A dynamometer for nature's engines. - Andrew J. Taberner; Poul M. F. Nielsen; Callum M. Johnston; Alexander J. Anderson; Ming L. Cheuk; Amy S. Garrett; Jarrah Dowrick; Emily Lam Po Tang; Amir HajiRassouliha; Bryan P. Ruddy; Toan Pham; Kenneth Tran; et al. (IEEE Instrum. Meas. Mag., 2019)