# Belt drive¶

Belt drive link properties implement a toothed belt drive. Only the linear elastic behaviour is modelled, non-linearities are neglected. The simplifications are:

• the belt is always considered prestressed (both strands are contributing to the stiffness)

• the prestress force is not modelled and has to be added as load in an analysis if desired

• irregular transmission due to the teeth is not modelled

• local deformation of the pulleys is not modelled

## Definition¶

Source and target interfaces should be chosen as shown in following figure:

### Source interface¶

 Type Stationary interface (6dof) Topologies Peripheral face of the source pulley Location Center of the source pulley u direction Axial, along the axis of rotation of the source pulley v direction Arbitrary w direction Arbitrary

### Target interface¶

 Type Stationary interface (6dof) Topologies Peripheral face of the target pulley Location Center of the target pulley u direction Axial, along the axis of rotation of the target pulley v direction Arbitrary w direction Arbitrary

## Parameters¶

Parameter

Unit

Symbol

Description

m

$$r_S$$

Radius of the pitch line of the source pulley

m

$$r_T$$

Radius of the pitch line of the target pulley

Belt stiffness

N/m

$$k$$

Stiffness of one strand of the belt including tooth compliance

Belt viscous damping

Ns/m

$$d_v$$

Viscous damping coefficient of one strand of the belt

Belt hysteretic damping

None

$$d_h$$

Hysteretic damping coefficient of one strand of the belt

The stiffness of the belt can be calculated using the specific stiffness $$c_{st}$$, the width of the belt $$b$$, and the free lenght of a strand $$l_{1}$$ according to $$k = c_{st} \, b / l_1$$.