Towards Developing an Aerial Mapping System for Stockpile Volume Estimation in Cement Plants

Integrated manufacturing systems such as cement processes are heavily dependent on stockpiles of different materials that serve as inputs to the different stages of production. Accurate estimation of material volume contained in these stockpiles is central to process profitability and waste elimination/minimisation. However, accurate estimation of stock within the cement industry is challenging owing to the unevenness of stock shapes and harsh environmental conditions (e.g. dust, temperature, humidity, etc.). This work provides a set of results obtained from preliminary investigation into the feasibility of deploying a low-cost aerial system to estimate stockpile volumes in open and semi-confined spaces within cement plants. An outdoor stockpile was first mapped using GPS for localisation, while 1D LiDAR and barometer were used for the stockpile height estimation. Visual inspection of the reconstructed stockpile surface showed strong correspondence to the actual stockpile. A second mission was conducted in a semi-confined space. The reconstructed surface appearance was inaccurate due to GPS-related issues; however, the volume was still estimated with reasonable accuracy, within 2.4% error. Future recommendations on upgrading the developed system to work within confined spaces are provided