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  1. Programming leg movements - tibia

    Quote Originally Posted by DiverBob View Post
    I was able to use the same routine I developed for the Femur movement on the Tibia movement. The only difference is the Tibia uses it's own set of ADC values to calculate angles. I am able to use the PST to input angle values to both actuators and the leg responds correctly.

    I started working with the Coxa control but ran into some issues where the position encoder doesn't appear to be sending the HB25 any signals. I've successfully used this combination before so I'm not sure what
    Propeller , ‎ Programming , ‎ Robotics
  2. Programming leg movements

    Quote Originally Posted by DiverBob View Post
    My entry from a few days ago disappeared, must not have gone out correctly. Anyway, I'm off of night shift and am getting used to sleeping during the night again.

    I got a new software routine developed where I send the femur (lift) motor the desired angle and the femur moves to that position. I mapped out all the angle ADC values from 35 (minimum angle) to 155 degrees (maximun angle) in 5 degree increments. I plotted the results and they aren't exactly linear. I was unable to develop
    Propeller , ‎ Programming , ‎ Robotics
  3. Is there a recommended external DAC that works well with the prop?

    I may need to understand this later.....

    Quote Originally Posted by jmg View Post
    One detail to watch if looking for precision, is the way the DUTY mode works, is it is really Pulse Density Modulation.

    The gotcha hiding in PDM, is the tplh and tphl times matter, and any skew will give a change in voltage, especially at large changes in pulse density.

    I believe the scope shot in Fig 11 of AN001, is showing such an effect : notice the step at 50%

    This is somewhat aggravated by
  4. New laptop, computing in heaven..............

    by , 04-24-2012 at 11:58 PM (WBA Consulting's Propeller Project Blog)
    So, my tried and true HP 6715b laptop that was 4 years old began giving me hourly reminders of it's favorite color: blue. Sad to see it go, (ok, not really), but it was replaced with an HP Elitebook 8560p running Windows 7 64 Bit Enterprise with 4GB of RAM. I also got an upgraded second display; a 23" matte LCD running at 1920x1080 resolution.
    Click image for larger version

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  5. Solder with Parallax at the USA Science & Engineering Festival

    This weekend at the Walter E. Washington Convention Center in DC, Parallax will be soldering our fun Scribbler 2 LED Badges. If you have never soldered before this is a great way to get started. Badges are free and our instructional video by Jessica Uelmen, Engineering Manager, will take solderers step by step through the process. Besides soldering, our Boe-Bots will be running around, and the new ELEV-8 Quadcopter will be on display.

    If you’re in the DC area, make sure to stop by booth ...

    Updated 04-24-2012 at 09:13 PM by Lauren Davis

    DIY and Hacks , ‎ Art and Display