Design and Protype

We require a design and prototype for a desk top charging station which will be used for the charging of our mobile tracking units.
The design needs to be of a modular design of say 10 to 20 units per module but can be linked together for larger users of our system.
Attached is some dimensions and the components we have that need to be housed.
The unit will need to be robust as it is a production environment and heavy handed people will be charging them and issuing them out to the users.