diff --git a/src/lib/mixer/mixer.h b/src/lib/mixer/mixer.h
index 5bf02129cb..b6572f5396 100644
--- a/src/lib/mixer/mixer.h
+++ b/src/lib/mixer/mixer.h
@@ -241,7 +241,7 @@ public:
 	virtual unsigned get_trim(float *trim) = 0;
 
 	/*
-	 * @brief      Sets the thrust factor used to calculate mapping from desired thrust to pwm.
+	 * @brief      Sets the thrust factor used to calculate mapping from desired thrust to motor control signal output.
 	 *
 	 * @param[in]  val   The value
 	 */
@@ -444,7 +444,7 @@ public:
 	}
 
 	/**
-	 * @brief      Sets the thrust factor used to calculate mapping from desired thrust to pwm.
+	 * @brief      Sets the thrust factor used to calculate mapping from desired thrust to motor control signal output.
 	 *
 	 * @param[in]  val   The value
 	 */
@@ -708,7 +708,7 @@ public:
 	}
 
 	/**
-	 * @brief      Sets the thrust factor used to calculate mapping from desired thrust to pwm.
+	 * @brief      Sets the thrust factor used to calculate mapping from desired thrust to motor control signal output.
 	 *
 	 * @param[in]  val   The value
 	 */
diff --git a/src/lib/mixer_module/mixer_module.hpp b/src/lib/mixer_module/mixer_module.hpp
index e60a2847ad..3b0721a78f 100644
--- a/src/lib/mixer_module/mixer_module.hpp
+++ b/src/lib/mixer_module/mixer_module.hpp
@@ -233,7 +233,7 @@ private:
 	DEFINE_PARAMETERS(
 		(ParamInt<px4::params::MC_AIRMODE>) _param_mc_airmode,   ///< multicopter air-mode
 		(ParamFloat<px4::params::MOT_SLEW_MAX>) _param_mot_slew_max,
-		(ParamFloat<px4::params::THR_MDL_FAC>) _param_thr_mdl_fac, ///< thrust to pwm modelling factor
+		(ParamFloat<px4::params::THR_MDL_FAC>) _param_thr_mdl_fac, ///< thrust to motor control signal modelling factor
 		(ParamInt<px4::params::MOT_ORDERING>) _param_mot_ordering,
 		(ParamInt<px4::params::CBRK_IO_SAFETY>) _param_cbrk_io_safety
 
diff --git a/src/modules/px4iofirmware/protocol.h b/src/modules/px4iofirmware/protocol.h
index 3dde775ef6..3cfcee2d12 100644
--- a/src/modules/px4iofirmware/protocol.h
+++ b/src/modules/px4iofirmware/protocol.h
@@ -235,7 +235,7 @@ enum {							/* DSM bind states */
 
 #define PX4IO_P_SETUP_MOTOR_SLEW_MAX		24 	/**< max motor slew rate */
 
-#define PX4IO_P_SETUP_THR_MDL_FAC 		25	/**< factor for modelling static pwm output to thrust relationship */
+#define PX4IO_P_SETUP_THR_MDL_FAC 		25	/**< factor for modelling motor control signal output to static thrust relationship */
 
 #define PX4IO_P_SETUP_THERMAL			26	/**< thermal management */
 
diff --git a/src/modules/sensors/motor_params.c b/src/modules/sensors/motor_params.c
index fa625230da..94d246f74b 100644
--- a/src/modules/sensors/motor_params.c
+++ b/src/modules/sensors/motor_params.c
@@ -55,10 +55,14 @@
 PARAM_DEFINE_FLOAT(MOT_SLEW_MAX, 0.0f);
 
 /**
- * Thrust to PWM model parameter
+ * Thrust to motor control signal model parameter
  *
- * Parameter used to model the relationship between static thrust and motor
- * input PWM. Model is: thrust = (1-factor)*PWM + factor * PWM^2
+ * Parameter used to model the nonlinear relationship between
+ * motor control signal (e.g. PWM) and static thrust.
+ *
+ * The model is: rel_thrust = factor * rel_signal^2 + (1-factor) * rel_signal,
+ * where rel_thrust is the normalized thrust between 0 and 1, and
+ * rel_signal is the relative motor control signal between 0 and 1.
  *
  * @min 0.0
  * @max 1.0