The SSC-32 is supposed to have 4 inputs either analog or digital. The question is, how would I connect a Sharp GP2D12 IR Sensor to the SSC-32 so that it could be read. I am currently sending commands to the servos from a VB program and this works great. I would like to be able to detect something from a sensor. I have the GP2D12 and thought that would be a good start.
I have a Lynx 6 arm and would like to find a sensor that can detect the weight of a coin (different sensor) . I want to program the arm to take several coins, sort them then give me the total. My VB program can handle the logic and moving the arm is not a problem. I just need to be able to read a sensor (yet to be found) that can return a weight of some type. It doesn’t need to be the actual weight but it needs to be able to tell the difference between a penny and a dime. If anyone has any suggestions I would be glad to hear them.
I know there are pressure sensors but I have never used them and I have no idea as to how sensitive they are. Basically they send a varying voltage signal as the contacts are smashed.
I don’t know anything about rangefinders, so I can’t help you there.
But, I’m sure that someone else definitely can.
You can find a nice range of sizes in pressure sensors at http:/www./phidgestusa.com/
I’ll be using eight of the .2" FSR’s (Force Sensing Resistors) on my biped’s feet.
I’m not sure as to the accuracy of the sensors themselves.
I read a document that indicates that companies use varying conditions and stipulations when talking about the accuracy of their pressure sensors.
So, comparing the accuracy of one sensor that’s only tested in room temperatures to another that’s only tested with 4.99V - 5.01V is like comparing apples and oranges.
The only real way to tell how well these types of sensors work is to ask someone who already has used them.
NickA (a biped builder on these forums) says that they work rather well, so I’m content to believe him.
All those sharp sensors output a single analog value to indicated the distance. It’s as simple as connecting the output pin to your analog pin on the micro.
As for the weight issue, there are lot of USB and serial scales for weighing mail. Perhaps you could hack one of these up? If it’s not too uncool, might you leave it untouched and pick and place things onto it for a reading?
Mike, thanks for the link to flexiforce sensor. I had not found that one.
Nick, when I last looked at Phidgets, I didn’t look thoroughly enough. I had only registered that their components only worked with their Interface kit and their COM component. My thoughts are to design and test the system using VB but have the ability to eventually program a microprocessor (such as a PIC, Basic Atom, OOPic, etc) to do the work in the future. I wanted to stay away from the proprietary COM component.
After your suggestion I went back a looked again. They do sell a 1.5 Inch FSR Sensor Kit with (2) 1.5 inch force sensors that may do the trick. At $17.95 for 2 sensors plus cables and resistors this looks like the best deal. Now I will just need to figure out how to connect them to the SSC-32 so that they can be read.
Andylippitt, the mail scales were my first thought as well. I actually have a couple of serial postal scales and tried to play around with them but would prefer something that can interface directly with the SSC-32.
Your statement “It’s as simple as connecting the output pin to your analog pin on the micro.”
The Sharp GP2D12 IR Sensor I got from Lynxmotion has a servo type female connector that has 3 lines. The SSC-32 inputs (A,B,C,D) have only 2 pins.
The question I had was can I just plug the + and output lines onto those 2 pins? Does the ground need to be connected to something as well? Are resistors or some other component required to protect the SSC-32 electronics?
The three pins are 5V, gnd, and an analog output. Hopefully someone who knows the ins and outs of the SSC32 can chime in here with the specifics of getting it running with that board.
The three connections on the GP2D12 are for ground, power and analog. The analog signal is used to determine the distance based on voltage. You can connect the analog line to one of the 4 A2D inputs on the SSC-32. The power needs attached to the regulated 5v output and the ground can tie in anywhere. You can tie these wires directly to the board without resitstors or anything. However you may want to add a small 4.7uf capacitor between the ground and analog signal.
The next challange will be calculating distance from the digital value returned from the SSC. If you do some googling I think you could find a lookup table to calculate the distance.
Sincerely,
David Garske
Wibotics, Inc. wibotics.com
The easiest way to connect the GP2D12 using our cable, would be to pull the connectors out of the black plastic housings, and install some heat shrink on the individual connectors to prevent them from shorting out against something. Then you can plug the black wire onto the (-)pin and the red wire onto the (+)pin where the ABCD inputs are located. Then of course plug the yellow wire onto the ABC or D pin. Hope this helps…
