Extra sensors

VEX V5 General Discussion New Product Ideas
1

I am currently learning and experimenting with the Parallax Board of Education and the BS2px module. I have been examining the variety of sensors and acessories, and I think that Vex should make a couple of these sensors.

These include:

Pressure sensor - 0 to 200 lbs
Temperature sensor
Accelerometer (3 or 2 axis) - we really need this one
PIR Sensor - detects motion at a distance

(not to expensive)

I know that Vex is releasing new products in the near future, but I would strongly recommend the sensors above. They would increase project maneuverability and complexity. I know that most of these sensors can be bought individually, but I would prefer them made or sold by Vex.

                  Technic-R-C
2

i like idea though i dont know wat an

is
the motion sensor can b made using a light sensor with some convex or concave lenses(not sure which one promotes further sight) though it would b better vex made as you said

3

check out this link, it’ll tell you what a 3 or 2 axis accelermoter is.

http://www.parallax.com/detail.asp?product_id=28026

4

I currently use Parallax PING Sensors with my Vex applications. I also use the Parallax Serial Servo Controller with Vex motors.

5

Freescale x-y and z accelerometers (+/-1.5g) are an option for Vex users. I have used the SARD and EVB boards, which provide an object’s orientation to within +/- 1 degree using a Zigbee wireless UART at 38400 Baud. The sensors themselves can be connected to Microchip PIC or dsPIC MCU analog inputs using the 10-Bit or 12-Bit ADC, although they require a 3.3-Volt power supply.

http://www.freescale.com/files/rf_if/doc/user_guide/MC13192SARDUG.pdf
http://www.jandspromotions.com/wirelesschallenge/appnotes/MMA1260D.pdf

6

sry but i still dont understand want an accelerometer
all i do know is it has 3 axis
can u just tell me in one sentence want it does or wat and can be used for
ex. Ultrasonic sensor sends a signal bounces off wall and returns to ultrasonic sensor and sensor tells how long it took to come back or how far away the object is

7

For the longer Description, try the Wikipedia article, Accelerometer.

If you are making a Balancing Robot like the Working Vex Pendulum Balance Robot, you want to know which direction the Robot is falling, so you can make corrections, the Accelerometer will tell you that information…

FWIIW, the Three Little Tubes (Vestibular System) in your Inner-Ear do the same thing as the Accelerometer does for the Robot. (Bet you NEVER THOUGHT you would be getting a Biology Lesson on a Robotics Help forum!)

8

An x-y axis accelerometer measures the pitch angle relative to the Earth’s Gravity vector (think of the up down motion of your wrist) and the yaw angle (your wrist moving side to side). A z axis accelerometer measures the roll angle relative to the Earth’s Gravity vector (twist your wrist clockwise or counter clockwise).

Freescale x-y and z accelerometers (1.5g) are option for Vex users. I have used the SARD and EVB boards, which provide an object’s orientation to within +/- 1 degree using a Zigbee wireless UART at 38400 Baud. The sensors themselves can be connected to Microchip PIC or dsPIC MCU analog inputs using the 10-Bit or 12-Bit ADC, although they require a 3.3-Volt power supply.

http://www.freescale.com/files/rf_if/doc/user_guide/MC13192SARDUG.pdf
http://www.jandspromotions.com/wirelesschallenge/appnotes/MMA1260D.pdf

9

An accelerometer can measure force on either 3 axis’s or it can measure angle or tilt on all 3 axis’s.

An example:

If you have an accelerometer attached to a boxing bag, you can measure the force that you hit the bag with.

or

balancing robot

10

haha you’ll hate me for this, but I just remembered something:

The iPhone has an accelerometer. When you’re viewing photos or are on the web, you can just turn it, and the accelerometer inside detects the change in orientation and turns the screen.

11

are there any accelerometers that can be programed to be use with the VEX system?
if so, how would i go about programing this in eacy c? or would i need easy c pro?

12

any analog accelerometers can easily be used with vex, just plug each analog output per axis to a vex i/o port, try robotshop.ca, hvwtech.com, dimension engineering, they all sell and/or make great accelerometers

13

how would i program it then?

14

You would need either MPLAB or I Easy C pro to program an accelerometer.

15

the users guide on the acclerometer will pretty much tell you everything, just use analog input commands

16

you dont need easyC pro if it’s an analog accelerometer

17

so get it…
if it works keep it
if it doesnt work…
return it?
sounds good to me
in easyc…
what is the code that i need to put into the controller?
and how would i read the forces from the chip?
does anyone have a code for the accelerometer?
if so please post it =D
thanks

18

What is the difference between a gyroscope and an accelerometer? When would you want to use an accelerometer and when would you want to use a gyroscope? And if I wanted to try to do this (LEGO NxtShot 2.0 - cannon controlled by Mindsensors remote - YouTube) with VEX, which one would I use?

Thanks

19

An accelerometer measures linear acceleration along certain axises (i.e., x,y & z axes).

A gyroscope is a device that resists angular acceleration, and so would be better suited as a tilt or yaw sensor.

As for building a stationary turret: you don’t seem to need either (Based on what I saw on the video).

20

What I meant was the hand controller. If you watch again he has something in his hand and as he tilts it, the turret tilts. I am more interested in the hand controller and tilting mechanism then the actual turret. Based on what you said it seems that it would be better to use a gyroscope in this situation…