update sensor bench

src/sensor_bench/force_calibration.py

@@ -0,0 +1,20 @@
+"""Force calibration coefficients and plot defaults from Orisys viewer2d."""
+
+from __future__ import annotations
+
+# Linear FN → Newtons (y = mx + c), from orisys examples/gui/sensors/adapter.py.
+NORMAL_FORCE_CAL_SLOPE = 3.92685554668795e-05
+NORMAL_FORCE_CAL_OFFSET = 0.0217596967278535
+
+# PyQtGraph force-curve tuning from examples/gui/viewer2d/backend.py.
+FORCE_SAMPLE_RATE_HZ = 30.0
+PLOT_BUFFER_POINTS = 120
+PLOT_WINDOW_SEC = PLOT_BUFFER_POINTS / FORCE_SAMPLE_RATE_HZ
+Y_AXIS_MIN_SPAN = 20000.0
+Y_RANGE_ALPHA = 0.5
+LOWPASS_CUTOFF_HZ = 10.0
+
+
+def calibrate_normal_force(raw_value: float) -> float:
+    """Convert raw normal-force reading to Newtons using y = mx + c."""
+    return NORMAL_FORCE_CAL_SLOPE * float(raw_value) + NORMAL_FORCE_CAL_OFFSET