d.com/pl3d/wp-con...Data-Sheet.pdf

Re: New Sensors?
 

New sensors for new sensors' sake will just be a gimmick that very few teams end up using successfully (like the camera has been in many years). There would need to also be a game mechanic that requires the new sensor.

I would personally love to see an end-of-match autonomous mode, which necessitates very good localization. Up until now, teams could get by on using odometry from a known starting position and be (reasonably) repeatable over 10-15 seconds. Remove the ability to precisely control the initial conditions of the robot and it is a whole different animal.

Robocup uses a top-down, whole field camera as previously mentioned. This might be infeasible, but attaching a high resolution camera (with high intensity LED rings) rigidly to a goal or field element would be really, really cool. The field would then send the images over wired Ethernet to the player station and would let teams detect their own robot in the video stream on the driver's station. You could then do localization (or even visual servoing) based on the feed and send commands to the robot.

Advantages of this proposal:
0) Robots that can work from semi-arbitrary starting conditions would be HELLA COOL.

1) Since 2005, the vision challenge has always been to detect a given feature of the field or game element. Instead, turn the challenge on its head and let teams have to devise their own fiducials (using retroreflective tape or otherwise). Designing good features to detect, localize, and track is a tough engineering challenge!

2) Field WiFi network doesn't need to carry image data, so no bandwidth hiccups and latency problems like we've seen for the past few seasons.

3) Teams don't need to worry about mounting a camera to their robot (expensive, complex, occasionally flaky, fragile, etc.).

4) Teams only need a sensor and a laptop to do the programming. Gives the programmers a meaningful task on day 1!

A variation on this proposal would be to have a protected area of the field/beside the field (with ethernet cables and power supplied) where teams can position their own custom camera (or other) sensor prior to the match. This eliminates the need for every team to acquire one of the official field sensors and could allow for even more creativity.

Re: New Sensors?
 

It's clear the Google car and its brethren will be real very soon, and in fact its the social, not the technical, challenges which will dominate. I for one don't want to wait for FIRST to design games that will require this technology - I believe we need to develop it now, and I believe once developed it will be both very usable in current games, and future-ready when drivers have to focus on problems of a higher order than vehicular navigation.

Two lynchpin sensors:

A) A $79 LED-based optical ranging system (Lidar-Lite) is being released this month. We're planning on building a 2-D 360 scanning lidar, the goal is to range the entire field (at robot height) at 1-2 degree resolution within about 3 seconds.

Lidar Lite (http://www.dragoninnovation.com/proj...-pulsedlight):

- Uses LEDs, not Lasers, w/an optic. Repeat: NO LASERS REQUIRED.
- Measures distance to 20 meters with a 10ms integration period using time-of-flight calculations
- Notably, provides SNR measurements for each calculation. Key point: We should get much higher SNR for ranging retroreflective tape than other surfaces.

B) An auto-calibrating Attitude Heading Reference System (AHRS). The nav6 IMU we developed for FIRST (https://code.google.com/p/nav6) provides this solution; this was used by several teams at nationals last year and includes C++, Java and LabView Libraries for easy integration onto the robot.

Given knowledge of the field metrics, these two intelligent sensors together provide:

- Robot Current Position relative to Field (derived from field metrics and 360 degree lidar scan) throughout the match.
- Robot Starting Orientation (measured w/magnetometers before game (and motors) start).
- Instantaneous Orientation (100Hz Motion Fusion of Gyro/Accelerometer).
- Gravity-corrected Linear Acceleration measurements
- Angle to Retro-reflective Tape (based on SNR thresholds of LIDAR data).

And unlike camera-based approaches, we believe this approach should be insensitive to variable lighting conditions.

The nav6 sells for $70. And I'm estimating we can build the Lidar Lite for about $150 in parts, not sure what we the sale price to the FIRST community might be yet.

Now of course on top of that we need collision avoidance and waypoint navigation algorithms. But the amount of published research done in this area recently (not to mention some cool Cheesy Poofs navigation code :P) is rapidly making this an engineering, not a research, task.

It's a good time to be a robotics engineer!

Re: New Sensors?
 

The Lidar-Lite looks to be an inexpensive and capable sensor. But it is new and untested by the masses in the wild. I've seen other efforts like this fall far short of claims when the real product was shipped. For that price it's worth giving it a shot. An inferred Led may just be good enough.

As to the nav6 - Invensens is now releasing their code for 9 axis sensor fusion. Up to now they only released this to their high volume partners. Fusing in the mag with these libraries may make the nav 6 way better with just a code update.

PNI corp released a new 9 sensor fusion asic this spring that has shown superior magnetic corrections with cheap mags.

Astrial navigation is do able at most venues. It does need cpu horse power.

Re: New Sensors?
 

Yes. The new Invensense Motion Driver 6.0 beta release occurred yesterday. We are now developing the nav6's bigger brother, the nav9, by using the MPU-9250, and featuring an STM32 ARM MCU to host the Invensense MPL library, which only ships in binary form (forcing the move to a new processor).

This gives full 9-axis motion fusion, including:

- magnetic disturbance detection
- improved Magnetometer calibration, incl temperature shift correction
- better support for pre-match and factory calibration
- faster dynamic calibration

Also adding USB, I2C, SPI interface options.

Thinking of adding a CAN interface too, but not sure the extra circuitry keeps it within the budget of most FIRST teams.

Re: New Sensors?
 

They would have to introduce this concept slowly. It might be interesting to have a game that utilizes RFID or a similar technology for the identification of game pieces. Perhaps a basic matching type game (put correct game piece in correct zone) as either the endgame or autonomous mode.

Re: New Sensors?
 

I really want to see an autonomous mode where FRC robots have to sort out different game elements to gain points. That would be awesome.

Re: New Sensors?
 

In auton mode if your robot can switch off the any opponent robot, 25 bonus points. If the opponent's partner can turn it on again, 50 bonus points.

Re: New Sensors?
 

For those interested in following Lidar-Lite developments, PulsedLight3d has published detailed technical information, including a preliminary user manual just released a few days ago:

http://pulsedlight3d.com/technical-stuff-2/

I'm happy to see the level and quality of detail they're providing, and am really looking forward to getting some real-world metrics; I'll plan to post these soon after we get our hands on the first units.

Re: New Sensors?
 

One of my mentors waaaaaaaay back on 294 (and still a mentor) was on the very successful Cornell team, and told us about this method.

Ever since then I thought it'd be awesome for FIRST to implement. It's very achievable and a completely new twist on everything.

Re: New Sensors?
 

Teams could still control the initial position of robots -- though not as precisely -- by driving into position before the auto/endgame.

For example, take the 2013 endgame. 10 point teams could have driven into the pyramid, and then once the auto commences, just throw their solenoids/engage their hanger. The same goes for 2011 or 2010.

Now 2012 -- that would be a hard endgame for the majority of FRC teams to pull off autonomously.

Re: New Sensors?
 

Looks like the Lidar-lite just went up for sale. http://pulsedlight3d.com/products/lidar-lite

Re: New Sensors?
 

$89, 40 meter range, and 0.02 second aquisition. That sounds incredible! I can't wait for a SLAM demonstration

Re: New Sensors?
 

2014 rules would mean this whole thing(as one individual item) would have to cost less than 400$. 2 new talons, or old jaguars (CAN) already puts you at 160$. Add a 2 motor gearbox, 2 CIMs, and an encoder, you're really pushing it. If its mostly assembled, as I assume you'd want, you have to pay people to assemble the thing. Not saying its impossible, but it sounds like a hard thing to make under 400$. Also, rules can change.

Also, a one CIM gearbox is seems very feasible, and a team could buy 4, I suppose.

Edit: alternately, the gearbox could include talon mounts, and a team could buy them separately, this would be technically legal due to the assemble being functional another way but this is a slippery slope.