Drivers: Invalid Python Expression

Support Animation and Rigging
1

Blender 3.2.1

  1. added a driver to the z location of a cube.
  2. added a custom property to the cube and named the property “Height”.
  3. added the custom property as an input variable of the z location driver.
  4. Error: Invalid Python Expression is the result

I’m following a driver tutorial by Gustav Nilsson and am trying to set up a custom property that is controlled by a driver.

Driver screencap:
driver

Custom property screencap:
properties

file:

drivers-delete.blend (832.5 KB)

2

Because you added the custom property to the “object data properties” not the object properties. So in the ID type you need to use object data.

In this case your driver should look like this:

Driver
Driver790×671 46.7 KB

3

Hi @Blender_Gorilla,
is this the issue ?

driver
driver2188×998 235 KB

your updated file with this driver:

drivers-delete1.blend (831.0 KB)

Cheers,
Dj.

4

Thanks, DNorman and DamianJ. If I could check the solution for both of your posts I would but I checked the first one.