Rotary Sensor Help

I am currently in a low level engineering course and have to build a device that measures angle and outputs it on a screen. I was looking a the grove rotary sensor and after some research I kind of get the idea behind doing it but i still really don't know what I am doing. So far I understand I need the following:

Base shield
rotary sensor
led screen
power supply

Not sure if thats everything that I need, and I am not really sure how to build it.

Another thing is when reading the introduction to the base shield it said when connecting it to the computer to add code that u should connect a temperature sensor. Why is this necessary?

Anyone care to help a newbie? :stuck_out_tongue:

Not sure if thats everything that I need

I'm sure that someone, sooner or later, will recommend that you get an Arduino, too.

Another thing is when reading the introduction to the base shield it said when connecting it to the computer to add code that u should connect a temperature sensor. Why is this necessary?

No idea what you are talking about. Post a link to the "base shield" you are talking about.

Ya I just did some more research and saw the Arduino Uno that the Grove Base Shield is compatible with. Is the power source incorporated into that?

and here is the link. Its step 1

The photo and code in section one is just to illustrate one device, and the code to interact with it. You don't need a temperature sensor unless you want one.

I don't think that shield will even be all that useful to you. It would not be one of my first purchases.

What are you trying to measure the angle of? Something that you can attach a sensor to, like a rotary encoder, or something that moves, like a game controller? That would determine the type of sensor that you need.

So essentially I have to make an electric goniometer which is used in physical therapy to measure the range of motion of a joint by aligning it with an arm or another body part

mrw0816:
So essentially I have to make an electric goniometer which is used in physical therapy to measure the range of motion of a joint by aligning it with an arm or another body part

Is there some reason not to use a rotary potentiometer as the angular sensor? If that's an option it would be the most obvious approach.

PeterH:
Is there some reason not to use a rotary potentiometer as the angular sensor? If that's an option it would be the most obvious approach.

Please elaborate lol, because i really dont know to much of what I am doing but i believe the grove rotary sensor that i was looking at was a potentiometer

mrw0816:
Please elaborate lol

A conventional rotary pot has a housing with a spindle sticking out. The spindle turns relative to the house. Attach the housing to one side of the joint and attach the spindle to the other, so that they move relative to each other as the joint flexes.

Imagine something like two 12" rulers connected by a pivot at one end. Arrange to mount that on the joint so that the pivot lines up with the center of movement of the joint. Then attach the pot housing and shaft to the two rulers so that as the two rulers move relative to each other they rotate the pot.

That is essentially what I am trying to go for, I am just not sure of all the parts required to build it.

You'll need the following:
-Arduino Uno
-LCD Shield
-Potentiometer/Rotary Encoder
-Power Supply
Look here for how to use a potentiometer

Look here for how to use a rotary encoder
http://playground.arduino.cc/Main/RotaryEncoders

Look here to use one kind of LCD screen (there are many)

Look here for options for a power supply. It is common to use a 12V wall wart.

Also note that potentiometers have a limited range of motion where a rotary encoder does not.