Tested functionality with hand hardware.

Arduino/simple_hand_driver/simple_hand_driver.ino

@@ -5,6 +5,7 @@ int pinArray[2][9] =
   {12, 10, 8, 6, 4, 13, 15, 17, 19},  
   {11, 9,  7, 5, 3, 14, 16, 18, 20}
 };
+int prevDir[9] = {0, 0, 0, 0, 0, 0, 0, 0, 0};
 
 void setup() {
   // put your setup code here, to run once:
@@ -39,12 +40,24 @@ void move_motor(int id, int dir){
   if(dir == 1){
     digitalWrite(pinA, LOW);
     digitalWrite(pinB, HIGH);
+    prevDir[id] = 1;
   }
   else if(dir == -1){
     digitalWrite(pinA, HIGH);
     digitalWrite(pinB, LOW);
+    prevDir[id] = -1;
   }
   else{
+    if(prevDir[id] == 1) {
+      digitalWrite(pinA, HIGH);
+      digitalWrite(pinB, LOW);
+    }
+    else if(prevDir[id] == -1) {
+      digitalWrite(pinA, LOW);
+      digitalWrite(pinB, HIGH);
+    }
+    delay(8);
+    prevDir[id] = 0;
     digitalWrite(pinA, LOW);
     digitalWrite(pinB, LOW);
   }

Python/.gitignore

+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[cod]
+*$py.class
+
+# C extensions
+*.so
+
+# Distribution / packaging
+.Python
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
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+lib/
+lib64/
+parts/
+sdist/
+var/
+wheels/
+share/python-wheels/
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+.installed.cfg
+*.egg
+MANIFEST
+
+# PyInstaller
+#  Usually these files are written by a python script from a template
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+docs/_build/
+
+# PyBuilder
+.pybuilder/
+target/
+
+# Jupyter Notebook
+.ipynb_checkpoints
+
+# IPython
+profile_default/
+ipython_config.py
+
+# pyenv
+#   For a library or package, you might want to ignore these files since the code is
+#   intended to run in multiple environments; otherwise, check them in:
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+
+# pipenv
+#   According to pypa/pipenv#598, it is recommended to include Pipfile.lock in version control.
+#   However, in case of collaboration, if having platform-specific dependencies or dependencies
+#   having no cross-platform support, pipenv may install dependencies that don't work, or not
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+#Pipfile.lock
+
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+#   commonly ignored for libraries.
+#   https://python-poetry.org/docs/basic-usage/#commit-your-poetrylock-file-to-version-control
+#poetry.lock
+
+# pdm
+#   Similar to Pipfile.lock, it is generally recommended to include pdm.lock in version control.
+#pdm.lock
+#   pdm stores project-wide configurations in .pdm.toml, but it is recommended to not include it
+#   in version control.
+#   https://pdm.fming.dev/#use-with-ide
+.pdm.toml
+
+# PEP 582; used by e.g. github.com/David-OConnor/pyflow and github.com/pdm-project/pdm
+__pypackages__/
+
+# Celery stuff
+celerybeat-schedule
+celerybeat.pid
+
+# SageMath parsed files
+*.sage.py
+
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+.env
+.venv
+env/
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+ENV/
+env.bak/
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+
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+.spyderproject
+.spyproject
+
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+.ropeproject
+
+# mkdocs documentation
+/site
+
+# mypy
+.mypy_cache/
+.dmypy.json
+dmypy.json
+
+# Pyre type checker
+.pyre/
+
+# pytype static type analyzer
+.pytype/
+
+# Cython debug symbols
+cython_debug/
+
+# PyCharm
+#  JetBrains specific template is maintained in a separate JetBrains.gitignore that can
+#  be found at https://github.com/github/gitignore/blob/main/Global/JetBrains.gitignore
+#  and can be added to the global gitignore or merged into this file.  For a more nuclear
+#  option (not recommended) you can uncomment the following to ignore the entire idea folder.
+#.idea/
\ No newline at end of file

Python/hand_controller.py

@@ -4,6 +4,8 @@ def main():
     arduino = Arduino("Hand motor controller Arduino", "/dev/ttyACM0", 115200)
     key = Key()
 
+    arduino.connect_and_handshake()
+
     fwd_keys = ["1", "2", "3", "4", "5", "6", "7", "8", "9"]
     rev_keys = ["q", "w", "e", "r", "t", "y", "u", "i", "o"]
     while 1: