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FLL EV3 Robot

This blog post is about our current EV3 robot we're planning to use in the 2023/2024 FLL competition. Some features: 2 large motors for steering. 2 medium motors for attachments.  2 colour sensors for picking up the white and black lines, also used for line squaring. 1 gyro sensor. To enable attachments to be changed as quickly as possible we're using gravity to keep the gears connected, i.e. you don't need to fasten anything to the robot. Every attachment has 2x 12 tooth double bevel gear (part 32270) which comes in contact with the 2x 20 tooth double bevel gears (part 32269) on the robot. The medium motors are horizontally aligned on the robots, but we use 12 tooth double bevel gears to convert that to vertical alignments. These in turn are connected to 20 tooth double bevel gears, and the attachments in turn connect to these 20 tooth double bevel gears with their 12 tooth double bevel gears.  The complete robot is modelled in Bricklink Studio 2 . You can download the rob
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Cloning a WinXP system to Virtual PC

Steps to clone a physical WinXP system to run on Virtual PC:

  1. Create image(s) of your hard drive(s) in .vhd format. WinImage is a 30-day shareware program that does a pretty good job.
    Tip: Do not select the fixed-size image. The vhd file will be the same size as the partition, but you can shrink the image later if you've selected the dynamically expanding option.
  2. Set up a virtual machine using the .vhd images you've created in step 1.
  3. The virtual machine will probably hang when you try to start it in Virtual PC. The reason for this is incompatibilities between the physical hardware and the hardware Virtual PC is simulating. We need to overwrite the Hardware Abstraction Layer (HAL) to force a redetection of all hardware:
    - Boot the Virtual PC using a Win XP boot CD and select the Recovery Console
    - Log on to the Windows partition (I'll assume it is C:\Windows)
    - cd c:\Windows\System32
    - expand d:\i386\HALACPI.DL_ (assuming d:\ is the CD-ROM drive)
    - copy HALACPI.DLL HAL.DLL
    - exit
  4. When the Virtual Machine restarts, it should redetect all hardware.
  5. Install the Virtual PC additions (mount c:\Program Files\Microsoft Virtual PC\Virtual Machine Additions\VMAdditions.iso).
  6. Optional: Run the Virtual PC Precompactor (mount c:\Program Files\Microsoft Virtual PC\Virtual Machine Additions\Virtual Disk Precompactor.iso).
  7. Optional: Shut down the Virtual Machine.
  8. Optional: Use the Virtual Disk Wizard to shrink the VHD images.
  9. Have fun!

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