You can create a Value Type and then specify the Quantity Kind and Unit it uses.
Note that the SysML profile includes standard SI Definition Value Types that you can use, such as kg, m and N - the SI Definition Units are provided in sub-Packages of the SI Definitions package.
To create a value type:
1. Right-click the Model or Package in which you want to create the Value Type, point to New, point to SysML, point to Structure, point to Value Type, and then click the required Value Type command. The following commands are available:
◦ Alias
◦ Array
◦ Basic Type
◦ Data Type
◦ Enumeration
◦ Sequence
2. Type the required name of the Value Type, and then press the Enter key.
3. For Value Type (Enumeration) items only, create its enumeration literals. To create an Enumeration Literal:
a. Right-click the Value Type, point to New, point to SysML, and then click Enumeration Literal.
b. Type the name of the Enumeration Literal, and then press the Enter key.
Alternatively, you can create a Value Type on a Block Definition Diagram.
How?
To specify a value type's quantity kind:
1. Right-click the Value Type, point to Links, and then click Quantity Kind.
2. To use an existing Quantity Kind:
a. Select the Existing Item option.
b. Select the Quantity Kind that you want to use, and then click OK.
To create a new Quantity Kind to use:
a. Select the New Item option.
b. In the Name box type the name of the Quantity Kind that will be created, and then click OK.
To specify a value type's unit:
1. Right-click the Value Type, point to Links, and then click Unit.
2. To use an existing Unit:
a. Select the Existing Item option.
b. Select the Unit that you want to use, and then click OK.
To create a new Unit to use:
a. Select the New Item option.
b. In the Name box type the name of the Unit that will be created, and then click OK.
To unset a value type's quantity kind or unit:
1. Right-click the Value Type, point to Links, and then click Quantity Kind or Unit.