An apparatus, comprising: a wheel engagement unit configured to suspend a tire-wheel assembly; at least one inflation unit configured to inflate the tire-wheel assembly; wherein each inflation unit includes probe stirrup (20, 20') and an air inflation probe (18, 18'), the air inflation probe (18, 18') being configured for insertion into a cavity formed by the probe stirrup (20, 20'); the apparatus being characterised in that it further comprises: a load cell configured to sense an amount of strain being applied to the tire-wheel assembly; wherein said load cell monitors a first force applied to the load cell via the tire-wheel assembly and a second force applied to the load cell via a robotic arm that is coupled to the at least one inflation unit; wherein the first force and the second force are directed in substantially opposite directions; a controller configured to: monitor the load cell by receiving a load signal from the load cell during inflation of the tire-wheel assembly, determine an internal air pressure of the tire-wheel assembly based on the load signal, and control the at least one inflation unit based on the determined internal air pressure of the tire-wheel assembly; wherein controlling the at least one inflation unit comprises determining whether to continue inflating based on the internal air pressure. a wheel engagement unit configured to suspend a tire-wheel assembly; at least one inflation unit configured to inflate the tire-wheel assembly; wherein each inflation unit includes probe stirrup (20, 20') and an air inflation probe (18, 18'), the air inflation probe (18, 18') being configured for insertion into a cavity formed by the probe stirrup (20, 20'); the apparatus being characterised in that it further comprises: a load cell configured to sense an amount of strain being applied to the tire-wheel assembly; wherein said load cell monitors a first force applied to the load cell via the tire-wheel assembly and a second force applied to the load cell via a robotic arm that is coupled to the at least one inflation unit; wherein the first force and the second force are directed in substantially opposite directions; a controller configured to: monitor the load cell by receiving a load signal from the load cell during inflation of the tire-wheel assembly, determine an internal air pressure of the tire-wheel assembly based on the load signal, and control the at least one inflation unit based on the determined internal air pressure of the tire-wheel assembly; wherein controlling the at least one inflation unit comprises determining whether to continue inflating based on the internal air pressure. a load cell configured to sense an amount of strain being applied to the tire-wheel assembly; wherein said load cell monitors a first force applied to the load cell via the tire-wheel assembly and a second force applied to the load cell via a robotic arm that is coupled to the at least one inflation unit; wherein the first force and the second force are directed in substantially opposite directions; a controller configured to: monitor the load cell by receiving a load signal from the load cell during inflation of the tire-wheel assembly, determine an internal air pressure of the tire-wheel assembly based on the load signal, and control the at least one inflation unit based on the determined internal air pressure of the tire-wheel assembly; wherein controlling the at least one inflation unit comprises determining whether to continue inflating based on the internal air pressure.