If you wish to transmit a measured parameter under US FCC Part 97 regulations, you would be operating under the telemetry rules. This is defined as "A one-way transmission of measurements at a distance from the measuring instrument."
Telemetry transmissions are generally permitted under the same conditions that "Data" transmissions are permitted.
The issue of automatic control is a distinct topic. Automatic control means there is no control operator at a local or remote control point. For 6 meters and shorter wavelengths (e.g.VHF and UHF transmitters) automatic control of data (and thus telemetry) transmitters is permitted:
97.221 Automatically controlled digital station.
(a) This rule section does not apply to an auxiliary station, a beacon station, a repeater station, an earth station, a space station, or a space telecommand station.
(b) A station may be automatically controlled while transmitting a RTTY or data emission on the 6 m or shorter wavelength bands, and on the 28.120-28.189 MHz, 24.925-24.930 MHz, 21.090-21.100 MHz, 18.105-18.110 MHz, 14.0950-14.0995 MHz, 14.1005-14.112 MHz, 10.140-10.150 MHz, 7.100-7.105 MHz, or 3.585-3.600 MHz segments.
Depending upon your specific implementation choices, other rules and limitations may apply.