Society of Robots - Robot Forum

Mechanics and Construction => Mechanics and Construction => Topic started by: Zhour on August 02, 2007, 10:09:39 PM

Title: Pressure sensor on the sole of the robot?
Post by: Zhour on August 02, 2007, 10:09:39 PM
Right now I'm going to make a legged robot.
I'm planning to make it competent to walk on surfaces that is a bit bumpy.

It seems that I need to put a pressure sensor, or at least a pressure switch(with a threshold pressure, I think) on the sole,  so that the controlling program can use the value returned from the sensor to judge whether the servo is going to rotate or stop.
Obviously the reaction time of the sensor must be short enough.

Any advice for what I should use for this purpose?

Thanks a lot.
Title: Re: Pressure sensor on the sole of the robot?
Post by: Robotboy86 on August 03, 2007, 04:15:48 PM
You mean a sensor that will detect above normal resistance on the servo??  So that when your placing the foot downt hat you can detect when it hits the floor?
If so, you got a few different choices, you could That might work somewhat, but would probaly have flaws.

You couldput a bump sensor there and have it hooked to the bottom that when the bottom hits something, bump switch goes off.


THat could work..  it would be a near instant reaction time to the sensor, but your MCU would depend on how effective it is.  Whether or not you hook it into an intterrupt would matter as well.


k

good luck
Title: Re: Pressure sensor on the sole of the robot?
Post by: JonHylands on August 03, 2007, 08:08:44 PM

Something like this:

http://www.bioloid.info/tiki/tiki-index.php?page=Foot+Pressure+Sensors

- Jon
Title: Re: Pressure sensor on the sole of the robot?
Post by: Zhour on August 04, 2007, 09:32:51 PM
Thank you, Robotboy86 and Jon.

Since in the mechanical design the feet of the robot is supposed to be somewhat like a stick,  it seems to me that both the bump sensor and the pressure sensor are demanding a larger area of contact than the bottom of the stick.Therefore they are somewhat unworkable.

One of my friends suggests using buttons which can often be seen on electronic dictionary. By putting the buttons under the feet we can get to know whether a foot has touched the floor.

In my opinion we don't need to measure the pressure exactly. In stead, knowing whether a foot has touched the floor would be enough for motion controlling.
Title: Re: Pressure sensor on the sole of the robot?
Post by: Soeren on August 04, 2007, 10:12:27 PM
Hi,

Since in the mechanical design the feet of the robot is supposed to be somewhat like a stick,  it seems to me that both the bump sensor and the pressure sensor are demanding a larger area of contact than the bottom of the stick.
You could measure the same impact in the other end of those sticks, as long as they're rigid - perhaps that gives you better room for sensors.
Title: Re: Pressure sensor on the sole of the robot?
Post by: Admin on August 05, 2007, 06:42:36 AM
Quote
Since in the mechanical design the feet of the robot is supposed to be somewhat like a stick,  it seems to me that both the bump sensor and the pressure sensor are demanding a larger area of contact than the bottom of the stick.Therefore they are somewhat unworkable.
Perhaps an accelerometer located on the ankle that detects high shocks?