I would like to build a pendulum from scratch and model/control via Matlab. I don't know what DC motor should I use that has low friction (low static friction), so the pendulum can rotate by its self. Moreover, I would like to have an encode with "good" precision, less then 1^o. I want to control the position of the pendulum by using the motor to put energy in the system. It will be a closed loop control and the controlled variable is the voltage drop on the motor. How to check in a technical specification if the motor has low static friction?
Eg. the technical specification for a motor include:
Values at nominal voltage: Nominal voltage; No load speed; No load current; Nominal speed; Nominal torque (max. continuous torque); Nominal current (max. continuous current); Stall torque; Starting current; Max. efficiency; Terminal resistance; Terminal inductance; Torque constant; Speed constant; Speed / torque gradient; Mechanical time constant; Rotor inertia.