Inertial Navigation System

Hi I was thinking about prototyping an Inertial Navigation System and was wondering what gyros and accelerometers team 190 used last year in there’s and were they obtained them.

we are doing the same thing. According to our programmer, the program is ready, we just need some accelerometers.

I check small parts, and msc, but they are both more mechanically oriented.

I know they use them in cars for measuring G-Force, so they might be with automotive things

Analog Devices makes some pretty cool Accelerometers and Gyroscopes.

Blarg… a flashback from early last season…

I built an inertia navigation system, based around a Basic Stamp 2. I have the schematics and code someplace, AIM me if u want them (ExtrudedAluminiu)

The system I built was based around a three axis accelerometer and three gyros. The acellerometer and gyro outputs were integrated by op-amps (analog circuits!!) and then fed to an ADC. The BS2 would select the data it wanted, and it would read it in. It worked remarkable well on my desk. =)

I also placed a 1-axis accelerometer, and ADC, and a BS2 into a model rocket. The BS2 was supposed to read the ADC and then store the output in its onchip EEPROM. However when i tested it, the BS2 couldn’t keep up with the incoming data, and I missed large enough chunks that the height that i obtained was useless.

Btw, all the accellerometers i used were from Analog Devices. They work great for projects and FIRST things.

:]

I know that 190 was going to write a white paper or rather we thought we should. Tommorow I will ask the lead designer of the INS about it for you. I know however that the we used a prefab mini controller along with some two axis accelerometers that I believe are normally sold in mass quanities. Also I know that it took a team of 4-5 the six week’s to do altogether.

I did something kind of like that last year, except I did this:

I had a gyro chip, and then rotary encoders on the wheels. I was worried about using an accelerometer, because in order to get position, you need to integrate them twice. So, once the velocity gets off by a little bit, your position will start “drifting.” I never actually tried using an accelerometer; maybe this isn’t as big a problem as I thought.

You may want to check with teams 111 and 308 also.

Andy B.

I talked to rick petty the lead designer of the ins and he said soon he will have a full website on the ins we used in 2k3 when he has it finished ill post it here.

You may want to check out the StangPS presentation that they have on their site if you have not checked it out yet. Here is a link to the original thread about StangPS:

http://www.chiefdelphi.com/forums/showthread.php?s=&threadid=20273&highlight=stangps

Eric

Weren’t we only supposed to use additional electronics form digi-key or future FAI?

*Originally posted by CyberWolf_22 *
**Weren’t we only supposed to use additional electronics form digi-key or future FAI? **

Yes. Digikey sells nice microcontrollers and Future sells angular rate sensors and accelerometers by Analog Devices and other manufacturers. Between these two sources, you can get everything you need to make a nice navigation system.

We bought both the accelerometers and microcontrolers form places other than future and digikey. I’m not really sure about the gyro it could be the one from the kit.

Then wouldn’t your robot be considered illegal.

I have some ADXL2002s (i think) lying around somewhere. They are pretty nifty and extremely sensitive.

Hint Hint: engineering samples

do you think FIRST would object to a coumpas sensor?

I believe you would have to find it at either Digikey or Future Active and I don’t believe they sell them at either location.

I believe that this was used by chiefdelphi this past year is their anyone on the team taht could comment on this

I don’t know if this is what you are looking to do, but…
To quote myself from our robot design in 2002…

"The team’s very ambitious electrical team has developed sophisticated controls, wiring, and programming to navigate the machine. The navigational system compliments the robot design very well. Important symbiotic relationships continue to develop between the electrical and mechanical systems as well as between the drivers and driver feedback systems.

The electrical team of students and engineers has created a system that would enable independent control of the machine by a visually impaired driver. Code named I.D.A.N. (Intelligent Detection, Analysis and Navigation), the system allows the robot to provide audio feedback to a laptop computer.

The cornerstone of this system is a tiny magnetic sensor that will read the earth’s magnetic field. The signal it sends out will identify the direction the robot is facing. This information also establishes the robot’s location within the five zones of the playing field. An optical switch receives a signal every time the robot moves over a line of white tape bordering each zone.

The robot has been installed with optical switches on servomotors, which allow it to “scan” for the goals and correct its path automatically. The optical switches respond to the retro-reflective properties of the tape on each goal. A pressure sensor inside the robot arms will determine that the goal is secure. The Sie-H2O-Bot team looks forward to gaining extremely valuable experience with this very sophisticated system as the season progresses.

Our experimental “Blind Drive” system won us the leadership in controls award in NYC as well."

HERE IS THE ORIGINAL POST WITH MORE INFO

If you want any more info, contact me and I will try and get it.

(Oh, and BTW it was all made 100% legal to FIRST rules in 2002)

I believe you will find them in both. I don’t have a Future catalog handy, but pages 1156 and 1157 of the current Kigi-Key are nothing but digital compass stuff. It is unlikely that digital compasses are a viable option on a FIRST bot. Besides the cost of one with adaqyite resolution being prohibitive, you must remember that magnetrometers + motors(big magnets), and other high current electrical stuff = bs readings.