A remote control apparatus includes: a main controller, a wireless transmission chip, a gyroscope chip and an operating device; wherein the wireless transmission chip is electrically connected with the main controller; the gyroscope chip is electrically connected with the main controller; the operating device is electrically connected with the main controller. The gyroscope chip is used for detecting an inclination angle of the remote control apparatus relative to a horizontal plane, and sending a first electric signal representing a positioning status of the remote control apparatus to the main controller. The main controller is used for detecting an input level when the operating device is operated by an operator, and sending a second electric signal representing a movement direction instructed by the operating device to the wireless transmission chip. The wireless transmission chip transmits the second electric signal to an external device.

A remote control apparatus includes: a main controller, a wireless transmission chip, a gyroscope chip and an operating device; wherein the wireless transmission chip is electrically connected with the main controller; the gyroscope chip is electrically connected with the main controller; the operating device is electrically connected with the main controller. The gyroscope chip is used for detecting an inclination angle of the remote control apparatus relative to a horizontal plane, and sending a first electric signal representing a positioning status of the remote control apparatus to the main controller. The main controller is used for detecting an input level when the operating device is operated by an operator, and sending a second electric signal representing a movement direction instructed by the operating device to the wireless transmission chip. The wireless transmission chip transmits the second electric signal to an external device.

A remote control apparatus includes: a main controller, a wireless transmission chip, a gyroscope chip and an operating device; wherein the wireless transmission chip is electrically connected with the main controller; the gyroscope chip is electrically connected with the main controller; the operating device is electrically connected with the main controller. The gyroscope chip is used for detecting an inclination angle of the remote control apparatus relative to a horizontal plane, and sending a first electric signal representing a positioning status of the remote control apparatus to the main controller. The main controller is used for detecting an input level when the operating device is operated by an operator, and sending a second electric signal representing a movement direction instructed by the operating device to the wireless transmission chip. The wireless transmission chip transmits the second electric signal to an external device.

A cavity sensor including: a body defining a cavity, the cavity having an opening on one end and a closed surface on other end; a reflective surface disposed in the cavity, the reflective surface being angled 45 degrees relative to a propagation direction of an incoming wave through the opening; and first and second angle probes positioned on each of two ends of the reflective surface. Also provided is a cavity sensor including: a body defining a cavity, the body having two or more conduits, each having an opening, the body having a closed surface opposing the openings, and a probe positioned in the cavity at a position common to each of the two or more conduits.

A cavity sensor including: a body defining a cavity, the cavity having an opening on one end and a closed surface on other end; a reflective surface disposed in the cavity, the reflective surface being angled 45 degrees relative to a propagation direction of an incoming wave through the opening; and first and second angle probes positioned on each of two ends of the reflective surface. Also provided is a cavity sensor including: a body defining a cavity, the body having two or more conduits, each having an opening, the body having a closed surface opposing the openings, and a probe positioned in the cavity at a position common to each of the two or more conduits.

A vehicle leveling system has a sensor for sensing a reference state of a vehicle and a level state of the vehicle. The reference state is subtracted from the level state to determine a difference angle. The reference state is absolute flat or other reference angle. A smart device is in communication with the sensor to zero out the difference angle and level the vehicle. The smart devices provide feedback to a user to adjust orientation of the vehicle as to zero out the difference angle and level the vehicle. The feedback can be an audible or human sensory feedback, such as voice or tones. A plurality of jacks is used to level the vehicle by zeroing out the difference angle. The jacks can be controlled by the smart device or sensor. The sensor has a gyroscope providing multiple angles of orientation.

A vehicle leveling system has a sensor for sensing a reference state of a vehicle and a level state of the vehicle. The reference state is subtracted from the level state to determine a difference angle. The reference state is absolute flat or other reference angle. A smart device is in communication with the sensor to zero out the difference angle and level the vehicle. The smart devices provide feedback to a user to adjust orientation of the vehicle as to zero out the difference angle and level the vehicle. The feedback can be an audible or human sensory feedback, such as voice or tones. A plurality of jacks is used to level the vehicle by zeroing out the difference angle. The jacks can be controlled by the smart device or sensor. The sensor has a gyroscope providing multiple angles of orientation.